initial implementation of varargs

src/args.rs

@@ -37,11 +37,21 @@ enum CallArg {
     Positional(usize),
 }
 
+impl CallArg {
+    pub fn position(&self) -> SassResult<usize> {
+        match self {
+            Self::Named(..) => todo!(),
+            Self::Positional(p) => Ok(*p),
+        }
+    }
+}
+
 impl CallArgs {
     pub fn new() -> Self {
         CallArgs(HashMap::new())
     }
 
+    #[allow(dead_code)]
     pub fn get_named(&self, val: String) -> Option<&Value> {
         self.0.get(&CallArg::Named(val))
     }
@@ -50,6 +60,20 @@ impl CallArgs {
         self.0.get(&CallArg::Positional(val))
     }
 
+    pub fn get_variadic(self) -> SassResult<Value> {
+        let mut vals = Vec::new();
+        let mut args = self
+            .0
+            .into_iter()
+            .map(|(a, v)| Ok((a.position()?, v)))
+            .collect::<SassResult<Vec<(usize, Value)>>>()?;
+        args.sort_by(|(a1, _), (a2, _)| a1.cmp(a2));
+        for arg in args {
+            vals.push(arg.1);
+        }
+        Ok(Value::ArgList(vals))
+    }
+
     pub fn len(&self) -> usize {
         self.0.len()
     }

src/atrule/function.rs

@@ -43,8 +43,12 @@ impl Function {
         Ok((name, Function::new(scope, args, body)))
     }
 
-    pub fn args(mut self, args: &mut CallArgs) -> SassResult<Function> {
+    pub fn args(mut self, mut args: CallArgs) -> SassResult<Function> {
         for (idx, arg) in self.args.0.iter().enumerate() {
+            if arg.is_variadic {
+                self.scope.insert_var(&arg.name, args.get_variadic()?)?;
+                break;
+            }
             let val = match args.remove_positional(idx) {
                 Some(v) => v,
                 None => match args.remove_named(arg.name.clone()) {

src/atrule/mixin.rs

@@ -59,8 +59,12 @@ impl Mixin {
         self
     }
 
-    pub fn args(mut self, args: &mut CallArgs) -> SassResult<Mixin> {
+    pub fn args(mut self, mut args: CallArgs) -> SassResult<Mixin> {
         for (idx, arg) in self.args.0.iter().enumerate() {
+            if arg.is_variadic {
+                self.scope.insert_var(&arg.name, args.get_variadic()?)?;
+                break;
+            }
             let val = match args.remove_positional(idx) {
                 Some(v) => v,
                 None => match args.remove_named(arg.name.clone()) {
@@ -128,7 +132,7 @@ pub(crate) fn eat_include<I: Iterator<Item = Token>>(
 
     let mut has_include = false;
 
-    let mut args = if let Some(tok) = toks.next() {
+    let args = if let Some(tok) = toks.next() {
         match tok.kind {
             ';' => CallArgs::new(),
             '(' => {
@@ -170,9 +174,6 @@ pub(crate) fn eat_include<I: Iterator<Item = Token>>(
 
     let mixin = scope.get_mixin(&name)?.clone();
 
-    let rules = mixin
-        .args(&mut args)?
-        .content(content)
-        .call(super_selector)?;
+    let rules = mixin.args(args)?.content(content).call(super_selector)?;
     Ok(rules)
 }

src/value/mod.rs

@@ -29,6 +29,7 @@ pub(crate) enum Value {
     Paren(Box<Value>),
     Ident(String, QuoteKind),
     Map(SassMap),
+    ArgList(Vec<Value>),
     // Returned by `get-function()`
     // Function(String)
 }
@@ -120,6 +121,15 @@ impl Display for Value {
             Self::True => write!(f, "true"),
             Self::False => write!(f, "false"),
             Self::Null => write!(f, "null"),
+            Self::ArgList(args) => write!(
+                f,
+                "{}",
+                args.iter()
+                    .filter(|x| !x.is_null())
+                    .map(std::string::ToString::to_string)
+                    .collect::<Vec<String>>()
+                    .join(", "),
+            ),
         }
     }
 }
@@ -157,6 +167,7 @@ impl Value {
             Self::Dimension(..) => Ok("number"),
             Self::List(..) => Ok("list"),
             // Self::Function(..) => Ok("function"),
+            Self::ArgList(..) => Ok("arglist"),
             Self::True | Self::False => Ok("bool"),
             Self::Null => Ok("null"),
             Self::Map(..) => Ok("map"),

src/value/ops.rs

@@ -14,7 +14,7 @@ impl Add for Value {
         }
         let precedence = Op::Plus.precedence();
         Ok(match self {
-            Self::Map(..) => todo!(),
+            Self::ArgList(..) | Self::Map(..) => todo!(),
             Self::Important | Self::True | Self::False => match other {
                 Self::Ident(s, QuoteKind::Double) | Self::Ident(s, QuoteKind::Single) => {
                     Value::Ident(format!("{}{}", self, s), QuoteKind::Double)
@@ -86,7 +86,7 @@ impl Add for Value {
                 Self::List(..) => Value::Ident(format!("{}{}", s1, other), quotes1),
                 Self::UnaryOp(..) | Self::BinaryOp(..) => todo!(),
                 Self::Paren(..) => (Self::Ident(s1, quotes1) + other.eval()?)?,
-                Self::Map(..) => todo!(),
+                Self::ArgList(..) | Self::Map(..) => todo!(),
             },
             Self::List(..) => match other {
                 Self::Ident(s, q) => Value::Ident(format!("{}{}", self, s), q.normalize()),

src/value/parse.rs

@@ -406,7 +406,7 @@ impl Value {
                 };
                 Ok(IntermediateValue::Value(
                     func.clone()
-                        .args(&mut eat_call_args(toks, scope, super_selector)?)?
+                        .args(eat_call_args(toks, scope, super_selector)?)?
                         .call(super_selector, func.body())?,
                 ))
             }

tests/args.rs

@@ -15,3 +15,13 @@ error!(
     varargs_two_periods,
     "@function foo($a..) {\n  @return $a;\n}\n", "Error: expected \".\"."
 );
+test!(
+    mixin_varargs_are_comma_separated,
+    "@mixin foo($a...) {\n  color: $a;\n}\n\na {\n  @include foo(1, 2, 3, 4, 5);\n}\n",
+    "a {\n  color: 1, 2, 3, 4, 5;\n}\n"
+);
+test!(
+    function_varargs_are_comma_separated,
+    "@function foo($a...) {\n  @return $a;\n}\n\na {\n  color: foo(1, 2, 3, 4, 5);\n}\n",
+    "a {\n  color: 1, 2, 3, 4, 5;\n}\n"
+);

tests/meta.rs

@@ -164,6 +164,11 @@ test!(
     "a {\n  color: type-of(hi + bye)\n}\n",
     "a {\n  color: string;\n}\n"
 );
+test!(
+    type_of_arglist,
+    "@mixin foo($a...) {color: type-of($a);}\na {@include foo(1, 2, 3, 4, 5);}",
+    "a {\n  color: arglist;\n}\n"
+);
 test!(
     unitless_px,
     "a {\n  color: unitless(1px)\n}\n",