refactor parsing of media queries to use predicate parsing

src/parse/media.rs

@@ -1,9 +1,6 @@
 use crate::{
     error::SassResult,
-    utils::{
+    utils::{is_name_start, peek_ident_no_interpolation},
-        is_name_start, peek_ident_no_interpolation, read_until_closing_paren,
-        read_until_closing_quote,
-    },
     {Cow, Token},
 };
 
@@ -35,38 +32,25 @@ impl<'a> Parser<'a> {
         false
     }
 
-    // todo: replace with predicate
     pub fn expression_until_comparison(&mut self) -> SassResult<Cow<'static, str>> {
-        let mut toks = Vec::new();
+        let value = self.parse_value(false, &|toks| match toks.peek() {
-        while let Some(tok) = self.toks.peek().cloned() {
+            Some(Token { kind: '>', .. })
-            match tok.kind {
+            | Some(Token { kind: '<', .. })
-                '=' => {
+            | Some(Token { kind: ':', .. })
-                    self.toks.advance_cursor();
+            | Some(Token { kind: ')', .. }) => true,
-                    if matches!(self.toks.peek(), Some(Token { kind: '=', .. })) {
+            Some(Token { kind: '=', .. }) => {
-                        self.toks.reset_cursor();
+                if matches!(toks.peek_next(), Some(Token { kind: '=', .. })) {
-                        break;
+                    toks.reset_cursor();
-                    }
+                    true
-                    self.toks.reset_cursor();
+                } else {
-                    toks.push(tok);
+                    toks.reset_cursor();
-                    toks.push(tok);
+                    false
-                    self.toks.next();
-                    self.toks.next();
-                }
-                '>' | '<' | ':' | ')' => {
-                    break;
-                }
-                '\'' | '"' => {
-                    toks.push(tok);
-                    self.toks.next();
-                    toks.append(&mut read_until_closing_quote(self.toks, tok.kind)?);
-                }
-                _ => {
-                    toks.push(tok);
-                    self.toks.next();
                 }
             }
-        }
+            _ => false,
-        self.parse_value_as_string_from_vec(toks, false)
+        })?;
+
+        value.node.unquote().to_css_string(value.span)
     }
 
     pub(super) fn parse_media_query_list(&mut self) -> SassResult<String> {
@@ -85,13 +69,10 @@ impl<'a> Parser<'a> {
 
     fn parse_media_feature(&mut self) -> SassResult<String> {
         if let Some(Token { kind: '#', .. }) = self.toks.peek() {
-            if let Some(Token { kind: '{', .. }) = self.toks.peek_forward(1) {
-                self.toks.next();
             self.toks.next();
+            self.expect_char('{')?;
             return Ok(self.parse_interpolation_as_string()?.into_owned());
         }
-            todo!()
-        }
         let mut buf = String::with_capacity(2);
         self.expect_char('(')?;
         buf.push('(');
@@ -105,13 +86,14 @@ impl<'a> Parser<'a> {
 
             buf.push(':');
             buf.push(' ');
-            let mut toks = read_until_closing_paren(self.toks)?;
+
-            if let Some(tok) = toks.pop() {
+            let value = self.parse_value(false, &|toks| match toks.peek() {
-                if tok.kind != ')' {
+                Some(Token { kind: ')', .. }) => true,
-                    todo!()
+                _ => false,
-                }
+            })?;
-            }
+            self.expect_char(')')?;
-            buf.push_str(&self.parse_value_as_string_from_vec(toks, true)?);
+
+            buf.push_str(&value.node.to_css_string(value.span)?);
 
             self.whitespace_or_comment();
             buf.push(')');

src/parse/mod.rs

@@ -531,19 +531,7 @@ impl<'a> Parser<'a> {
         })
     }
 
-    pub fn parse_value_as_string_from_vec(
+    // todo: this should also consume silent comments
-        &mut self,
-        toks: Vec<Token>,
-        quoted: bool,
-    ) -> SassResult<Cow<'static, str>> {
-        let value = self.parse_value_from_vec(toks, false)?;
-        if quoted {
-            value.node.to_css_string(value.span)
-        } else {
-            value.node.unquote().to_css_string(value.span)
-        }
-    }
-
     pub fn whitespace(&mut self) -> bool {
         let mut found_whitespace = false;
         while let Some(tok) = self.toks.peek() {

tests/media.rs

@@ -72,3 +72,29 @@ test!(
     }",
     "@media foo and (bar) {\n  a {\n    color: red;\n  }\n}\n"
 );
+test!(
+    comparison_in_query,
+    "@media (100px < 400px) {
+        a {
+            interpolation: in-parens
+        }
+    }",
+    "@media (100px < 400px) {\n  a {\n    interpolation: in-parens;\n  }\n}\n"
+);
+test!(
+    interpolated_comparison_in_query,
+    "@media (#{100px < 400px}) {
+        a {
+            interpolation: in-parens
+        }
+    }",
+    "@media (true) {\n  a {\n    interpolation: in-parens;\n  }\n}\n"
+);
+error!(
+    media_feature_missing_closing_paren,
+    "@media foo and (bar:a", "Error: expected \")\"."
+);
+error!(
+    media_feature_missing_curly_brace_after_hash,
+    "@media foo and # {}", "Error: expected \"{\"."
+);