Merge pull request #104 from ember-tooling/thow-usable-eslint-error

throw useful error message for eslint

Author: NullVoxPopuli

scripts/eslint-plugin-ember-test.mjs

@@ -13,7 +13,6 @@ await fse.ensureDir(FOLDERS.testRoot);
 
 // Using pnpm instead of yarn, because pnpm is way faster
 await execaCommand(`git clone ${REPO}`, { cwd: FOLDERS.testRoot, stdio: 'inherit' });
-await execaCommand(`pnpm import`, { cwd: FOLDERS.repo, stdio: 'inherit' }); // project uses a yarn lockfile
 await execaCommand(`pnpm install`, { cwd: FOLDERS.repo, stdio: 'inherit' });
 await execaCommand(`pnpm add ${FOLDERS.here}`, { cwd: FOLDERS.repo, stdio: 'inherit' });
 await execaCommand(`pnpm run test`, { cwd: FOLDERS.repo, stdio: 'inherit' });

src/parser/gjs-gts-parser.js

@@ -29,7 +29,7 @@ module.exports = {
     patchTs();
     registerParsedFile(options.filePath);
     let jsCode = code;
-    const info = transformForLint(code);
+    const info = transformForLint(code, options.filePath);
     jsCode = info.output;
 
     const isTypescript = options.filePath.endsWith('.gts') || options.filePath.endsWith('.ts');

src/parser/transforms.js

@@ -567,7 +567,39 @@ module.exports.replaceRange = replaceRange;
 
 const processor = new ContentTag.Preprocessor();
 
-module.exports.transformForLint = function transformForLint(code) {
+class EmberParserError extends Error {
+  constructor(message, fileName, location) {
+    super(message);
+    this.location = location;
+    this.fileName = fileName;
+    Object.defineProperty(this, 'name', {
+      configurable: true,
+      enumerable: false,
+      value: new.target.name,
+    });
+  }
+
+  // For old version of ESLint https://github.com/typescript-eslint/typescript-eslint/pull/6556#discussion_r1123237311
+  get index() {
+    return this.location.start.offset;
+  }
+
+  // https://github.com/eslint/eslint/blob/b09a512107249a4eb19ef5a37b0bd672266eafdb/lib/linter/linter.js#L853
+  get lineNumber() {
+    return this.location.start.line;
+  }
+
+  // https://github.com/eslint/eslint/blob/b09a512107249a4eb19ef5a37b0bd672266eafdb/lib/linter/linter.js#L854
+  get column() {
+    return this.location.start.column;
+  }
+}
+
+function createError(code, message, fileName, start, end = start) {
+  return new EmberParserError(message, fileName, { end, start });
+}
+
+module.exports.transformForLint = function transformForLint(code, fileName) {
   let jsCode = code;
   /**
    *
@@ -593,7 +625,26 @@ module.exports.transformForLint = function transformForLint(code) {
    *   };
    * }[]}
    */
-  const result = processor.parse(code);
+  let result = null;
+  try {
+    result = processor.parse(code);
+  } catch (e) {
+    // Parse Error at <anon>:1:19: 1:19
+    if (e.message.includes('Parse Error at')) {
+      const [line, column] = e.message
+        .split(':')
+        .slice(-2)
+        .map((x) => parseInt(x));
+      // e.source_code has actually usable info, e.g × Expected ',', got 'string literal (, '')'
+      //     ╭─[9:1]
+      //   9 │
+      //  10 │ console.log(test'');
+      //     ·                 ──
+      //     ╰────
+      throw createError(code, e.source_code, fileName, { line, column });
+    }
+    throw e;
+  }
   for (const tplInfo of result.reverse()) {
     const content = tplInfo.contents.replace(/`/g, '\\`').replace(/\$/g, '\\$');
     if (tplInfo.type === 'class-member') {

test-projects/gjs/package.json

@@ -2,7 +2,9 @@
   "name": "@test-project/gjs",
   "private": true,
   "scripts": {
-    "test": "eslint . --max-warnings=0"
+    "test": "pnpm run /test:.*/",
+    "test:correct-handle-syntax-error": "eslint . | grep -q '26:15  error  Parsing error: × Unexpected eof'",
+    "test:only-one-error": "eslint --format compact .  | egrep '^[0-9]+ problem[s]*' | wc -l | grep -q 1"
   },
   "devDependencies": {
     "@typescript-eslint/eslint-plugin": "^6.21.0",

test-projects/gjs/src/placeholer.gjs

@@ -21,3 +21,6 @@ export const Placeholder = <template>
     ><code class="{{orGlimdown (qp 'format')}} hljs">{{context.text}}</code></pre>
   {{/let}}
 </template>;
+
+
+console.log(')

tests/parser.test.js

@@ -2677,4 +2677,28 @@ export const NotFound = <template>
       }
     `);
   });
+
+  it('throws eslint syntax error', () => {
+    try {
+      result = parseForESLint(`console.log('test)`, {
+        filePath: 'example.gts',
+        comment: true,
+        loc: true,
+        range: true,
+        tokens: true,
+      });
+    } catch (e) {
+      expect(e.lineNumber).toBe(1);
+      expect(e.column).toBe(19);
+      expect(e.fileName).toBe('example.gts');
+      expect(e.message).toMatchInlineSnapshot(`
+        "
+          × Unexpected eof
+           ╭────
+         1 │ console.log('test)
+           ╰────
+        "
+      `);
+    }
+  });
 });