chore: resolve comment issues

Author: ggodlewski

lib/cli/watch-run.js

@@ -137,6 +137,40 @@ exports.watchRun = (mocha, {watchFiles, watchIgnore}, fileCollectParams) => {
   });
 };
 
+class GlobFilesTracker {
+  constructor(watchFiles, watchIgnore) {
+    this.watchFilesSet = new Set();
+    this.watchFiles = watchFiles;
+    this.watchIgnore = watchIgnore;
+  }
+
+  regenerate() {
+    let watchIgnoreFlat = [];
+    for (const pattern of this.watchIgnore) {
+      watchIgnoreFlat = watchIgnoreFlat.concat(glob.sync(pattern, { dot: true }));
+    }
+
+    this.watchFilesSet.clear();
+    for (const pattern of this.watchFiles) {
+      glob.sync(pattern, { dot: true }).forEach(pathToCheck => {
+        for (const watchIgnore of watchIgnoreFlat) {
+          if (pathToCheck === watchIgnore) {
+            return;
+          }
+          if (pathToCheck.startsWith(watchIgnore + path.sep)) {
+            return;
+          }
+        }
+        this.watchFilesSet.add(pathToCheck);
+      });
+    }
+  }
+
+  has(filePath) {
+    return this.watchFilesSet.has(filePath)
+  }
+}
+
 /**
  * Bootstraps a chokidar watcher. Handles keyboard input & signals
  * @param {Mocha} mocha - Mocha instance
@@ -168,34 +202,8 @@ const createWatcher = (
   // we handle global fixtures manually
   mocha.enableGlobalSetup(false).enableGlobalTeardown(false);
 
-  const watchFilesFlat = [];
-
-  const regenerateWatchFilesFlat = () => {
-    let watchIgnoreFlat = [];
-    for (const pattern of watchIgnore) {
-      watchIgnoreFlat = watchIgnoreFlat.concat(glob.sync(pattern, { dot: true }));
-    }
-
-    let newWatchFilesFlat = [];
-    for (const pattern of watchFiles) {
-      newWatchFilesFlat = newWatchFilesFlat.concat(
-        glob.sync(pattern, { dot: true }).filter(pathToCheck => {
-          for (const watchIgnore of watchIgnoreFlat) {
-            if (pathToCheck === watchIgnore) {
-              return false;
-            }
-            if (pathToCheck.startsWith(watchIgnore + path.sep)) {
-              return false;
-            }
-          }
-          return true;
-        }));
-    }
-    watchFilesFlat.splice(0, watchFiles.length);
-    watchFilesFlat.push(...newWatchFilesFlat);
-  }
-
-  regenerateWatchFilesFlat();
+  const tracker = new GlobFilesTracker(watchFiles, watchIgnore);
+  tracker.regenerate();
 
   const watcher = chokidar.watch('.', {
     ignoreInitial: true
@@ -214,15 +222,11 @@ const createWatcher = (
   });
 
   watcher.on('all', (event, filePath) => {
-    if (watchFilesFlat.includes(filePath)) {
+    if (event === 'add') {
+      tracker.regenerate();
+    }
+    if (tracker.has(filePath)) {
       rerunner.scheduleRun();
-    } else {
-      if (event === 'add') {
-        regenerateWatchFilesFlat();
-        if (watchFilesFlat.includes(filePath)) {
-          rerunner.scheduleRun();
-        }
-      }
     }
   });