Allow shell-expanded strings in attributes (#3007)

Author: casey

src/parser.rs

@@ -1348,7 +1348,7 @@ impl<'run, 'src> Parser<'run, 'src> {
           arguments.push(self.parse_string_literal_token()?);
         } else if self.accepted(ParenL)? {
           loop {
-            if self.next_is(Identifier) {
+            if self.next_is(Identifier) && !self.next_is_shell_expanded_string() {
               let name = self.parse_name()?;
 
               self.expect(Equals)?;

tests/attributes.rs

@@ -311,3 +311,15 @@ fn duplicate_non_repeatable_attributes_are_forbidden() {
     .status(EXIT_FAILURE)
     .run();
 }
+
+#[test]
+fn shell_expanded_strings_can_be_used_in_attributes() {
+  Test::new()
+    .justfile(
+      "
+        [doc(x'foo')]
+        bar:
+      ",
+    )
+    .run();
+}