Support @layer at rules

internal/stylance-core/src/parse.rs

@@ -204,12 +204,19 @@ fn at_rule<'s>(input: &mut &'s str) -> PResult<Vec<CssFragment<'s>>> {
         return Ok(vec![]);
     }
 
-    if identifier == "media" {
-        cut_err(terminated(style_rule_block_contents, '}')).parse_next(input)
-    } else {
-        cut_err(terminated(unknown_block_contents, '}')).parse_next(input)?;
-        Ok(vec![])
+    match identifier {
+        "media" | "layer" => cut_err(terminated(style_rule_block_contents, '}')).parse_next(input),
+        _ => {
+            cut_err(terminated(unknown_block_contents, '}')).parse_next(input)?;
+            Ok(vec![])
+        }
     }
+    // if identifier == "media" {
+    //     cut_err(terminated(style_rule_block_contents, '}')).parse_next(input)
+    // } else {
+    //     cut_err(terminated(unknown_block_contents, '}')).parse_next(input)?;
+    //     Ok(vec![])
+    // }
 }
 
 fn unknown_block_contents<'s>(input: &mut &'s str) -> PResult<&'s str> {
@@ -359,6 +366,35 @@ mod tests {
         assert!(input.is_empty());
     }
 
+    #[test]
+    fn test_at_rule_layer() {
+        let mut input = "@layer test {
+        .foo {
+            background-color: red;
+        }
+
+        .bar {
+            color: blue;
+
+            .baz {
+                color: green;
+            }
+        }
+    }";
+
+        let r = at_rule.parse_next(&mut input);
+        assert_eq!(
+            r,
+            Ok(vec![
+                CssFragment::Class("foo"),
+                CssFragment::Class("bar"),
+                CssFragment::Class("baz")
+            ])
+        );
+
+        assert!(input.is_empty());
+    }
+
     #[test]
     fn test_top_level() {
         let mut input = "// tool.module.scss
@@ -376,6 +412,14 @@ mod tests {
             }
         }
 
+        @layer {
+            .foo {
+                color: blue;
+            }
+        }
+
+        @layer foo;
+
         @debug 1+2 * 3==1+(2 * 3); // true
 
         .container {
@@ -401,6 +445,7 @@ mod tests {
             Ok(vec![
                 CssFragment::Class("default_border"),
                 CssFragment::Class("foo"),
+                CssFragment::Class("foo"),
                 CssFragment::Class("container"),
                 CssFragment::Class("bar"),
             ])

stylance/tests/style.module.scss

@@ -67,4 +67,16 @@ $some-scss-variable: 10px; // Scss variable declarations in top scope.
 // scss placeholder class should parse
 %scss-class {
 	color: red;
-}
+}
+
+@layer test-layer {
+	.style8 {
+		color: red;
+	}
+}
+
+@layer test-layer2;
+
+@layer;
+
+//eof

stylance/tests/test_import_styles.rs

@@ -10,6 +10,8 @@ fn test_import_crate_style() {
     assert_eq!(style::style4, "style4-a331da9");
     assert_eq!(style::style5, "style5-a331da9");
     assert_eq!(style::style6, "style6-a331da9");
+    assert_eq!(style::style7, "style7-a331da9");
+    assert_eq!(style::style8, "style8-a331da9");
 
     assert_eq!(style::style_with_dashes, "style-with-dashes-a331da9");
     assert_eq!(style::nested_style, "nested-style-a331da9");
@@ -36,6 +38,8 @@ fn test_import_style() {
     assert_eq!(style::style4, "style4-a331da9");
     assert_eq!(style::style5, "style5-a331da9");
     assert_eq!(style::style6, "style6-a331da9");
+    assert_eq!(style::style7, "style7-a331da9");
+    assert_eq!(style::style8, "style8-a331da9");
 
     assert_eq!(style::style_with_dashes, "style-with-dashes-a331da9");
     assert_eq!(style::nested_style, "nested-style-a331da9");