Convert remove-redundant-flags script into linter and fixer (mdn#21512)

scripts/fix/flags.test.ts

@@ -0,0 +1,266 @@
+/* This file is a part of @mdn/browser-compat-data
+ * See LICENSE file for more information. */
+
+import assert from 'node:assert/strict';
+
+import { SupportStatement } from '../../types/types.js';
+
+import { removeIrrelevantFlags } from './flags.js';
+
+const tests: { input: SupportStatement; output: SupportStatement }[] = [
+  {
+    input: [
+      {
+        version_added: '70',
+      },
+      {
+        version_added: '21',
+        version_removed: '65',
+        flags: [
+          {
+            type: 'preference',
+            name: '#service-worker-payment-apps',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+    ],
+    output: {
+      version_added: '70',
+    },
+  },
+  {
+    input: [
+      {
+        version_added: '62',
+      },
+      {
+        version_added: '21',
+        version_removed: '80',
+        flags: [
+          {
+            type: 'preference',
+            name: '#service-worker-payment-apps',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+    ],
+    output: {
+      version_added: '62',
+    },
+  },
+  {
+    input: [
+      {
+        version_added: '62',
+      },
+      {
+        version_added: '21',
+        flags: [
+          {
+            type: 'preference',
+            name: '#service-worker-payment-apps',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+    ],
+    output: {
+      version_added: '62',
+    },
+  },
+  {
+    input: [
+      {
+        version_added: '42',
+        flags: [
+          {
+            type: 'preference',
+            name: '#enable-experimental-web-features',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+      {
+        version_added: '21',
+        version_removed: '45',
+        flags: [
+          {
+            type: 'preference',
+            name: '#service-worker-payment-apps',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+    ],
+    output: {
+      version_added: '42',
+      flags: [
+        {
+          type: 'preference',
+          name: '#enable-experimental-web-features',
+          value_to_set: 'Enabled',
+        },
+      ],
+    },
+  },
+  {
+    input: {
+      version_added: '42',
+      version_removed: '43',
+      flags: [
+        {
+          type: 'preference',
+          name: '#enable-experimental-web-features',
+          value_to_set: 'Enabled',
+        },
+      ],
+    },
+    output: {
+      version_added: false,
+    },
+  },
+  {
+    input: [
+      {
+        version_added: '80',
+      },
+      {
+        version_added: '21',
+        version_removed: '80',
+        flags: [
+          {
+            type: 'preference',
+            name: '#service-worker-payment-apps',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+    ],
+    output: {
+      version_added: '80',
+    },
+  },
+  {
+    input: [
+      {
+        version_added: '79',
+        flags: [
+          {
+            type: 'preference',
+            name: 'enable-experimental-web-platform-features',
+            value_to_set: 'enabled',
+          },
+        ],
+      },
+      {
+        version_added: '12',
+        version_removed: '79',
+      },
+    ],
+    output: [
+      {
+        version_added: '79',
+        flags: [
+          {
+            type: 'preference',
+            name: 'enable-experimental-web-platform-features',
+            value_to_set: 'enabled',
+          },
+        ],
+      },
+      {
+        version_added: '12',
+        version_removed: '79',
+      },
+    ],
+  },
+  {
+    input: [
+      {
+        version_added: '86',
+      },
+      {
+        version_added: '21',
+        flags: [
+          {
+            type: 'preference',
+            name: '#service-worker-payment-apps',
+            value_to_set: 'Enabled',
+          },
+        ],
+      },
+    ],
+    output: {
+      version_added: '86',
+    },
+  },
+  {
+    input: [
+      {
+        version_added: '79',
+        version_removed: '80',
+        flags: [
+          {
+            type: 'preference',
+            name: 'WebVR',
+          },
+        ],
+      },
+      {
+        version_added: '15',
+        version_removed: '79',
+      },
+    ],
+    output: {
+      version_added: '15',
+      version_removed: '79',
+    },
+  },
+  {
+    input: [
+      {
+        version_added: 'preview',
+      },
+      {
+        version_added: '105',
+        flags: [
+          {
+            type: 'preference',
+            name: 'layout.css.font-tech.enabled',
+            value_to_set: 'true',
+          },
+        ],
+      },
+    ],
+    output: [
+      {
+        version_added: 'preview',
+      },
+      {
+        version_added: '105',
+        flags: [
+          {
+            type: 'preference',
+            name: 'layout.css.font-tech.enabled',
+            value_to_set: 'true',
+          },
+        ],
+      },
+    ],
+  },
+];
+
+describe('fix -> flags', () => {
+  let i = 1;
+  for (const test of tests) {
+    it(`Test #${i}`, () => {
+      const result = removeIrrelevantFlags(test.input);
+
+      assert.deepStrictEqual(result, test.output);
+    });
+
+    i += 1;
+  }
+});

scripts/fix/flags.ts

@@ -0,0 +1,92 @@
+/* This file is a part of @mdn/browser-compat-data
+ * See LICENSE file for more information. */
+
+import fs from 'node:fs';
+
+import {
+  BrowserName,
+  SupportStatement,
+  SimpleSupportStatement,
+} from '../../types/types.js';
+import { IS_WINDOWS } from '../../test/utils.js';
+import testFlags, {
+  isIrrelevantFlagData,
+  getBasicSupportStatement,
+} from '../../test/linter/test-flags.js';
+import walk from '../../utils/walk.js';
+
+/**
+ * Removes irrelevant flags from the compatibility data
+ * @param supportData The compatibility statement to test
+ * @returns The compatibility statement with all of the flags removed
+ */
+export const removeIrrelevantFlags = (
+  supportData: SupportStatement,
+): SupportStatement => {
+  if (typeof supportData === 'string') {
+    return supportData;
+  }
+
+  if (!Array.isArray(supportData)) {
+    if (isIrrelevantFlagData(supportData, undefined)) {
+      return { version_added: false };
+    }
+
+    return supportData;
+  }
+
+  const result: SimpleSupportStatement[] = [];
+  const basicSupport = getBasicSupportStatement(supportData);
+
+  for (const statement of supportData) {
+    if (!isIrrelevantFlagData(statement, basicSupport)) {
+      result.push(statement);
+    }
+  }
+
+  if (result.length == 0) {
+    return { version_added: false };
+  }
+  if (result.length == 1) {
+    return result[0];
+  }
+  return result;
+};
+
+/**
+ * Removes irrelevant flags from the compatibility data of a specified file
+ * @param filename The filename containing compatibility info
+ */
+const fixFlags = (filename: string): void => {
+  let actual = fs.readFileSync(filename, 'utf-8').trim();
+
+  const data = JSON.parse(actual);
+  const walker = walk(undefined, data);
+
+  for (const feature of walker) {
+    if (testFlags.exceptions?.includes(feature.path)) {
+      continue;
+    }
+
+    for (const [browser, supportData] of Object.entries(
+      feature.compat.support,
+    ) as [BrowserName, SupportStatement][]) {
+      feature.data.__compat.support[browser] =
+        removeIrrelevantFlags(supportData);
+    }
+  }
+
+  let expected = JSON.stringify(data, null, 2);
+
+  if (IS_WINDOWS) {
+    // prevent false positives from git.core.autocrlf on Windows
+    actual = actual.replace(/\r/g, '');
+    expected = expected.replace(/\r/g, '');
+  }
+
+  if (actual !== expected) {
+    fs.writeFileSync(filename, expected + '\n', 'utf-8');
+  }
+};
+
+export default fixFlags;

scripts/fix/index.ts

@@ -13,6 +13,7 @@ import fixBrowserOrder from './browser-order.js';
 import fixFeatureOrder from './feature-order.js';
 import fixPropertyOrder from './property-order.js';
 import fixStatementOrder from './statement-order.js';
+import fixFlags from './flags.js';
 import fixLinks from './links.js';
 import fixStatus from './status.js';
 import fixMirror from './mirror.js';
@@ -45,6 +46,7 @@ const load = async (...files: string[]): Promise<void> => {
           fixBrowserOrder(file);
           fixFeatureOrder(file);
           fixStatementOrder(file);
+          fixFlags(file);
           fixLinks(file);
           fixStatus(file);
           fixMirror(file);