feat: beforeEmit hook, add hook documentation

README.md

@@ -44,15 +44,15 @@ _Note: We recommend using [webpack-nano](https://github.com/shellscape/webpack-n
 Create a `webpack.config.js` file:
 
 ```js
-const Manifest = require('webpack-manifest-plugin');
+const { WebpackManifestPlugin } = require('webpack-manifest-plugin');
 const options = { ... };
 
 module.exports = {
 	// an example entry definition
 	entry: [ 'app.js'	],
   ...
   plugins: [
-    new Manifest(options)
+    new WebpackManifestPlugin(options)
   ]
 };
 ```
@@ -200,6 +200,31 @@ Type: `Boolean`
 
 Is required by a module. Cannot be `true` if `isAsset` is `false`.
 
+## Compiler Hooks
+
+This plugin supports the following hooks via the `getCompilerHooks` export; `afterEmit`, `beforeEmit`. These hooks can be useful, e.g. changing manifest contents before emitting to disk.
+
+### `getCompilerHooks`
+
+Returns: `{ afterEmit: SyncWaterfallHook, beforeEmit: AsyncSeriesWaterfallHook }`
+
+#### Usage
+
+```js
+const { getCompilerHooks } = require('webpack-manifest-plugin');
+
+class BatmanPlugin {
+  apply(compiler) {
+    const { beforeEmit } = getCompilerHooks();
+
+    beforeEmit.tapAsync('MyPlugin', (manifest, cb) => {
+      cb(null, { ...manifest, name: 'hello' })
+    })
+  }
+}
+
+```
+
 ## Attiribution
 
 Special thanks to [Dane Thurber](https://github.com/danethurber), the original author of this plugin, without whom this plugin would not exist.

lib/hooks.js

@@ -1,7 +1,7 @@
 const { mkdirSync, writeFileSync } = require('fs');
 const { basename, dirname, join } = require('path');
 
-const { SyncWaterfallHook } = require('tapable');
+const { AsyncSeriesWaterfallHook, SyncWaterfallHook } = require('tapable');
 
 const { generateManifest, reduceAssets, reduceChunk, transformFiles } = require('./helpers');
 
@@ -11,7 +11,8 @@ const getCompilerHooks = (compiler) => {
   let hooks = compilerHookMap.get(compiler);
   if (typeof hooks === 'undefined') {
     hooks = {
-      afterEmit: new SyncWaterfallHook(['manifest'])
+      afterEmit: new SyncWaterfallHook(['manifest']),
+      beforeEmit: new AsyncSeriesWaterfallHook(['manifest'])
     };
     compilerHookMap.set(compiler, hooks);
   }

test/unit/index.js

@@ -13,6 +13,11 @@ test.after(() => del(outputPath));
 test('exports', async (t) => {
   t.truthy(getCompilerHooks);
   t.truthy(WebpackManifestPlugin);
+
+  const compiler = {};
+  const hooks = getCompilerHooks(compiler);
+  t.snapshot(Object.keys(hooks));
+  t.is(hooks, getCompilerHooks(compiler));
 });
 
 test('outputs a manifest of one file', async (t) => {

test/unit/snapshots/index.js.md

@@ -0,0 +1,14 @@
+# Snapshot report for `test/unit/index.js`
+
+The actual snapshot is saved in `index.js.snap`.
+
+Generated by [AVA](https://avajs.dev).
+
+## exports
+
+> Snapshot 1
+
+    [
+      'afterEmit',
+      'beforeEmit',
+    ]