feat: use FlatESLint instead of loadEslint

sarbbottam · Oct 6, 2024 · b690889 · b690889
1 parent dfd671e
commit b690889
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Showing 2 changed files with 129 additions and 104 deletions.
diff --git a/src/lib/rule-finder.js b/src/lib/rule-finder.js
@@ -1,26 +1,28 @@
 const path = require('path');
 
-const { ESLint, Linter, loadESLint } = require('eslint');
+const { ESLint, Linter } = require('eslint');
 const glob = require('glob');
 const difference = require('./array-diff');
 const getSortedRules = require('./sort-rules');
 const normalizePluginName = require('./normalize-plugin-name');
 
-let builtinRules;
+let builtinRules, FlatESLint;
 try {
-  builtinRules = require('eslint/use-at-your-own-risk').builtinRules;
+  const eslintInternal = require('eslint/use-at-your-own-risk');
+  builtinRules = eslintInternal.builtinRules;
+  FlatESLint = eslintInternal.FlatESLint;
 } catch (e) {}
 
-async function _loadEslint(options, useFlatConfig) {
+function _loadEslint(options, useFlatConfig) {
   if (!useFlatConfig) {
     // Ignore any config applicable depending on the location on the filesystem
     options.useEslintrc = false;
-  } else if (!loadESLint) {
+  } else if (!FlatESLint) {
     throw 'This version of ESLint does not support flat config.';
   }
 
-  return loadESLint
-    ? new (await loadESLint({ useFlatConfig }))(options)
+  return useFlatConfig
+    ? new FlatESLint(options)
     : new ESLint(options);
 }
 
@@ -36,7 +38,7 @@ function _getConfigFile(specifiedFile) {
 }
 
 async function _getConfigs(overrideConfigFile, files, useFlatConfig) {
-  const esLint = await _loadEslint({
+  const esLint = _loadEslint({
     // Point to the particular config
     overrideConfigFile
   }, useFlatConfig);

diff --git a/test/lib/rule-finder.js b/test/lib/rule-finder.js
@@ -163,6 +163,19 @@ const getRuleFinderForDedupeTests = proxyquire('../../src/lib/rule-finder', {
   }
 });
 
+const getRuleFinderNoFlatSupport = proxyquire('../../src/lib/rule-finder', {
+  eslint: {
+    Linter: class {
+      getRules() {
+        return mockedBuiltinRules
+      }
+    },
+  },
+  'eslint/use-at-your-own-risk': {
+    FlatESLint: undefined
+  }
+});
+
 const noSpecifiedFile = path.resolve(process.cwd(), `./test/fixtures/${eslintVersion}/no-path`);
 const specifiedFileRelative = `./test/fixtures/${eslintVersion}/eslint.json`;
 const specifiedFileAbsolute = path.join(process.cwd(), specifiedFileRelative);
@@ -652,111 +665,121 @@ describe('rule-finder', function() {
     ]);
   });
 
+  it('flat config - should throw an exception if FlatESLint is not defined', async () => {
+    try {
+      await getRuleFinderNoFlatSupport(specifiedFlatConfigFileRelative, {useFlatConfig: true})
+      assert.fail('Expected an error to be thrown');
+    } catch (error) {
+      assert.strictEqual(error, 'This version of ESLint does not support flat config.')
+    }
+  });
 
-  describe('flat config', () => {
-    it('specifiedFile (relative path) - unused rules', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getUnusedRules(), [
-        'bar-rule',
-        'baz-rule',
-        'plugin/bar-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - unused rules including deprecated', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {includeDeprecated: true, useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getUnusedRules(), [
-        'bar-rule',
-        'baz-rule',
-        'old-rule',
-        'plugin/bar-rule',
-        'plugin/old-plugin-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - current rules', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getCurrentRules(), [
-        'foo-rule',
-        'plugin/foo-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - current rules with ext', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { ext: ['.json'], useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getCurrentRules(), [
-        'jsonPlugin/foo-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - current rules with ext without dot', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { ext: ['json'], useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getCurrentRules(), [
-        'jsonPlugin/foo-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - current rules with ext not found', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { ext: ['.ts'], useFlatConfig: true });
-      assert.deepEqual(ruleFinder.getCurrentRules(), []);
-    });
-
-    it('specifiedFile (relative path) - plugin rules', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getPluginRules(), [
-        'plugin/bar-rule',
-        'plugin/foo-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - plugin rules including deprecated', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {includeDeprecated: true, useFlatConfig: true});
-      assert.deepEqual(ruleFinder.getPluginRules(), [
-        'plugin/bar-rule',
-        'plugin/foo-rule',
-        'plugin/old-plugin-rule'
-      ]);
-    });
-
-    it('specifiedFile (relative path) - all available rules', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { useFlatConfig: true });
-      assert.deepEqual(
-        ruleFinder.getAllAvailableRules(),
-        [
+  if (semver.satisfies(eslintPkg.version, '>= 8')) {
+    describe('flat config - supported', () => {
+      it('specifiedFile (relative path) - unused rules', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getUnusedRules(), [
           'bar-rule',
           'baz-rule',
-          'foo-rule',
+          'plugin/bar-rule'
+        ]);
+      });
+
+      it('specifiedFile (relative path) - unused rules including deprecated', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {includeDeprecated: true, useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getUnusedRules(), [
+          'bar-rule',
+          'baz-rule',
+          'old-rule',
           'plugin/bar-rule',
+          'plugin/old-plugin-rule'
+        ]);
+      });
+
+      it('specifiedFile (relative path) - current rules', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getCurrentRules(), [
+          'foo-rule',
           'plugin/foo-rule'
-        ]
-      );
-    });
-
-    it('specifiedFile (relative path) - all available rules without core', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {omitCore: true, useFlatConfig: true});
-      assert.deepEqual(
-        ruleFinder.getAllAvailableRules(),
-        [
+        ]);
+      });
+
+      it('specifiedFile (relative path) - current rules with ext', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { ext: ['.json'], useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getCurrentRules(), [
+          'jsonPlugin/foo-rule'
+        ]);
+      });
+
+      it('specifiedFile (relative path) - current rules with ext without dot', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { ext: ['json'], useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getCurrentRules(), [
+          'jsonPlugin/foo-rule'
+        ]);
+      });
+
+      it('specifiedFile (relative path) - current rules with ext not found', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { ext: ['.ts'], useFlatConfig: true });
+        assert.deepEqual(ruleFinder.getCurrentRules(), []);
+      });
+
+      it('specifiedFile (relative path) - plugin rules', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getPluginRules(), [
           'plugin/bar-rule',
           'plugin/foo-rule'
-        ]
-      );
-    });
-
-    it('specifiedFile (relative path) - all available rules including deprecated', async () => {
-      const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {includeDeprecated: true, useFlatConfig: true});
-      assert.deepEqual(
-        ruleFinder.getAllAvailableRules(),
-        [
-          'bar-rule',
-          'baz-rule',
-          'foo-rule',
-          'old-rule',
+        ]);
+      });
+
+      it('specifiedFile (relative path) - plugin rules including deprecated', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {includeDeprecated: true, useFlatConfig: true});
+        assert.deepEqual(ruleFinder.getPluginRules(), [
           'plugin/bar-rule',
           'plugin/foo-rule',
           'plugin/old-plugin-rule'
-        ]
-      );
+        ]);
+      });
+
+      it('specifiedFile (relative path) - all available rules', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, { useFlatConfig: true });
+        assert.deepEqual(
+          ruleFinder.getAllAvailableRules(),
+          [
+            'bar-rule',
+            'baz-rule',
+            'foo-rule',
+            'plugin/bar-rule',
+            'plugin/foo-rule'
+          ]
+        );
+      });
+
+      it('specifiedFile (relative path) - all available rules without core', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {omitCore: true, useFlatConfig: true});
+        assert.deepEqual(
+          ruleFinder.getAllAvailableRules(),
+          [
+            'plugin/bar-rule',
+            'plugin/foo-rule'
+          ]
+        );
+      });
+
+      it('specifiedFile (relative path) - all available rules including deprecated', async () => {
+        const ruleFinder = await getRuleFinder(specifiedFlatConfigFileRelative, {includeDeprecated: true, useFlatConfig: true});
+        assert.deepEqual(
+          ruleFinder.getAllAvailableRules(),
+          [
+            'bar-rule',
+            'baz-rule',
+            'foo-rule',
+            'old-rule',
+            'plugin/bar-rule',
+            'plugin/foo-rule',
+            'plugin/old-plugin-rule'
+          ]
+        );
+      });
     });
-  })
+  }
 });