fix: handle function in watchOptions.ignored (#600)

Author: piotr-oles

src/watch/InclusiveNodeWatchFileSystem.ts

@@ -12,14 +12,19 @@ function createIsIgnored(
   ignored: WatchFileSystemOptions['ignored'] | undefined
 ): (path: string) => boolean {
   const ignoredPatterns = ignored ? (Array.isArray(ignored) ? ignored : [ignored]) : [];
-  const ignoredFunctions = ignoredPatterns
-    // sanitize patterns - see https://github.com/TypeStrong/fork-ts-checker-webpack-plugin/issues/594
-    .filter((pattern) => typeof pattern === 'string' || pattern instanceof RegExp)
-    .map((pattern) =>
-      pattern instanceof RegExp
-        ? (path: string) => pattern.test(path)
-        : (path: string) => minimatch(path, pattern)
-    );
+  const ignoredFunctions = ignoredPatterns.map((pattern) => {
+    // ensure patterns are valid - see https://github.com/TypeStrong/fork-ts-checker-webpack-plugin/issues/594
+    if (typeof pattern === 'string') {
+      return (path: string) => minimatch(path, pattern);
+    } else if (typeof pattern === 'function') {
+      return pattern;
+    } else if (pattern instanceof RegExp) {
+      return (path: string) => pattern.test(path);
+    } else {
+      // fallback to no-ignore function
+      return () => false;
+    }
+  });
   ignoredFunctions.push((path: string) =>
     BUILTIN_IGNORED_DIRS.some((ignoredDir) => path.includes(`/${ignoredDir}/`))
   );

src/watch/WatchFileSystem.ts

@@ -4,7 +4,7 @@ interface WatchFileSystemOptions {
   aggregateTimeout: number;
   poll: boolean;
   followSymlinks: boolean;
-  ignored: string | RegExp | (string | RegExp)[];
+  ignored: string | RegExp | Function | (string | RegExp | Function)[];
 }
 
 // watchpack v1 and v2 internal interface

test/e2e/TypeScriptWatchApi.spec.ts

@@ -414,6 +414,12 @@ describe('TypeScript Watch API', () => {
     { webpack: '4.0.0', async: false, ignored: '[path.resolve(__dirname, "src/model/**")]' },
     { webpack: '^4.0.0', async: true, ignored: '"**/src/model/**"' },
     { webpack: '^5.0.0', async: false, ignored: '/src\\/model/' },
+    {
+      webpack: '^4.0.0',
+      async: true,
+      ignored:
+        '(file) => forwardSlash(file).includes(forwardSlash(path.resolve(__dirname, "src/model/")))',
+    },
   ])('ignores directories from watch with %p', async ({ webpack, async, ignored }) => {
     await sandbox.load([
       await readFixture(join(__dirname, 'fixtures/environment/typescript-basic.fixture'), {
@@ -430,6 +436,16 @@ describe('TypeScript Watch API', () => {
       await readFixture(join(__dirname, 'fixtures/implementation/typescript-basic.fixture')),
     ]);
 
+    await sandbox.patch(
+      'webpack.config.js',
+      'module.exports = {',
+      [
+        'function forwardSlash(input) {',
+        "  return path.normalize(input).replace(/\\\\+/g, '/');",
+        '}',
+        'module.exports = {',
+      ].join('\n')
+    );
     await sandbox.patch(
       'webpack.config.js',
       "  entry: './src/index.ts',",
@@ -453,7 +469,11 @@ describe('TypeScript Watch API', () => {
     await sandbox.write('src/model/Group.ts', '// TODO: to implement');
 
     // there should be no re-build
-    await expect(driver.waitForErrors(3000)).rejects.toBeDefined();
-    await expect(driver.waitForNoErrors(3000)).rejects.toBeDefined();
+    await expect(driver.waitForNoErrors(3000)).rejects.toEqual(
+      new Error('Exceeded time on waiting for no errors message to appear.')
+    );
+    await expect(driver.waitForErrors(3000)).rejects.toEqual(
+      new Error('Exceeded time on waiting for errors to appear.')
+    );
   });
 });