Fix: glob processing (fixes #11940)

lib/cli-engine/file-enumerator.js

@@ -289,31 +289,32 @@ class FileEnumerator {
      * @param {string} pattern The glob pattern to iterate files.
      * @returns {IterableIterator<FileEntry>} The found files.
      */
-    _iterateFiles(pattern) {
+    *_iterateFiles(pattern) {
         const { cwd, globInputPaths } = internalSlotsMap.get(this);
         const absolutePath = path.resolve(cwd, pattern);
+        const isDot = dotfilesPattern.test(pattern);
 
         if (globInputPaths && isGlobPattern(pattern)) {
-            return this._iterateFilesWithGlob(
-                absolutePath,
-                dotfilesPattern.test(pattern)
-            );
+            let found = false;
+
+            for (const entry of this._iterateFilesWithGlob(absolutePath, isDot)) {
+                found = true;
+                yield entry;
+            }
+
+            // If the glob didn't match any files, fall it through as a filename.
+            if (found) {
+                return;
+            }
         }
 
         const stat = statSafeSync(absolutePath);
 
         if (stat && stat.isDirectory()) {
-            return this._iterateFilesWithDirectory(
-                absolutePath,
-                dotfilesPattern.test(pattern)
-            );
-        }
-
-        if (stat && stat.isFile()) {
-            return this._iterateFilesWithFile(absolutePath);
+            yield* this._iterateFilesWithDirectory(absolutePath, isDot);
+        } else if (stat && stat.isFile()) {
+            yield* this._iterateFilesWithFile(absolutePath);
         }
-
-        return [];
     }
 
     /**

tests/lib/cli-engine/cli-engine.js

@@ -3454,6 +3454,46 @@ describe("CLIEngine", () => {
                 assert.strictEqual(report.results[0].messages[0].message, "ok");
             });
         });
+
+        describe("glob pattern '[ab].js'", () => {
+            const root = getFixturePath("cli-engine/unmatched-glob");
+
+            it("should match 'a.js' and 'b.js', but not '[ab].js'.", () => {
+                CLIEngine = defineCLIEngineWithInMemoryFileSystem({
+                    cwd: () => root,
+                    files: {
+                        "a.js": "",
+                        "b.js": "",
+                        "ab.js": "",
+                        "[ab].js": "",
+                        ".eslintrc.yml": "root: true"
+                    }
+                }).CLIEngine;
+                engine = new CLIEngine();
+
+                const { results } = engine.executeOnFiles(["[ab].js"]);
+                const filenames = results.map(r => path.basename(r.filePath));
+
+                assert.deepStrictEqual(filenames, ["a.js", "b.js"]);
+            });
+
+            it("should match '[ab].js' if both 'a.js' and 'b.js' didn't exist.", () => {
+                CLIEngine = defineCLIEngineWithInMemoryFileSystem({
+                    cwd: () => root,
+                    files: {
+                        "ab.js": "",
+                        "[ab].js": "",
+                        ".eslintrc.yml": "root: true"
+                    }
+                }).CLIEngine;
+                engine = new CLIEngine();
+
+                const { results } = engine.executeOnFiles(["[ab].js"]);
+                const filenames = results.map(r => path.basename(r.filePath));
+
+                assert.deepStrictEqual(filenames, ["[ab].js"]);
+            });
+        });
     });
 
     describe("getConfigForFile", () => {