span_before in quoted string

src/selector/attribute.rs

@@ -123,7 +123,7 @@ impl Attribute {
         let value = match peek.kind {
             q @ '\'' | q @ '"' => {
                 toks.next();
-                match parse_quoted_string(toks, scope, q, super_selector)?.node {
+                match parse_quoted_string(toks, scope, q, super_selector, span_before)?.node {
                     Value::String(s, ..) => s,
                     _ => unreachable!(),
                 }

src/stylesheet.rs

@@ -256,6 +256,7 @@ impl<'a> StyleSheetParser<'a> {
                                             &Scope::new(),
                                             q,
                                             &Selector::new(),
+                                            next.pos,
                                         )?
                                         .node
                                         .unquote()

src/utils/strings.rs

@@ -281,13 +281,13 @@ pub(crate) fn parse_quoted_string<I: Iterator<Item = Token>>(
     scope: &Scope,
     q: char,
     super_selector: &Selector,
+    span_before: Span,
 ) -> SassResult<Spanned<Value>> {
     let mut s = String::new();
-    let mut span = if let Some(tok) = toks.peek() {
-        tok.pos()
-    } else {
-        todo!()
-    };
+    let mut span = toks
+        .peek()
+        .ok_or((format!("Expected {}.", q), span_before))?
+        .pos();
     while let Some(tok) = toks.next() {
         span = span.merge(tok.pos());
         match tok.kind {

src/value/parse.rs

@@ -823,7 +823,7 @@ impl Value {
             q @ '"' | q @ '\'' => {
                 let span_start = toks.next().unwrap().pos();
                 let Spanned { node, span } =
-                    match parse_quoted_string(toks, scope, q, super_selector) {
+                    match parse_quoted_string(toks, scope, q, super_selector, span_start) {
                         Ok(v) => v,
                         Err(e) => return Some(Err(e)),
                     };

tests/error.rs

@@ -224,7 +224,9 @@ error!(
     ident_colon_closing_brace,
     "r:}", "Error: Expected expression."
 );
+error!(dollar_sign_alone, "$", "Error: Expected identifier.");
 error!(
-    dollar_sign_alone,
-    "$", "Error: Expected identifier."
+    nothing_after_dbl_quote,
+    "a {color: \"", "Error: Expected \"."
 );
+error!(nothing_after_sgl_quote, "a {color: '", "Error: Expected '.");