Bugfix: useSourceHash (#28) Generate source hash on emit because afterEmit only has SizeOnlySource

Feature: New option `useSourceSize` to compare source sizes

Author: web-mi

README.md

@@ -46,6 +46,7 @@ Add a script tag to your page pointed at the livereload server
   ignore nothing. It is also possible to define an array and use multiple [anymatch](https://github.com/micromatch/anymatch) patterns.
 - `delay` - (Default: `0`) amount of milliseconds by which to delay the live reload (in case build takes longer)
 - `useSourceHash` - (Default: `false`) create hash for each file source and only notify livereload if hash has changed
+- `useSourceSize` - (Default: `false`) check size for each file source and only notify livereload if size has changed (Faster than `useSourceHash` but it has a downside. If file size hasn't changed no reload is triggered. For example if color has changed from `#000000` to `#ffffff` no reload will be triggered!)
 
 ## Why?
 

index.js

@@ -25,6 +25,7 @@ class LiveReloadPlugin {
       ignore: null,
       quiet: false,
       useSourceHash: false,
+      useSourceSize: false,
       appendScriptTag: false,
       delay: 0,
     }, options);
@@ -35,6 +36,7 @@ class LiveReloadPlugin {
     this.lastChildHashes = [];
     this.server = null;
     this.sourceHashs = {};
+    this.sourceSizes = {};
     this.webpack = null;
     this.infrastructureLogger = null;
     this.isWebpack4 = false;
@@ -47,7 +49,8 @@ class LiveReloadPlugin {
 
     compiler.hooks.compilation.tap(PLUGIN_NAME, this._applyCompilation.bind(this));
     compiler.hooks.watchRun.tapAsync(PLUGIN_NAME, this._start.bind(this));
-    compiler.hooks.afterEmit.tap(PLUGIN_NAME, this._afterEmit.bind(this))
+    compiler.hooks.afterEmit.tap(PLUGIN_NAME, this._afterEmit.bind(this));
+    compiler.hooks.emit.tap(PLUGIN_NAME, this._emit.bind(this));
     compiler.hooks.failed.tap(PLUGIN_NAME, this._failed.bind(this));
   }
 
@@ -145,6 +148,7 @@ class LiveReloadPlugin {
 
     const include = Object.entries(compilation.assets)
         .filter(this._fileIgnoredOrNotEmitted.bind(this))
+        .filter(this._fileSizeDoesntMatch.bind(this))
         .filter(this._fileHashDoesntMatch.bind(this))
         .map((data) => data[0])
     ;
@@ -162,13 +166,22 @@ class LiveReloadPlugin {
     }
   }
 
+  /**
+   * @private
+   * @param compilation
+   */
+  _emit(compilation) {
+    Object.entries(compilation.assets).forEach(this._calculateSourceHash.bind(this));
+  }
+
   /**
    * @private
    */
   _failed() {
     this.lastHash = null;
     this.lastChildHashes = [];
     this.sourceHashs = {};
+    this.sourceSizes = {};
   }
 
   /**
@@ -225,6 +238,25 @@ class LiveReloadPlugin {
     return !data[0].match(this.options.ignore) && size;
   }
 
+  /**
+   * Check compiled source size
+   *
+   * @param data
+   * @returns {boolean}
+   * @private
+   */
+  _fileSizeDoesntMatch(data) {
+    if (!this.options.useSourceSize)
+      return true;
+
+    if (this.sourceSizes[data[0]] === data[1].size()) {
+      return false;
+    }
+
+    this.sourceSizes[data[0]] = data[1].size();
+    return true;
+  }
+
   /**
    * Check compiled source hash
    *
@@ -236,16 +268,32 @@ class LiveReloadPlugin {
     if (!this.options.useSourceHash)
       return true;
 
-    const sourceHash = LiveReloadPlugin.generateHashCode(data[1].source());
-
-    if (this.sourceHashs[data[0]] === sourceHash) {
+    if (this.sourceHashs[data[0]]?.hash === this.sourceHashs[data[0]].calculated) {
       return false;
     }
 
-    this.sourceHashs[data[0]] = sourceHash;
+    // Update source hash
+    this.sourceHashs[data[0]].hash = this.sourceHashs[data[0]].calculated;
     return true;
   }
 
+  /**
+   * Calculate compiled source hash
+   *
+   * @param data
+   * @returns {void}
+   * @private
+   */
+  _calculateSourceHash(data) {
+    if (!this.options.useSourceHash) return;
+
+    // Calculate source hash
+    this.sourceHashs[data[0]] = {
+      hash: this.sourceHashs[data[0]]?.hash ?? null,
+      calculated: LiveReloadPlugin.generateHashCode(data[1].source())
+    };
+  }
+
   /**
    * @private
    */

test.js

@@ -10,6 +10,7 @@ test('default options', function(t) {
   t.equal(plugin.options.ignore, null);
   t.equal(plugin.options.quiet, false);
   t.equal(plugin.options.useSourceHash, false);
+  t.equal(plugin.options.useSourceSize, false);
   t.equal(plugin.options.appendScriptTag, false);
   t.equal(plugin.options.delay, 0);
   t.equal(plugin._isRunning(), false);
@@ -178,6 +179,11 @@ test('filters out hashed files', function(t) {
   });
   const compilation = {
     assets: {
+      'c.js': {
+        emitted: true,
+        size: () => 1,
+        source: () => "asdf",
+      },
       'b.js': {
         emitted: true,
         size: () => 1,
@@ -192,12 +198,46 @@ test('filters out hashed files', function(t) {
     children: []
   };
   plugin.sourceHashs = {
-    'b.js': 'Wrong hash',
-    'a.js': hashCode('asdf'),
+    'b.js': {hash: 'Wrong hash'},
+    'a.js': {hash: hashCode('asdf')},
   };
   plugin.server = {
     notifyClients: function(files) {
-      t.deepEqual(files.sort(), ['b.js']);
+      t.deepEqual(files.sort(), ['b.js', 'c.js']);
+      t.end();
+    }
+  };
+  plugin._afterEmit(compilation);
+});
+
+test('filters out resized files', function(t) {
+  const plugin = new LiveReloadPlugin({
+    useSourceSize: true,
+  });
+  const compilation = {
+    assets: {
+      'c.js': {
+        emitted: true,
+        size: () => 10,
+      },
+      'b.js': {
+        emitted: true,
+        size: () => 10,
+      },
+      'a.js': {
+        emitted: true,
+        size: () => 20,
+      },
+    },
+    children: []
+  };
+  plugin.sourceSizes = {
+    'b.js': 20,
+    'a.js': 20,
+  };
+  plugin.server = {
+    notifyClients: function(files) {
+      t.deepEqual(files.sort(), ['b.js', 'c.js']);
       t.end();
     }
   };
@@ -275,4 +315,4 @@ test('autoloadJs suffixes empty protocol without colon', function(t) {
   const [,src] = plugin._autoloadJs().match(/src\s+=\s+"(.+)"/)
   t.assert(src.startsWith('//'));
   t.end();
-});
+});