Add parser tests

test/corpus/comment.txt

@@ -0,0 +1,101 @@
+=====================================
+empty
+=====================================
+
+#
+
+---
+
+(source
+  (comment))
+
+=====================================
+single line
+=====================================
+
+# single comment
+
+---
+
+(source
+  (comment))
+
+=====================================
+multiple start symbols
+=====================================
+
+### multiple "#"
+
+---
+
+(source
+  (comment))
+
+=====================================
+many consecutive lines
+=====================================
+
+# many
+# consecutive
+1
+# lines
+
+---
+
+(source
+  (comment)
+  (comment)
+  (integer)
+  (comment))
+
+=====================================
+in the same line as regular code
+=====================================
+
+1 # comment
+
+---
+
+(source
+  (integer)
+  (comment))
+
+=====================================
+matches inside a nested structure
+=====================================
+
+[ 1 ## inside a list
+, { 2 # and a tuple, too!
+  , 3 }
+]
+
+---
+
+(source
+  (list
+    (integer)
+    (comment)
+    (tuple
+      (integer)
+      (comment)
+      (integer))))
+
+=====================================
+does not match inside a string
+=====================================
+
+"# string"
+"this is #{interpolation}"
+
+---
+
+(source
+  (string
+    (string_start)
+    (string_content)
+    (string_end))
+  (string
+    (string_start)
+    (string_content)
+    (interpolation (identifier))
+    (string_end)))

test/corpus/do_end.txt

@@ -0,0 +1,580 @@
+=====================================
+call without arguments
+=====================================
+
+fun do
+  a
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier))))
+
+=====================================
+call with arguments in parentheses
+=====================================
+
+fun(a, b) do
+  c
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (identifier)
+      (identifier))
+    (do_block
+      (identifier))))
+
+=====================================
+call with arguments without parentheses
+=====================================
+
+fun a, b do
+  c
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (identifier)
+      (identifier))
+    (do_block
+      (identifier))))
+
+=====================================
+remote call
+=====================================
+
+Mod.fun do
+  a
+end
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (do_block
+      (identifier))))
+
+=====================================
+sticks to the outermost call
+=====================================
+
+outer_fun inner_fun arg do
+  a
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)
+        (arguments
+          (identifier)))
+    (do_block
+      (identifier))))
+
+=====================================
+newline before do
+=====================================
+
+fun x
+do
+  x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (identifier))
+    (do_block
+      (identifier))))
+
+=====================================
+stab clause / no arguments
+=====================================
+
+fun do
+ () -> x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments)
+        (body
+          (identifier))))))
+
+=====================================
+stab clause / no arguments without parentheses
+=====================================
+
+fun do
+  -> x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (body
+          (identifier))))))
+
+=====================================
+stab clause / one argument
+=====================================
+
+fun do
+  x -> x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments
+          (identifier))
+        (body
+          (identifier))))))
+
+=====================================
+stab clause / many arguments
+=====================================
+
+fun do
+  x, y, 1 -> :ok
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments
+          (identifier)
+          (identifier)
+          (integer))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+stab clause / arguments in parentheses
+=====================================
+
+fun do
+  (x, y) -> :ok
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments
+          (identifier)
+          (identifier))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+stab clause / many clauses
+=====================================
+
+fun do
+  1 -> :yes
+  2 -> :no
+  other -> :maybe
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments
+          (integer))
+        (body
+          (atom
+            (atom_literal))))
+      (stab_clause
+        (arguments
+          (integer))
+        (body
+          (atom
+            (atom_literal))))
+      (stab_clause
+        (arguments
+          (identifier))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+stab clause / multiline expression
+=====================================
+
+fun do
+  x ->
+    y
+    x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments
+          (integer))
+        (body
+          (identifier)
+          (identifier))))))
+
+=====================================
+stab clause / with guard / no arguments
+=====================================
+
+fun do
+  () when node() == :nonode@nohost -> true
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (binary_operator
+          (arguments)
+          (binary_operator
+            (call
+              (identifier)
+              (arguments))
+            (atom
+              (atom_literal))))
+        (body
+          (boolean))))))
+
+=====================================
+stab clause / with guard / one argument
+=====================================
+
+fun do
+  x when x == [] -> x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (binary_operator
+          (arguments
+            (identifier))
+          (binary_operator
+            (identifier)
+            (list)))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+stab clause / with guard / multiple arguments
+=====================================
+
+fun do
+  x, y when x == [] -> x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (binary_operator
+          (arguments
+            (identifier)
+            (identifier))
+          (binary_operator
+            (identifier)
+            (list)))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+stab clause / with guard / arguments in parentheses
+=====================================
+
+fun do
+  (x, y) when y == [] -> y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (binary_operator
+          (arguments
+            (identifier)
+            (identifier))
+          (binary_operator
+            (identifier)
+            (list)))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+stab clause / with guard / multiple guards
+=====================================
+
+fun do
+  x when x > 10 when x < 5 -> x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (binary_operator
+          (arguments
+            (identifier))
+          (binary_operator
+            (binary_operator
+              (identifier)
+              (identifier))
+            (binary_operator
+              (identifier)
+              (identifier))))
+        (body
+          (atom
+            (atom_literal)))))))
+
+
+=====================================
+pattern matching
+=====================================
+
+fun do
+  [h | tail] -> {h, tail}
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (stab_clause
+        (arguments
+          (list
+            (binary_operator
+              (identifier)
+              (identifier))))
+        (body
+          (atom
+            (atom_literal)))))))
+
+=====================================
+child blocks / after
+=====================================
+
+fun do
+  x
+after
+  y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (after_block
+        (identifier)))))
+
+=====================================
+child blocks / catch
+=====================================
+
+fun do
+  x
+catch
+  y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (catch_block
+        (identifier)))))
+
+=====================================
+child blocks / else
+=====================================
+
+fun do
+  x
+else
+  y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (else_block
+        (identifier)))))
+
+=====================================
+child blocks / rescue
+=====================================
+
+fun do
+  x
+rescue
+  y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (rescue_block
+        (identifier)))))
+
+=====================================
+child blocks / duplicated
+=====================================
+
+fun do
+  x
+after
+  y
+after
+  z
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (after_block
+        (identifier))
+      (after_block
+        (identifier)))))
+
+=====================================
+child blocks / mixed
+=====================================
+
+fun do
+  x
+else
+  y
+after
+  z
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (else_block
+        (identifier))
+      (after_block
+        (identifier)))))
+
+=====================================
+child blocks / stab clause
+=====================================
+
+fun do
+  x
+rescue
+  y -> y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (do_block
+      (identifier)
+      (rescue_block
+        (stab_clause
+          (arguments
+            (identifier))
+          (body
+            (identifier)))))))

test/corpus/edge_syntax.txt

@@ -0,0 +1,69 @@
+=====================================
+operator with arity (valid and supported by IEx.Helpers.h)
+=====================================
+
+::/2
+@ / 1
+& / 1
+
+---
+
+(source
+  (binary_operator
+    (operator_identifier)
+    (integer)))
+
+=====================================
+map with identifiers
+=====================================
+
+%{a}
+%{a, b}
+
+---
+
+(source
+  (map
+    (map_content
+      (identifier)))
+  (map
+    (map_content
+      (identifier)
+      (identifier))))
+
+=====================================
+def with remote call
+=====================================
+
+def Mod.fun(x), do: 1
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (dot
+          (alias)
+          (identifier))
+        (arguments
+          (identifier)))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+[error] arrow outside of map
+=====================================
+
+a => b
+
+---
+
+(source
+  (identifier)
+  (ERROR
+    (identifier)))

test/corpus/expression/anonymous_function.txt

@@ -0,0 +1,323 @@
+=====================================
+no arguments
+=====================================
+
+fn() -> 1 end
+fn () -> 1 end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments)
+      (body
+        (integer))))
+  (anonymous_function
+    (stab_clause
+      (body
+        (integer)))))
+
+=====================================
+no arguments without parentheses
+=====================================
+
+fn -> 1 end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (body
+        (integer)))))
+
+=====================================
+one argument
+=====================================
+
+fn(x) -> x end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (identifier))
+      (body
+        (identifier)))))
+
+=====================================
+one argument without parentheses
+=====================================
+
+fn x -> x end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (identifier))
+      (body
+        (identifier)))))
+
+=====================================
+many arguments
+=====================================
+
+fn(x, y) -> x + y end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (identifier)
+        (identifier))
+      (body
+        (binary_operator
+          (identifier)
+          (identifier))))))
+
+=====================================
+many arguments without parentheses
+=====================================
+
+fn x, y -> x + y end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (identifier)
+        (identifier))
+      (body
+        (binary_operator
+          (identifier)
+          (identifier))))))
+
+=====================================
+multiline body
+=====================================
+
+fn x, y ->
+  y
+  x
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (identifier)
+        (identifier))
+      (body
+        (identifier)
+        (identifier)))))
+
+=====================================
+many clauses
+=====================================
+
+fn
+  1 -> :yes
+  2 -> :no
+  other -> :maybe
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (integer))
+      (body
+        (atom
+          (atom_literal))))
+    (stab_clause
+      (arguments
+        (integer))
+      (body
+        (atom
+          (atom_literal))))
+    (stab_clause
+      (arguments
+        (identifier))
+      (body
+        (atom
+          (atom_literal))))))
+
+=====================================
+with guard / no arguments
+=====================================
+
+fn
+  () when node() == :nonode@nohost -> true
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (binary_operator
+        (arguments)
+        (binary_operator
+          (call
+            (identifier)
+            (arguments))
+          (atom
+            (atom_literal))))
+      (body
+        (atom
+          (atom_literal))))))
+
+=====================================
+with guard / one argument
+=====================================
+
+fn
+  x when x == [] -> x
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (binary_operator
+        (arguments
+          (identifier))
+        (binary_operator
+          (identifier)
+          (list)))
+      (body
+        (atom
+          (atom_literal))))))
+
+=====================================
+with guard / multiple arguments
+=====================================
+
+fn
+  x, y when x == [] -> x
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (binary_operator
+        (arguments
+          (identifier)
+          (identifier))
+        (binary_operator
+          (identifier)
+          (list)))
+      (body
+        (atom
+          (atom_literal))))))
+
+=====================================
+with guard / arguments in parentheses
+=====================================
+
+fn
+  (x, y) when y == [] -> y
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (binary_operator
+        (arguments
+          (identifier)
+          (identifier))
+        (binary_operator
+          (identifier)
+          (list)))
+      (body
+        (atom
+          (atom_literal))))))
+
+=====================================
+with guard / multiple guards
+=====================================
+
+fn
+  x when x > 10 when x < 5 -> x
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (binary_operator
+        (arguments
+          (identifier))
+        (binary_operator
+          (binary_operator
+            (identifier)
+            (identifier))
+          (binary_operator
+            (identifier)
+            (identifier))))
+      (body
+        (atom
+          (atom_literal))))))
+
+=====================================
+pattern matching
+=====================================
+
+fn
+  [h | tail] -> {h, tail}
+  %{x: x} when x == 1 -> 1
+end
+
+---
+
+(source
+  (anonymous_function
+    (stab_clause
+      (arguments
+        (list
+          (binary_operator
+            (identifier)
+            (identifier))))
+      (body
+        (atom
+          (atom_literal))))
+    (stab_clause
+      (binary_operator
+        (arguments
+          (map
+            (map_content
+              (keywords
+                (pair
+                  (keyword
+                    (atom_literal))
+                  (identifier))))))
+        (binary_operator
+          (binary_operator
+            (identifier)
+            (identifier))
+          (binary_operator
+            (identifier)
+            (identifier))))
+      (body
+        (atom
+          (atom_literal))))))

test/corpus/expression/block.txt

@@ -0,0 +1,96 @@
+=====================================
+empty
+=====================================
+
+()
+
+---
+
+(source
+  (block))
+
+=====================================
+single expression
+=====================================
+
+(1)
+
+---
+
+(source
+  (block
+    (integer)))
+
+=====================================
+multiple expressions separated by newline
+=====================================
+
+(
+  1
+  2
+)
+
+---
+
+(source
+  (block
+    (integer)
+    (integer)))
+
+=====================================
+multiple expressions separated by semicolon
+=====================================
+
+(1;2)
+
+---
+
+(source
+  (block
+    (integer)
+    (integer)))
+
+=====================================
+multiple expressions separated by mixed separators
+=====================================
+
+(
+  1
+
+  ;
+
+  2
+)
+
+---
+
+(source
+  (block
+    (integer)
+    (integer)))
+
+=====================================
+leading semicolon
+=====================================
+
+(;1;2)
+
+---
+
+(source
+  (block
+    (integer)
+    (integer)))
+
+=====================================
+trailing semicolon
+=====================================
+
+(1;2;)
+
+---
+
+(source
+  (block
+    (integer)
+    (integer)))

test/corpus/expression/call.txt

@@ -0,0 +1,806 @@
+=====================================
+local call / no arguments
+=====================================
+
+fun()
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments)))
+
+=====================================
+local call / arguments in parentheses
+=====================================
+
+fun(a)
+fun([1, 2], option: true, other: 5)
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (identifier)))
+  (call
+    (identifier)
+    (arguments
+      (list
+        (integer)
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (boolean))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+local call / arguments without parentheses
+=====================================
+
+fun a
+fun [1, 2], option: true, other: 5
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (identifier)))
+  (call
+    (identifier)
+    (arguments
+      (list
+        (integer)
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (boolean))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+local call / nested with parentheses
+=====================================
+
+outer_fun(inner_fun(a))
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)
+        (arguments
+          (identifier))))))
+
+=====================================
+local call / nested without parentheses (right associativity)
+=====================================
+
+outer_fun inner_fun a
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)
+        (arguments
+          (identifier))))))
+
+=====================================
+local call / precedence with operator
+=====================================
+
+fun +1
+outer_fun 1 + 1
+1 + inner_fun 1
+outer_fun 1 + inner_fun 1
+fun 1, 2 |> other_fun
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (unary_operator
+        (integer))))
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (integer)
+        (integer))))
+  (binary_operator
+    (integer)
+    (call
+      (identifier)
+        (arguments
+          (integer))))
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (integer)
+        (call
+          (identifier)
+          (arguments
+            (integer))))))
+  (call
+    (identifier)
+    (arguments
+      (integer)
+      (binary_operator
+        (integer)
+        (identifier)))))
+
+=====================================
+local call / treats nonimmediate parentheses as a block argument
+=====================================
+
+fun (x)
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (block
+        (identifier)))))
+
+=====================================
+remote call / no arguments
+=====================================
+
+Mod.fun()
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments)))
+
+=====================================
+remote call / no arguments without parentheses
+=====================================
+
+Mod.fun
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))))
+
+=====================================
+remote call / arguments in parentheses
+=====================================
+
+Mod.fun(a)
+Mod.fun([1, 2], option: true, other: 5)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (identifier)))
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (list
+        (integer)
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (boolean))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+remote call / arguments without parentheses
+=====================================
+
+Mod.fun a
+Mod.fun [1, 2], option: true, other: 5
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (identifier)))
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (list
+        (integer)
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (boolean))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+remote call / nested with parentheses
+=====================================
+
+Mod.outer_fun(Mod.inner_fun(a))
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (call
+        (dot
+          (alias)
+          (identifier))
+        (arguments
+          (identifier))))))
+
+=====================================
+remote call / nested without parentheses (right associativity)
+=====================================
+
+Mod.outer_fun Mod.inner_fun a
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (call
+        (dot
+          (alias)
+          (identifier))
+        (arguments
+          (identifier))))))
+
+=====================================
+remote call / precedence with operator
+=====================================
+
+Mod.outer_fun 1 + 1
+1 + Mod.inner_fun 1
+Mod.outer_fun 1 + Mod.inner_fun 1
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (binary_operator
+        (integer)
+        (integer))))
+  (binary_operator
+    (integer)
+    (call
+      (dot
+        (alias)
+        (identifier))
+        (arguments
+          (integer))))
+    (call
+      (dot
+        (alias)
+        (identifier))
+    (arguments
+      (binary_operator
+        (integer)
+        (call
+          (dot
+            (alias)
+            (identifier))
+          (arguments
+            (integer)))))))
+
+=====================================
+remote call / treats nonimmediate parentheses as a block argument
+=====================================
+
+Mod.fun (x)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (block
+        (identifier)))))
+
+=====================================
+remote call / multi-level alias
+=====================================
+
+Mod1.Mod2.Mod3.fun(a)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+remote call / operator
+=====================================
+
+Kernel.+(a, b)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (operator_identifier))
+    (arguments
+      (identifier)
+      (identifier))))
+
+=====================================
+remote call / quoted function name
+=====================================
+
+Mod."fun"(a)
+Mod.'fun'(a)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+remote call / atom literal module
+=====================================
+
+:mod.fun(a)
+:"Elixir.Mod".fun(a)
+
+---
+
+(source
+  (call
+    (dot
+      (atom
+        (atom_literal))
+      (identifier))
+    (arguments
+      (identifier)))
+  (call
+    (dot
+      (atom
+        (string_content))
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+anonymous call / no arguments
+=====================================
+
+fun.()
+
+---
+
+(source
+  (call
+    (dot
+      (identifier))
+    (arguments)))
+
+=====================================
+anonymous call / arguments in parentheses
+=====================================
+
+fun.(a)
+fun.([1, 2], option: true, other: 5)
+
+---
+
+(source
+  (call
+    (dot
+      (identifier))
+    (arguments
+      (identifier)))
+  (call
+    (dot
+      (identifier))
+    (arguments
+      (list
+        (integer)
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (boolean))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+anonymous call / nested with parentheses
+=====================================
+
+outer_fun.(inner_fun.(a))
+
+---
+
+(source
+  (call
+    (dot
+      (identifier))
+    (arguments
+      (call
+        (dot
+          (identifier))
+        (arguments
+          (identifier))))))
+
+=====================================
+mixed call types
+=====================================
+
+Mod.outer_fun mid_fun inner_fun.(a)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (call
+        (identifier)
+        (call
+          (dot
+            (identifier))
+          (arguments
+            (identifier)))))))
+
+=====================================
+identifier call
+=====================================
+
+mod.fun(a)
+
+---
+
+(source
+  (call
+    (dot
+      (identifier)
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+nested identifier call
+=====================================
+
+map.mod.fun(a)
+
+---
+
+(source
+  (call
+    (dot
+      (call
+        (dot
+          (identifier)
+          (identifier)))
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+reserved word call
+=====================================
+
+a.and
+
+---
+
+(source
+  (call
+    (dot
+      (identifier)
+      (identifier))))
+
+=====================================
+range call
+=====================================
+
+(1..2).step
+(1..2//3).step
+
+---
+
+(source
+  (call
+    (dot
+      (block
+        (binary_operator
+          (integer)
+          (integer)))
+      (identifier)))
+  (call
+    (dot
+      (block
+        (binary_operator
+          (binary_operator
+            (integer)
+            (integer))
+          (integer))))
+    (identifier)))
+
+=====================================
+multi-expression block call
+=====================================
+
+(
+  x
+  1..2
+).step
+
+---
+
+(source
+  (call
+    (dot
+      (block
+        (identifier)
+        (binary_operator
+          (integer)
+          (integer)))
+      (identifier))))
+
+=====================================
+map call
+=====================================
+
+%{}.field
+
+---
+
+(source
+  (call
+    (dot
+      (map)
+      (identifier))))
+
+=====================================
+struct call
+=====================================
+
+%Mod{}.field
+
+---
+
+(source
+  (call
+    (dot
+      (map
+        (struct
+          (alias)))
+      (identifier))))
+
+=====================================
+arbitrary term call
+=====================================
+
+1.(1, 2)
+
+---
+
+(source
+  (call
+    (dot
+      (integer))
+    (arguments
+      (integer)
+      (integer))))
+
+=====================================
+escaped newline call
+=====================================
+
+fun \
+a
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (identifier))))
+
+=====================================
+keyword list trailing separator
+=====================================
+
+fun(option: true, other: 5,)
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (boolean))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+newline before dot
+=====================================
+
+Mod
+  .fun(a)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+newline after dot
+=====================================
+
+Mod.
+  fun(a)
+
+---
+
+(source
+  (call
+    (dot
+      (alias)
+      (identifier))
+    (arguments
+      (identifier))))
+
+=====================================
+access syntax
+=====================================
+
+map[key]
+map[:key]
+
+---
+
+(source
+  (access_call
+    (identifier)
+    (identifier))
+  (access_call
+    (identifier)
+    (atom
+      (atom_literal))))
+
+=====================================
+access syntax / does not allow whitespace
+=====================================
+
+map [key]
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (list
+        (identifier)))))
+
+=====================================
+access syntax / precedence over dot call
+=====================================
+
+map[:mod].fun
+
+---
+
+(source
+  (call
+    (dot
+      (access_call
+        (identifier)
+        (atom
+          (atom_literal)))
+      (identifier))))
+
+=====================================
+[error] leading argument separator
+=====================================
+
+fun(, a)
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (ERROR)
+      (identifier))))

test/corpus/expression/capture.txt

@@ -0,0 +1,130 @@
+=====================================
+anonymous function
+=====================================
+
+& &1 + &2
+&(&1 + &2)
+&foo(&1, a, &2)
+
+---
+
+(source
+  (unary_operator
+    (binary_operator
+      (unary_operator
+        (integer))
+      (unary_operator
+        (integer))))
+  (unary_operator
+    (binary_operator
+      (unary_operator
+        (integer))
+      (unary_operator
+        (integer))))
+  (unary_operator
+    (call
+      (arguments
+        (unary_operator
+          (integer))
+        (identifier)
+        (unary_operator
+          (integer))))))
+
+=====================================
+argument call
+=====================================
+
+& &1.some_fun
+&(&1.some_fun)
+& &1.(&2)
+
+---
+
+(source
+  (unary_operator
+    (call
+      (dot
+        (unary_operator
+          (integer)
+        (identifier)))))
+  (unary_operator
+    (call
+      (dot
+        (unary_operator
+          (integer)
+        (identifier)))))
+  (unary_operator
+    (call
+      (dot
+        (unary_operator
+          (integer)
+        (arguments
+          (unary_operator
+            (integer))))))))
+
+=====================================
+remote MFA
+=====================================
+
+&Mod.fun/1
+
+---
+
+(source
+  (unary_operator
+    (binary_operator
+      (call
+        (dot
+          (alias)
+          (identifier)))
+      (integer))))
+
+=====================================
+remote operator MFA
+=====================================
+
+&Kernel.>=/2
+
+---
+
+(source
+  (unary_operator
+    (binary_operator
+      (call
+        (dot
+          (alias)
+          (operator_identifier)))
+      (integer))))
+
+=====================================
+local MFA
+=====================================
+
+&fun/1
+
+---
+
+(source
+  (unary_operator
+    (binary_operator
+      (identifier)
+      (integer))))
+
+=====================================
+local operator MFA
+=====================================
+
+&>=/2
+&//2
+
+---
+
+(source
+  (unary_operator
+    (binary_operator
+      (operator_identifier)
+      (integer)))
+  (unary_operator
+    (binary_operator
+      (operator_identifier)
+      (integer))))

test/corpus/expression/operator.txt

@@ -0,0 +1,356 @@
+=====================================
+unary
+=====================================
+
+@arg
+
++arg
+-arg
+!arg
+^arg
+not arg
+~~~arg
+
+&arg
+
+---
+
+(source
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier))
+  (unary_operator
+    (identifier)))
+
+=====================================
+binary left associative
+=====================================
+
+a * b * c
+a / b / c
+
+a + b + c
+a - b - c
+
+a ^^^ b ^^^ c
+
+a in b in c
+a not in b not in c
+
+a |> b |> c
+a <<< b <<< c
+a >>> b >>> c
+a <<~ b <<~ c
+a ~>> b ~>> c
+a <~ b <~ c
+a ~> b ~> c
+a <~> b <~> c
+a <|> b <|> c
+
+a < b < c
+a > b > c
+a <= b <= c
+a >= b >= c
+
+a == b == c
+a != b != c
+a =~ b =~ c
+a === b === c
+a !== b !== c
+
+a && b && c
+a &&& b &&& c
+a and b and c
+
+a || b || c
+a ||| b ||| c
+a or b or c
+
+a <- b <- c
+a \\ b \\ c
+
+---
+
+(source
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier)))
+
+=====================================
+binary right associative
+=====================================
+
+a ++ b ++ c
+a -- b -- c
+a +++ b +++ c
+a --- b --- c
+a .. b .. c
+a <> b <> c
+
+a = b = c
+
+a | b | c
+
+a :: b :: c
+
+a when b when c
+
+---
+
+(source
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier)))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier))))
+
+=====================================
+precedence on the same level falls back to associativity
+=====================================
+
+a * b / c
+a + b - c
+a in b not in c
+a <<< b >>> c
+a < b > c
+a == b != c
+a &&& b && c
+a ||| b || c
+a <- b \\ c
+
+a ++ b -- c
+
+---
+
+(source
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (binary_operator (identifier) (identifier)) (identifier))
+  (binary_operator (identifier) (binary_operator (identifier) (identifier))))
+
+=====================================
+precedence on different levels
+=====================================
+
+& @ a - b
+a -- b + c
+a - b ++ c
+a = b <<< c
+
+a + b * c - d
+
+---
+
+(source
+  (unary_operator
+    (binary_operator
+      (unary_operator
+        (identifier))
+      (identifier)))
+  (binary_operator
+    (identifier)
+    (binary_operator
+      (identifier)
+      (identifier)))
+  (binary_operator
+    (binary_operator
+      (identifier)
+      (identifier))
+    (identifier))
+  (binary_operator
+    (identifier)
+    (binary_operator
+      (identifier)
+      (identifier)))
+  (binary_operator
+    (binary_operator
+      (identifier)
+      (binary_operator
+        (identifier)
+        (identifier)))
+    (identifier)))
+
+=====================================
+precedence determined by parentheses
+=====================================
+
+(& a) - b
+
+(a + b) * (c - d)
+
+---
+
+(source
+  (binary_operator
+    (unary_operator
+      (identifier))
+    (identifier))
+  (binary_operator
+    (block
+      (binary_operator
+        (identifier)
+        (identifier)))
+    (block
+      (binary_operator
+        (identifier)
+        (identifier)))))
+
+=====================================
+multiline
+=====================================
+
+-
+x
+
+x
+not in
+[y]
+
+---
+
+(source
+  (unary_operator
+    (identifier))
+  (binary_operator
+    (identifier)
+    (list
+      (identifier))))
+
+=====================================
+stepped range
+=====================================
+
+1 .. 2 // 3
+1..2//3
+0..1//-1
+
+---
+
+(source
+  (binary_operator
+    (binary_operator
+      (integer)
+      (integer))
+    (integer))
+  (binary_operator
+    (binary_operator
+      (integer)
+      (integer))
+    (integer))
+  (binary_operator
+    (binary_operator
+      (integer)
+      (integer))
+    (unary_operator
+      (integer))))
+
+=====================================
+stepped range / multiline
+=====================================
+
+1..2
+// 4
+
+---
+
+(source
+  (binary_operator
+    (binary_operator
+      (integer)
+      (integer))
+    (integer)))
+
+=====================================
+stepped ranges / blocks
+=====================================
+
+foo do end..bar do end//baz do end
+1..(2//3)
+(1..2)//3
+(1..2)//(3)
+
+---
+
+(source
+  (binary_operator
+    (binary_operator
+      (call
+        (identifier)
+        (do_block))
+      (call
+        (identifier)
+        (do_block)))
+    (call
+      (identifier)
+      (do_block)))
+  (binary_operator
+    (integer)
+    (block
+      (binary_operator
+        (integer)
+        (integer))))
+  (binary_operator
+    (block
+      (binary_operator
+        (integer)
+        (integer)))
+    (integer))
+  (binary_operator
+    (block
+      (binary_operator
+        (integer)
+        (integer)))
+    (block
+      (integer))))

test/corpus/expression/sigil.txt

@@ -0,0 +1,246 @@
+=====================================
+simple literal
+=====================================
+
+~s(content)
+~r{content}
+~w[content]
+~a<content>
+~b"content"
+~c'content'
+~d|content|
+~e/content/
+
+---
+
+(source
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content))
+  (sigil (sigil_name) (string_content)))
+
+
+=====================================
+multiple lines
+=====================================
+
+~s"line 1
+line 2"
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)))
+
+=====================================
+interpolation
+=====================================
+
+~s"hey #{name}!"
+~r/hey #{
+  name
+}!/
+~w{##{name}#}
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (sigil
+    (sigil_name)
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (sigil
+    (sigil_name)
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content)))
+
+=====================================
+nested interpolation
+=====================================
+
+~s{this is #{~s{number #{1}}}!}
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)
+    (interpolation
+      (sigil
+        (sigil_name)
+        (string_content)
+        (interpolation
+          (identifier))))
+    (string_content)))
+
+=====================================
+escape sequence
+=====================================
+
+~s{_\}_\n_\t_\r_\e_\\_\1_\x3f_\u0065\u0301_}
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+escaped interpolation
+=====================================
+
+~s{\#{1}}
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+upper sigil / no interpolation
+=====================================
+
+~S"hey #{name}!"
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)))
+
+=====================================
+upper sigil / no escape sequence
+=====================================
+
+~S"\n"
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)))
+
+=====================================
+upper sigil / escape terminator
+=====================================
+
+~S"content \" content"
+~S{content \} content}
+~S/content \/ content/
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)
+    (escape_sequence)
+    (string_content))
+  (sigil
+    (sigil_name)
+    (string_content)
+    (escape_sequence)
+    (string_content))
+  (sigil
+    (sigil_name)
+    (string_content)
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+heredoc delimiter
+=====================================
+
+~s"""
+text
+with "quotes"
+"""
+
+~s'''
+text
+with 'quotes'
+'''
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content))
+  (sigil
+    (sigil_name)
+    (string_content)))
+
+=====================================
+modifiers
+=====================================
+
+~r/left|right/i
+~r/left|right/iUx
+
+---
+
+(source
+  (sigil
+    (sigil_name)
+    (string_content)
+    (sigil_modifiers))
+  (sigil
+    (sigil_name)
+    (sigil_modifiers)))
+
+=====================================
+[error] accepts only a single character
+=====================================
+
+~mysigil"content"
+
+---
+
+(source
+  (ERROR)
+  (call
+    (string
+      (string_content))))

test/corpus/integration/function_definition.txt

@@ -0,0 +1,364 @@
+=====================================
+def / no arguments
+=====================================
+
+def fun() do
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)
+        (arguments)))
+    (do_block)))
+
+=====================================
+def / no arguments without parentheses
+=====================================
+
+def fun do
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)))
+    (do_block)))
+
+=====================================
+def / one argument
+=====================================
+
+def fun(x) do
+  x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)))))
+    (do_block
+      (identifier))))
+
+=====================================
+def / one argument without parentheses
+=====================================
+
+def fun x do
+  x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)))))
+    (do_block
+      (identifier))))
+
+=====================================
+def / many arguments
+=====================================
+
+def fun(x, y) do
+  x + y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)
+            (identifier)))))
+    (do_block
+      (binary_operator
+        (identifier)
+        (identifier)))))
+
+=====================================
+def / many arguments without parentheses
+=====================================
+
+def fun x, y do
+  x + y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)
+            (identifier)))))
+    (do_block
+      (binary_operator
+        (identifier)
+        (identifier)))))
+
+=====================================
+def / default arguments
+=====================================
+
+def fun x, y \\ 1 do
+  x + y
+end
+
+def fun(x, y \\ 1) do
+  x + y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)
+            (binary_operator
+              (identifier)
+              (integer))))))
+    (do_block
+      (binary_operator
+        (identifier)
+        (identifier))))
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)
+            (binary_operator
+              (identifier)
+              (integer))))))
+    (do_block
+      (binary_operator
+        (identifier)
+        (identifier)))))
+
+=====================================
+def / keyword do block
+=====================================
+
+def fun(), do: 1
+def fun(x), do: x
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)))
+    (keywords
+      (pair
+        (keyword
+          (atom_literal))
+        (integer))))
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)))))
+    (keywords
+      (pair
+        (keyword
+          (atom_literal))
+        (identifier)))))
+
+=====================================
+def / pattern matching
+=====================================
+
+def fun([{x, y} | tail]) do
+  x + y
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier)
+        (arguments
+          (list
+            (binary_operator
+              (tuple
+                (identifier)
+                (identifier))
+              (identifier))))))
+    (do_block
+      (binary_operator
+        (identifier)
+        (identifier)))))
+
+=====================================
+def / with guard
+=====================================
+
+def fun(x) when x == 1 do
+  x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (call
+          (identifier
+            (arguments
+              (identifier))))
+        (binary_operator
+          (identifier)
+          (integer))))
+    (do_block
+      (identifier))))
+
+=====================================
+def / with guard / multiple guards
+=====================================
+
+def fun(x) when x > 10 when x < 5 do
+  x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (call
+          (identifier
+            (arguments
+              (identifier))))
+        (binary_operator
+          (binary_operator
+            (identifier)
+            (integer))
+          (binary_operator
+            (identifier)
+            (integer)))))
+    (do_block
+      (identifier))))
+
+=====================================
+defp
+=====================================
+
+defp fun(x) do
+  x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)))))
+    (do_block
+      (identifier))))
+
+=====================================
+defmacro
+=====================================
+
+defmacro fun(x) do
+  quote do
+    [unquote(x)]
+  end
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (call
+        (identifier
+          (arguments
+            (identifier)))))
+    (do_block
+      (call
+        (identifier)
+        (do_block
+          (list
+            (call
+              (identifier)
+              (arguments
+                (identifier)))))))))
+
+=====================================
+defguard
+=====================================
+
+defguard is_even(term) when is_integer(term) and rem(term, 2) == 0
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (call
+          (identifier
+            (arguments
+              (identifier))))
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (identifier)))
+          (binary_operator
+            (call
+              (identifier)
+              (arguments
+                (identifier)
+                (integer)))
+            (integer)))))))

test/corpus/integration/kernel.txt

@@ -0,0 +1,136 @@
+=====================================
+for / enumerable
+=====================================
+
+for n <- [1, 2], do: n * 2
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (identifier)
+        (list
+          (integer)
+          (integer))))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (binary_operator
+            (identifier)
+            (integer))))))
+
+=====================================
+for / enumerable / with options and block
+=====================================
+
+for line <- IO.stream(), into: IO.stream() do
+  String.upcase(line)
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (identifier)
+        (call
+          (dot
+            (alias)
+            (identifier))))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (call
+            (dot
+              (alias)
+              (identifier))))))
+    (do_block
+      (call
+        (dot
+          (alias)
+          (identifier))
+        (arguments
+          (identifier))))))
+
+=====================================
+for / binary
+=====================================
+
+for <<c <- " hello world ">>, c != ?\s, into: "", do: <<c>>
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary
+        (binary_operator
+          (identifier)
+          (string
+            (string_content))))
+      (binary_operator
+        (identifier)
+        (char))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (string
+            (string_content)))
+        (pair
+          (keyword
+            (atom_literal))
+          (binary
+            (identifier)))))))
+
+=====================================
+for / reduce
+=====================================
+
+for x <- [1, 2, 1], reduce: %{} do
+  acc -> Map.update(acc, x, 1, & &1 + 1)
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (binary_operator
+        (identifier)
+        (list
+          (integer)
+          (integer)
+          (integer)))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (map))))
+    (do_block
+      (stab_clause
+        (arguments
+          (identifier))
+        (body
+          (call
+            (dot
+              (alias)
+              (identifier))
+            (arguments
+              (identifier)
+              (identifier)
+              (integer)
+              (unary_operator
+                (binary_operator
+                  (unary_operator
+                    (integer))
+                  (integer))))))))))

test/corpus/integration/module_definition.txt

@@ -0,0 +1,140 @@
+=====================================
+empty module definition
+=====================================
+
+defmodule Mod do
+end
+
+defmodule Mod.Child do
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (alias))
+    (do_block))
+  (call
+    (identifier)
+    (arguments
+      (alias))
+    (do_block)))
+
+=====================================
+module definition with atom literal
+=====================================
+
+defmodule :mod do
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (atom
+        (atom_literal)))
+    (do_block)))
+
+=====================================
+full module definition
+=====================================
+
+defmodule Mod do
+  @moduledoc """
+  Example module
+  """
+
+  use UseMod
+
+  @attribute 1
+
+  @doc """
+  Example function
+  """
+  @spec func(integer) :: integer
+  def func(x) when is_integer(x) do
+    priv(x) + priv(x)
+  end
+
+  defp priv(x), do: x * x
+end
+
+---
+
+(source
+  (call
+    (identifier)
+    (arguments
+      (alias))
+    (do_block
+      (unary_operator
+        (call
+          (identifier)
+          (arguments
+            (string
+              (string_content)))))
+      (call
+        (identifier)
+        (arguments
+          (alias)))
+      (unary_operator
+        (call
+          (identifier)
+          (arguments
+            (integer))))
+      (unary_operator
+        (call
+          (identifier)
+          (arguments
+            (string
+              (string_content)))))
+      (unary_operator
+        (call
+          (identifier)
+          (arguments
+            (binary_operator
+              (call
+                (identifier)
+                (arguments
+                  (identifier)))
+              (identifier)))))
+      (call
+        (identifier)
+        (arguments
+          (binary_operator
+            (call
+              (identifier)
+              (arguments
+                (identifier)))
+            (call
+              (identifier)
+              (arguments
+                (identifier)))))
+        (do_block
+          (binary_operator
+            (call
+              (identifier)
+              (arguments
+                (identifier)))
+            (call
+              (identifier)
+              (arguments
+                (identifier))))))
+      (call
+        (identifier)
+        (arguments
+          (call
+            (identifier)
+            (arguments
+              (identifier)))
+          (keywords
+            (pair
+              (keyword
+                (atom_literal))
+              (binary_operator
+                (identifier)
+                (identifier)))))))))

test/corpus/integration/spec.txt

@@ -0,0 +1,242 @@
+=====================================
+without type parentheses
+=====================================
+
+@spec fun(atom, integer, keyword) :: string
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (identifier)
+              (identifier)
+              (identifier)))
+          (identifier))))))
+
+=====================================
+with type parentheses
+=====================================
+
+@spec fun(atom(), integer(), keyword()) :: string()
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (call
+                (identifier))
+              (call
+                (identifier))
+              (call
+                (identifier))))
+          (call
+            (identifier)))))))
+
+=====================================
+with literals
+=====================================
+
+@spec fun(%{key: atom}) :: {:ok, atom} | {:error, binary}
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (map
+                (map_content
+                  (keywords
+                    (pair
+                      (keyword
+                        (atom_literal)
+                      (identifier))))))))
+          (binary_operator
+            (tuple
+              (atom
+                (atom_literal))
+              (identifier))
+            (tuple
+              (atom
+                (atom_literal))
+              (identifier))))))))
+
+=====================================
+with function reference
+=====================================
+
+@spec fun((-> atom), (atom -> integer)) :: integer
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (stab_clause
+                (body
+                  (identifier)))
+              (stab_clause
+                (arguments
+                  (identifier))
+                (body
+                  (identifier)))))
+          (identifier))))))
+
+=====================================
+with remote type
+=====================================
+
+@spec fun(Keyword.t()) :: String.t()
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (call
+                (dot
+                  (alias)
+                  (identifier)))))
+          (call
+            (dot
+              (alias)
+              (identifier))))))))
+
+=====================================
+with type guard
+=====================================
+
+@spec fun(arg1, arg2) :: {arg1, arg2} when arg1: atom, arg2: integer
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (binary_operator
+            (call
+              (identifier)
+              (arguments
+                (identifier)
+                (identifier)))
+            (tuple
+              (identifier)
+              (identifier)))
+          (keywords
+            (pair
+              (keyword
+                (atom_literal))
+              (identifier))
+            (pair
+              (keyword
+                (atom_literal))
+              (identifier))))))))
+
+=====================================
+with named arguments
+=====================================
+
+@spec days_since_epoch(year :: integer, month :: integer, day :: integer) :: integer
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (call
+            (identifier)
+            (arguments
+              (binary_operator
+                (identifier)
+                (identifier))
+              (binary_operator
+                (identifier)
+                (identifier))
+              (binary_operator
+                (identifier)
+                (identifier))))
+          (identifier))))))
+
+=====================================
+nonempty list
+=====================================
+
+@spec fun() :: [integer, ...]
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (identifier)
+          (list
+            (call
+              (identifier))
+            (identifier)))))))
+
+=====================================
+[error] type guard cannot end with keyword separator
+=====================================
+
+@spec fun(arg) :: arg when arg: atom,
+
+---
+
+(source
+  (unary_operator
+    (call
+      (identifier)
+      (arguments
+        (binary_operator
+          (binary_operator
+            (call
+              (identifier)
+              (arguments
+                (identifier)))
+            (identifier))
+          (keywords
+            (pair
+              (keyword
+                (atom_literal))
+              (identifier)))))))
+  (ERROR))

test/corpus/semicolon.txt

@@ -0,0 +1,32 @@
+=====================================
+separates expressions in the same line
+=====================================
+
+1 ; 1
+
+---
+
+(source (integer) (integer))
+
+=====================================
+trailing
+=====================================
+
+1;
+2;
+
+---
+
+(source (integer) (integer))
+
+=====================================
+with comment
+=====================================
+
+1 ; # comment
+
+---
+
+(source
+  (integer)
+  (comment))

test/corpus/term/alias.txt

@@ -0,0 +1,88 @@
+=====================================
+single part
+=====================================
+
+Mod
+AZ_az_19_
+
+---
+
+(source
+  (alias)
+  (alias)
+  (alias))
+
+=====================================
+multiple parts
+=====================================
+
+Mod.Child
+Mod.Child.Child
+
+---
+
+(source
+  (alias)
+  (alias))
+
+=====================================
+qualified tuples
+=====================================
+
+Mod.{Child1, Child2}
+
+---
+
+(source
+  (dot
+    (alias)
+    (tuple
+      (alias)
+      (alias))))
+
+=====================================
+dot on identifier
+=====================================
+
+name.Mod
+name.Mod.Child
+
+---
+
+(source
+  (dot
+    (identifier)
+    (alias))
+  (dot
+    (identifier)
+    (alias)))
+
+=====================================
+dot on special identifier
+=====================================
+
+__MODULE__.Child
+
+(source
+  (dot
+    (special_identifier)
+    (alias)))
+
+=====================================
+[error] does not support characters outside ASCII
+=====================================
+
+Modこ
+Ólá
+Olá
+
+---
+
+(source
+  (alias)
+  (ERROR
+    (identifier))
+  (ERROR
+    (identifier))
+  (ERROR
+    (identifier)))

test/corpus/term/atom.txt

@@ -0,0 +1,95 @@
+=====================================
+simple literal
+=====================================
+
+:atom
+:_az_AZ_19_
+:nonode@nohost
+:bang!
+:question?
+
+---
+
+(source
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal)))
+
+=====================================
+operators
+=====================================
+
+[:~~~, :~>>, :~>, :|||, :||, :|>, :|, :>>>, :>=, :>, :=~, :===, :==, :=, :<~>, :<~, :<|>, :<>, :<=, :<<~, :<<<, :<-, :<, :+++, :++, :+, :^^^, :^, :&&&, :&&, :&, :\\, :/, :*, :@, :.., :., :!==, :!=, :!, :::, :->, :---, :--, :-]
+
+---
+
+(source
+  (list (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal)) (atom (atom_literal))))
+
+=====================================
+special operator-like atoms
+=====================================
+
+[:..., :%{}, :{}, :%, :<<>>, :..//]
+
+---
+
+(source
+  (list
+    (atom
+      (atom_literal))
+    (atom
+      (atom_literal))
+    (atom
+      (atom_literal))
+    (atom
+      (atom_literal))
+    (atom
+      (atom_literal))
+    (atom
+      (atom_literal))))
+
+=====================================
+quoted atom
+=====================================
+
+:"atom ?? !! ' \n"
+:'atom ?? !! " \n'
+
+---
+
+(source
+  (atom
+    (string_content)
+    (escape_sequence))
+  (atom
+    (string_content)
+    (escape_sequence)))
+
+=====================================
+interpolation
+=====================================
+
+:"hey #{name}!"
+:'hey #{name}!'
+
+---
+
+(source
+  (atom
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (atom
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content)))

test/corpus/term/bitstring.txt

@@ -0,0 +1,185 @@
+=====================================
+single item
+=====================================
+
+<<>>
+<<10>>
+<<10.0>>
+<<"string">>
+
+---
+
+(source
+  (bitstring)
+  (bitstring
+    (integer))
+  (bitstring
+    (float))
+  (bitstring
+    (string
+      (string_content))))
+
+=====================================
+multiple items
+=====================================
+
+<<
+  10,
+  10.0,
+  "string"
+>>
+
+---
+
+(source
+  (bitstring
+    (integer)
+    (float)
+    (string
+      (string_content))))
+
+=====================================
+size modifiers
+=====================================
+
+<<10::4>>
+<<10::size(4)>>
+
+---
+
+(source
+  (bitstring
+    (binary_operator
+      (integer)
+      (integer)))
+  (bitstring
+    (binary_operator
+      (integer)
+      (call
+        (identifier)
+        (arguments
+          (integer))))))
+
+=====================================
+multiple modifiers
+=====================================
+
+<<"string"::utf8-big>>
+<<"string"::utf16-big>>
+<<"string"::utf32-big>>
+<<10::32-little-unsigned>>
+<<10::integer-signed-big>>
+<<10.10::float-signed-native>>
+
+---
+
+(source
+  (bitstring
+    (binary_operator
+      (string
+        (string_content))
+      (binary_operator
+        (identifier)
+        (identifier)))
+    (binary_operator
+      (string
+        (string_content))
+      (binary_operator
+        (identifier)
+        (identifier)))
+    (binary_operator
+      (string
+        (string_content))
+      (binary_operator
+        (identifier)
+        (identifier)))
+    (binary_operator
+      (integer)
+      (binary_operator
+        (binary_operator
+          (integer)
+          (identifier))
+        (identifier)))
+    (binary_operator
+      (integer)
+      (binary_operator
+        (binary_operator
+          (identifier)
+          (identifier))
+        (identifier)))
+    (binary_operator
+      (float)
+      (binary_operator
+        (binary_operator
+          (identifier)
+          (identifier))
+        (identifier)))))
+
+=====================================
+multiple components with modifiers
+=====================================
+
+<<10::8-native, "string", 3.14::float, a::8, b::binary-size(known_size)>>
+
+---
+
+(source
+  (bitstring
+    (binary_operator
+      (integer)
+      (binary_operator
+        (integer)
+        (identifier)))
+    (string
+      (string_content))
+    (binary_operator
+      (float)
+      (identifier))
+    (binary_operator
+      (identifier)
+      (integer))
+    (binary_operator
+      (identifier)
+      (binary_operator
+        (identifier)
+        (call
+          (arguments
+            (identifier)))))))
+
+=====================================
+spacing
+=====================================
+
+<<
+  10 :: 8-native,
+  b :: binary - size(known_size)
+>>
+
+---
+
+(source
+  (bitstring
+    (binary_operator
+      (integer)
+      (binary_operator
+        (integer)
+        (identifier)))
+    (binary_operator
+      (identifier)
+      (binary_operator
+        (identifier)
+        (call
+          (arguments
+            (identifier)))))))
+
+=====================================
+trailing separator
+=====================================
+
+<<1,>>
+
+---
+
+(source
+  (bitstring
+    (integer)))

test/corpus/term/boolean.txt

@@ -0,0 +1,12 @@
+=====================================
+simple literal
+=====================================
+
+true
+false
+
+---
+
+(source
+  (boolean)
+  (boolean))

test/corpus/term/char.txt

@@ -0,0 +1,55 @@
+=====================================
+regular character
+=====================================
+
+?a
+?Z
+?0
+?9
+?_
+??
+
+---
+
+(source
+  (char)
+  (char)
+  (char)
+  (char)
+  (char)
+  (char))
+
+=====================================
+escaped character
+=====================================
+
+?\n
+?\t
+?\s
+?\\
+?\a
+?\b
+
+---
+
+(source
+  (char)
+  (char)
+  (char)
+  (char)
+  (char)
+  (char))
+
+=====================================
+list of char literals
+=====================================
+
+[?a, ?b, ?c]
+
+---
+
+(source
+  (list
+    (char)
+    (char)
+    (char)))

test/corpus/term/charlist.txt

@@ -0,0 +1,208 @@
+=====================================
+single line
+=====================================
+
+'Hello, 123!'
+
+---
+
+(source
+  (charlist
+    (string_content)))
+
+=====================================
+multiple lines
+=====================================
+
+'line 1
+line 2'
+
+---
+
+(source
+  (charlist
+    (string_content)))
+
+=====================================
+interpolation
+=====================================
+
+'hey #{name}!'
+'hey #{
+  name
+}!'
+'##{name}#'
+
+---
+
+(source
+  (charlist
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (charlist
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (charlist
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content)))
+
+=====================================
+nested interpolation
+=====================================
+
+'this is #{'number #{1}'}!'
+
+---
+
+(source
+  (charlist
+    (string_content)
+    (interpolation
+      (charlist
+        (string_content)
+        (interpolation
+          (identifier))))
+    (string_content)))
+
+=====================================
+escape sequence
+=====================================
+
+'_\'_\n_\t_\r_\e_\\_\1_\x3f_\u0065\u0301_'
+
+---
+
+(source
+  (charlist
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+escaped interpolation
+=====================================
+
+'\#{1}'
+
+---
+
+(source
+  (charlist
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+heredoc / charlist
+=====================================
+
+'''
+text
+with 'quotes'
+'''
+
+---
+
+(source
+  (charlist
+    (string_content)))
+
+=====================================
+heredoc / interpolation
+=====================================
+
+'''
+hey #{name}!
+'''
+
+---
+
+(source
+  (charlist
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content)))
+
+=====================================
+heredoc / nested interpolation
+=====================================
+
+'''
+this is #{
+  '''
+  number #{1}
+  '''
+}!
+'''
+
+---
+
+(source
+  (charlist
+    (string_content)
+    (interpolation
+      (charlist
+        (string_content)
+        (interpolation
+          (identifier))))
+    (string_content)))
+
+=====================================
+heredoc / escaped delimiter
+=====================================
+
+'''
+\'''
+'''
+
+'''
+\'\'\'
+'''
+
+---
+
+(source
+  (charlist
+    (escape_sequence)
+    (string_content)
+  (charlist
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+heredoc / escaped interpolation
+=====================================
+
+'''
+\#{1}
+'''
+
+---
+
+(source
+  (charlist
+    (escape_sequence)
+    (string_content)))

test/corpus/term/float.txt

@@ -0,0 +1,48 @@
+=====================================
+simple literal
+=====================================
+
+1234567890.1234567890
+-1234567890.1234567890
+-1_234_567_890.123_456_789_0
+
+---
+
+(source
+  (float)
+  (unary_operator
+    (float))
+  (unary_operator
+    (float)))
+
+=====================================
+scientific notation
+=====================================
+
+1.0e6
+1.0e+6
+1.0e-6
+-1.0e6
+-1.0e+6
+-1.0e-6
+1.0E6
+1.0E+6
+1.0E-6
+1_234_567_890.123_456_789_0e1_234_567_890
+
+---
+
+(source
+  (float)
+  (float)
+  (float)
+  (unary_operator
+    (float))
+  (unary_operator
+    (float))
+  (unary_operator
+    (float))
+  (float)
+  (float)
+  (float)
+  (float))

test/corpus/term/integer.txt

@@ -0,0 +1,66 @@
+=====================================
+decimal
+=====================================
+
+1234567890
+-1234567890
+1_234_567_890
+019
+
+---
+
+(source
+  (integer)
+  (unary_operator
+    (integer))
+  (integer)
+  (integer)
+  (integer))
+
+=====================================
+binary
+=====================================
+
+0b0101011
+-0b0101011
+0b0_10_10_11
+
+---
+
+(source
+  (integer)
+  (unary_operator
+    (integer))
+  (integer))
+
+=====================================
+octal
+=====================================
+
+0o1234567
+-0o1234567
+0o1_23_45_67
+
+---
+
+(source
+  (integer)
+  (unary_operator
+    (integer))
+  (integer))
+
+=====================================
+hexadecimal
+=====================================
+
+0x123456789abcdefABCDEF
+-0x123456789abcdefABCDEF
+0x123456789_abcdef_ABCDEF
+
+---
+
+(source
+  (integer)
+  (unary_operator
+    (integer))
+  (integer))

test/corpus/term/keyword_list.txt

@@ -0,0 +1,158 @@
+=====================================
+simple literal
+=====================================
+
+[a_b@12?: 1, A_B@12!: 2]
+
+---
+
+(source
+  (list
+    (keywords
+      (pair
+        (keyword
+          (atom_literal))
+        (integer))
+      (pair
+        (keyword
+          (atom_literal))
+        (integer)))))
+
+=====================================
+trailing separator
+=====================================
+
+[a: 1,]
+
+---
+
+(source
+  (list
+    (keywords
+      (pair
+        (keyword
+          (atom_literal))
+        (integer)))))
+
+=====================================
+with leading items
+=====================================
+
+[1, {:c, 1}, a: 1, b: 2]
+
+---
+
+(source
+  (list
+    (integer)
+    (tuple
+      (atom
+        (atom_literal))
+      (integer))
+    (keywords
+      (pair
+        (keyword
+          (atom_literal))
+        (integer))
+      (pair
+        (keyword
+          (atom_literal))
+        (integer)))))
+
+=====================================
+operator key
+=====================================
+
+[~~~: 1, ==: 2, >: 3]
+
+---
+
+(source
+  (list
+    (keywords
+      (pair
+        (keyword
+          (atom_literal))
+        (integer))
+      (pair
+        (keyword
+          (atom_literal))
+        (integer))
+      (pair
+        (keyword
+          (atom_literal))
+        (integer)))))
+
+=====================================
+quoted key
+=====================================
+
+[
+  "key1 ?? !! ' \n": 1,
+  'key2 ?? !! " \n': 2
+]
+
+---
+
+(source
+  (list
+    (keywords
+      (pair
+        (keyword
+          (string_content)
+          (escape_sequence))
+        (integer))
+      (pair
+        (keyword
+          (string_content)
+          (escape_sequence))
+        (integer)))))
+
+=====================================
+key interpolation
+=====================================
+
+[
+  "hey #{name}!": 1,
+  'hey #{name}!': 2
+]
+
+---
+
+(source
+  (list
+    (keywords
+      (pair
+        (keyword
+          (string_content)
+          (interpolation
+            (identifier))
+          (string_content))
+        (integer))
+      (pair
+        (keyword
+          (string_content)
+          (interpolation
+            (identifier))
+          (string_content))
+        (integer)))))
+
+=====================================
+[error] with trailing items
+=====================================
+
+[a: 1, b: 2, 1]
+
+---
+
+(source
+  (list
+    (ERROR
+      (keywords
+        (pair
+          (keyword
+            (atom_literal)))
+        (pair
+          (keyword
+            (atom_literal)))))
+    (integer)))

test/corpus/term/list.txt

@@ -0,0 +1,82 @@
+=====================================
+simple literal
+=====================================
+
+[]
+[1]
+[1, 2]
+[1,2]
+[ 1 , 2 ]
+
+---
+
+(source
+  (list)
+  (list
+    (integer))
+  (list
+    (integer)
+    (integer))
+  (list
+    (integer)
+    (integer))
+  (list
+    (integer)
+    (integer)))
+
+=====================================
+nested
+=====================================
+
+[[1], 1]
+
+---
+
+(source
+  (list
+    (list
+      (integer))
+    (integer)))
+
+=====================================
+trailing separator
+=====================================
+
+[1,]
+[1,2,]
+
+---
+
+(source
+  (list
+    (integer))
+  (list
+    (integer)
+    (integer)))
+
+=====================================
+[error] missing element
+=====================================
+
+[, 1]
+
+---
+
+(source
+  (list
+    (ERROR
+      (integer))))
+
+=====================================
+[error] missing separator
+=====================================
+
+[1 2]
+
+---
+
+(source
+  (list
+    (integer)
+    (ERROR
+      (integer))))

test/corpus/term/map.txt

@@ -0,0 +1,201 @@
+=====================================
+empty
+=====================================
+
+%{}
+
+---
+
+(source
+  (map))
+
+=====================================
+from keywords
+=====================================
+
+%{a: 1, b: 2}
+
+---
+
+(source
+  (map
+    (map_content
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+from arrow entries
+=====================================
+
+%{:a => 1, "b" => 2, c => 3}
+
+---
+
+(source
+  (map
+    (map_content
+      (binary_operator
+        (atom
+          (atom_literal))
+        (integer))
+      (binary_operator
+        (string
+          (string_content))
+        (integer))
+      (binary_operator
+        (identifier)
+        (integer)))))
+
+=====================================
+from both arrow entries and keywords
+=====================================
+
+%{"a" => 1, b: 2, c: 3}
+
+---
+
+(source
+  (map
+    (map_content
+      (binary_operator
+        (string
+          (string_content))
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+trailing separator
+=====================================
+
+%{"a" => 1,}
+
+---
+
+(source
+  (map
+    (map_content
+      (binary_operator
+        (string
+          (string_content))
+        (integer)))))
+
+=====================================
+update syntax
+=====================================
+
+%{user | name: "Jane", email: "jane@example.com"}
+%{user | "name" => "Jane"}
+
+---
+
+(source
+  (map
+    (map_content
+      (binary_operator
+        (identifier)
+        (keywords
+          (pair
+            (keyword
+              (atom_literal))
+            (string
+              (string_content)))
+          (pair
+            (keyword
+              (atom_literal))
+            (string
+              (string_content)))))))
+  (map
+    (map_content
+      (binary_operator
+        (identifier)
+        (binary_operator
+          (string
+            (string_content))
+          (integer))))))
+
+=====================================
+[error] ordering
+=====================================
+
+%{b: 2, c: 3, "a" => 1}
+
+---
+
+(source
+  (map
+    (map_content)
+      (ERROR
+        (keywords
+          (pair
+            (keyword
+              (atom_literal)))
+          (pair
+            (keyword
+              (atom_literal)))))
+      (binary_operator
+        (string
+          (string_content))
+        (integer))))
+
+=====================================
+[error] missing separator
+=====================================
+
+%{"a" => 1 "b" => 2}
+
+---
+
+(source
+  (map
+    (map_content)
+      (ERROR
+        (binary_operator
+          (string
+            (string_content))
+          (integer)))
+      (binary_operator
+        (string
+          (string_content))
+        (integer))))
+
+=====================================
+[error] invalid content
+=====================================
+
+%{1}
+%{1, 1}
+%{a, [], {}}
+
+---
+
+(source
+  (map
+    (map_content
+      (ERROR
+        (integer))))
+  (map
+    (map_content
+      (ERROR
+        (integer)
+        (integer))))
+  (map
+    (map_content
+      (ERROR
+        (identifier)
+        (list)
+        (tuple)))))

test/corpus/term/nil.txt

@@ -0,0 +1,10 @@
+=====================================
+simple literal
+=====================================
+
+nil
+
+---
+
+(source
+  (nil))

test/corpus/term/string.txt

@@ -0,0 +1,220 @@
+=====================================
+single line
+=====================================
+
+"Hello, 123!"
+
+---
+
+(source
+  (string
+    (string_content)))
+
+=====================================
+multiple lines
+=====================================
+
+"line 1
+line 2"
+
+---
+
+(source
+  (string
+    (string_content)))
+
+=====================================
+interpolation
+=====================================
+
+"hey #{name}!"
+"hey #{
+  name
+}!"
+"##{name}#"
+
+---
+
+(source
+  (string
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (string
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content))
+  (string
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content)))
+
+=====================================
+nested interpolation
+=====================================
+
+"this is #{"number #{1}"}!"
+
+---
+
+(source
+  (string
+    (string_content)
+    (interpolation
+      (string
+        (string_content)
+        (interpolation
+          (identifier))))
+    (string_content)))
+
+=====================================
+escape sequence
+=====================================
+
+"_\"_\n_\t_\r_\e_\\_\1_\x3f_\u0065\u0301_"
+
+---
+
+(source
+  (string
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (string_content)
+    (escape_sequence)
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+escaped interpolation
+=====================================
+
+"\#{1}"
+
+---
+
+(source
+  (string
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+heredoc / string
+=====================================
+
+"""
+text
+with "quotes"
+"""
+
+---
+
+(source
+  (string
+    (string_content)))
+
+=====================================
+heredoc / interpolation
+=====================================
+
+"""
+hey #{name}!
+"""
+
+---
+
+(source
+  (string
+    (string_content)
+    (interpolation
+      (identifier))
+    (string_content)))
+
+=====================================
+heredoc / nested interpolation
+=====================================
+
+"""
+this is #{
+  """
+  number #{1}
+  """
+}!
+"""
+
+---
+
+(source
+  (string
+    (string_content)
+    (interpolation
+      (string
+        (string_content)
+        (interpolation
+          (identifier))))
+    (string_content)))
+
+=====================================
+heredoc / escaped delimiter
+=====================================
+
+"""
+\"""
+"""
+
+"""
+\"\"\"
+"""
+
+---
+
+(source
+  (string
+    (escape_sequence)
+    (string_content)
+  (string
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+heredoc / escaped interpolation
+=====================================
+
+"""
+\#{1}
+"""
+
+---
+
+(source
+  (string
+    (escape_sequence)
+    (string_content)))
+
+=====================================
+[error] heredoc / no whitespace
+=====================================
+
+"""s"""
+
+---
+
+(source
+  (ERROR
+    (identifier)))

test/corpus/term/struct.txt

@@ -0,0 +1,201 @@
+=====================================
+empty
+=====================================
+
+%User{}
+
+---
+
+(source
+  (map
+    (struct
+      (alias))))
+
+=====================================
+from keywords
+=====================================
+
+%User{a: 1, b: 2}
+
+---
+
+(source
+  (map
+    (struct
+      (alias))
+    (map_content
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+from arrow entries
+=====================================
+
+%User{:a => 1, "b" => 2, c => 3}
+
+---
+
+(source
+  (map
+    (struct
+      (alias))
+    (map_content
+      (binary_operator
+        (atom
+          (atom_literal))
+        (integer))
+      (binary_operator
+        (string
+          (string_content))
+        (integer))
+      (binary_operator
+        (identifier)
+        (integer)))))
+
+=====================================
+from both arrow entries and keywords
+=====================================
+
+%User{"a" => 1, b: 2, c: 3}
+
+---
+
+(source
+  (map
+    (struct
+      (alias))
+    (map_content
+      (binary_operator
+        (string
+          (string_content))
+        (integer))
+      (keywords
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))
+        (pair
+          (keyword
+            (atom_literal))
+          (integer))))))
+
+=====================================
+trailing separator
+=====================================
+
+%User{"a" => 1,}
+
+---
+
+(source
+  (map
+    (struct
+      (alias))
+    (map_content
+      (binary_operator
+        (string
+          (string_content))
+        (integer)))))
+
+=====================================
+update syntax
+=====================================
+
+%User{user | name: "Jane", email: "jane@example.com"}
+%User{user | "name" => "Jane"}
+
+---
+
+(source
+  (map
+    (struct (alias))
+    (map_content
+      (binary_operator
+        (identifier)
+        (keywords
+          (pair
+            (keyword
+              (atom_literal))
+            (string
+              (string_content)))
+          (pair
+            (keyword
+              (atom_literal))
+            (string
+              (string_content)))))))
+  (map
+    (struct
+      (alias))
+    (map_content
+      (binary_operator
+        (identifier)
+        (binary_operator
+          (string
+            (string_content))
+          (integer))))))
+
+=====================================
+unused struct identifier
+=====================================
+
+%_{}
+
+---
+
+(source
+  (map
+    (struct
+      (unused_identifier))))
+
+=====================================
+matching struct identifier
+=====================================
+
+%name{}
+
+---
+
+(source
+  (map
+    (struct
+      (identifier))))
+
+=====================================
+pinned struct identifier
+=====================================
+
+%^name{}
+
+---
+
+(source
+  (map
+    (struct
+      (unary_operator
+        (identifier)))))
+
+=====================================
+with special identifier
+=====================================
+
+%__MODULE__{}
+%__MODULE__.Child{}
+
+---
+
+(source
+  (map
+    (struct
+      (special_identifier)))
+  (map
+    (struct
+      (dot
+        (special_identifier)
+        (alias)))))

test/corpus/term/tuple.txt

@@ -0,0 +1,82 @@
+=====================================
+simple literal
+=====================================
+
+{}
+{1}
+{1, 2}
+{1,2}
+{ 1 , 2 }
+
+---
+
+(source
+  (tuple)
+  (tuple
+    (integer))
+  (tuple
+    (integer)
+    (integer))
+  (tuple
+    (integer)
+    (integer))
+  (tuple
+    (integer)
+    (integer)))
+
+=====================================
+nested
+=====================================
+
+{{1}, 1}
+
+---
+
+(source
+  (tuple
+    (tuple
+      (integer))
+    (integer)))
+
+=====================================
+trailing separator
+=====================================
+
+{1,}
+{1,2,}
+
+---
+
+(source
+  (tuple
+    (integer))
+  (tuple
+    (integer)
+    (integer)))
+
+=====================================
+[error] missing element
+=====================================
+
+{, 1}
+
+---
+
+(source
+  (tuple
+    (ERROR
+      (integer))))
+
+=====================================
+[error] missing separator
+=====================================
+
+{1 2}
+
+---
+
+(source
+  (tuple
+    (integer)
+    (ERROR
+      (integer))))

test/corpus/unicode.txt

@@ -0,0 +1,114 @@
+=====================================
+atom
+=====================================
+
+:time_μs
+:"£"
+:'£'
+:こんにちは世界
+:Ólá
+:olá
+:Olá
+
+---
+
+(source
+  (atom
+    (atom_literal))
+  (atom
+    (string_content))
+  (atom
+    (string_content))
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal))
+  (atom
+    (atom_literal)))
+
+=====================================
+string
+=====================================
+
+"time_μs"
+"£"
+"こんにちは世界"
+"Ólá"
+"olá"
+"Olá"
+
+---
+
+(source
+  (string
+    (string_content))
+  (string
+    (string_content))
+  (string
+    (string_content))
+  (string
+    (string_content))
+  (string
+    (string_content))
+  (string
+    (string_content)))
+
+=====================================
+charlist
+=====================================
+
+'time_μs'
+'£'
+'こんにちは世界'
+'Ólá'
+'olá'
+'Olá'
+---
+
+(source
+  (charlist
+    (string_content))
+  (charlist
+    (string_content))
+  (charlist
+    (string_content))
+  (charlist
+    (string_content))
+  (charlist
+    (string_content))
+  (charlist
+    (string_content)))
+
+=====================================
+char
+=====================================
+
+?ł
+?μ
+?£
+?こ
+
+---
+
+(source
+  (char)
+  (char)
+  (char)
+  (char))
+
+=====================================
+variable
+=====================================
+
+time_μs
+こんにちは世界
+olá
+
+---
+
+(source
+  (identifier)
+  (identifier)
+  (identifier))

test/corpus/variable.txt

@@ -0,0 +1,63 @@
+=====================================
+regular
+=====================================
+
+snake_case
+camelCase
+az_AZ_19
+bang!
+question?
+__TEST__
+doctest
+not1
+notfalse
+
+---
+
+(source
+  (identifier)
+  (identifier)
+  (identifier)
+  (identifier)
+  (identifier)
+  (identifier)
+  (identifier)
+  (identifier)
+  (identifier))
+
+=====================================
+unused
+=====================================
+
+_
+_number
+
+---
+
+(source
+  (unused_identifier)
+  (unused_identifier))
+
+=====================================
+three dots identifier
+=====================================
+
+...
+
+---
+
+(source
+  (identifier))
+
+=====================================
+special identifier
+=====================================
+
+__MODULE__
+__DIR__
+
+---
+
+(source
+  (special_identifier)
+  (special_identifier))