Merge pull request #54 from tree-sitter/ns/ansii-c-quoting

Support ANSII-C quoting in strings prefixed with $

corpus/literals.txt

@@ -299,6 +299,16 @@ echo "s$"
   (command (command_name (word)) (string))
   (command (command_name (word)) (string)))
 
+========================================
+Strings with ANSI-C quoting
+========================================
+
+echo $'Here\'s johnny!\r\n'
+
+---
+
+(program (command (command_name (word)) (ansii_c_string)))
+
 =========================================
 Arrays and array expansions
 =========================================

grammar.js

@@ -396,6 +396,7 @@ module.exports = grammar({
       $.word,
       $.string,
       $.raw_string,
+      $.ansii_c_string,
       $.expansion,
       $.simple_expansion,
       $.string_expansion,
@@ -445,6 +446,8 @@ module.exports = grammar({
 
     raw_string: $ => /'[^']*'/,
 
+    ansii_c_string: $ => /\$'([^']|\\')*'/,
+
     simple_expansion: $ => seq(
       '$',
       choice(

src/grammar.json

@@ -1626,6 +1626,10 @@
           "type": "SYMBOL",
           "name": "raw_string"
         },
+        {
+          "type": "SYMBOL",
+          "name": "ansii_c_string"
+        },
         {
           "type": "SYMBOL",
           "name": "expansion"
@@ -1866,6 +1870,10 @@
       "type": "PATTERN",
       "value": "'[^']*'"
     },
+    "ansii_c_string": {
+      "type": "PATTERN",
+      "value": "\\$'([^']|\\\\')*'"
+    },
     "simple_expansion": {
       "type": "SEQ",
       "members": [

src/tree_sitter/parser.h

@@ -122,22 +122,26 @@ struct TSLanguage {
 
 #define START_LEXER()           \
   bool result = false;          \
+  bool skip = false;            \
   int32_t lookahead;            \
+  goto start;                   \
   next_state:                   \
+  lexer->advance(lexer, skip);  \
+  start:                        \
+  skip = false;                 \
   lookahead = lexer->lookahead;
 
-#define ADVANCE(state_value)      \
-  {                               \
-    lexer->advance(lexer, false); \
-    state = state_value;          \
-    goto next_state;              \
+#define ADVANCE(state_value) \
+  {                          \
+    state = state_value;     \
+    goto next_state;         \
   }
 
-#define SKIP(state_value)        \
-  {                              \
-    lexer->advance(lexer, true); \
-    state = state_value;         \
-    goto next_state;             \
+#define SKIP(state_value) \
+  {                       \
+    skip = true;          \
+    state = state_value;  \
+    goto next_state;      \
   }
 
 #define ACCEPT_TOKEN(symbol_value)     \