implement getOriginalLocationOfAtValue

packages/happy-css-modules/src/locator/postcss.test.ts

@@ -14,6 +14,7 @@ import {
   parseAtValue,
   parseComposesDeclarationWithFromUrl,
   collectNodes,
+  getOriginalLocationOfAtValue,
 } from './postcss.js';
 
 describe('generateLocalTokenNames', () => {
@@ -313,6 +314,17 @@ describe('getOriginalLocationOfClassSelector', () => {
   });
 });
 
+test('getOriginalLocationOfAtValue', () => {
+  const [basic] = createAtValues(
+    createRoot(dedent`
+    @value basic: #000;
+    `),
+  );
+  expect(getOriginalLocationOfAtValue(basic!)).toMatchInlineSnapshot(
+    `{ filePath: "/test/test.css", start: { line: 1, column: 1 }, end: { line: 1, column: 19 } }`,
+  );
+});
+
 test('collectNodes', () => {
   const ast = createRoot(dedent`
     @import;

packages/happy-css-modules/src/locator/postcss.ts

@@ -114,6 +114,32 @@ export function getOriginalLocationOfClassSelector(rule: Rule, classSelector: Cl
   };
 }
 
+/**
+ * Get the original location of `@value`.
+ * @param atValue The `@value` rule.
+ * @returns The location of the `@value` rule.
+ */
+export function getOriginalLocationOfAtValue(atValue: AtRule): Location {
+  // The node derived from `postcss.parse` always has `source` property. Therefore, this line is unreachable.
+  if (atValue.source === undefined) throw new Error('Node#source is undefined');
+  // The node derived from `postcss.parse` always has `start` and `end` property. Therefore, this line is unreachable.
+  if (atValue.source.start === undefined) throw new Error('Node#start is undefined');
+  if (atValue.source.end === undefined) throw new Error('Node#end is undefined');
+  if (atValue.source.input.file === undefined) throw new Error('Node#input.file is undefined');
+
+  return {
+    filePath: atValue.source.input.file,
+    start: {
+      line: atValue.source.start.line,
+      column: atValue.source.start.column,
+    },
+    end: {
+      line: atValue.source.end.line,
+      column: atValue.source.end.column,
+    },
+  };
+}
+
 function isAtRuleNode(node: Node): node is AtRule {
   return node.type === 'atrule';
 }