Add ability to pass in locals as a function

README.md

@@ -101,14 +101,34 @@ Note that this will still be executed for each entry in your `paths` array in yo
 // The path currently being rendered:
 locals.path;
 
-// An object containing all assets:
-locals.assets;
-
 // Advanced: Webpack's stats object:
 locals.webpackStats;
 ```
 
-Any additional locals provided in your config are also available.
+## Custom locals
+
+To customise the locals provided to your render function you can use the `locals` option.
+A function passed to this option will be called before each render.
+The result will be used when rendering.
+
+```js
+const template = ejs.compile(templateSource);
+
+module.exports = {
+
+  ...
+
+  plugins: [
+    new StaticSiteGeneratorPlugin({
+      locals: ({ path, webpackStats }) => {
+        template,
+        path,
+        webpackStats
+      }
+    })
+  ]
+}
+```
 
 ## Crawl mode
 

index.js

@@ -5,16 +5,20 @@ var cheerio = require('cheerio');
 var url = require('url');
 var Promise = require('bluebird');
 
+function defaultLocalsTransform(locals) {
+  return locals;
+}
+
 function StaticSiteGeneratorWebpackPlugin(options) {
   if (arguments.length > 1) {
     options = legacyArgsToOptions.apply(null, arguments);
   }
 
-  options = options || {};
+  options = normalizeOptions(options);
 
   this.entry = options.entry;
   this.paths = Array.isArray(options.paths) ? options.paths : [options.paths || '/'];
-  this.locals = options.locals;
+  this.locals = options.locals || defaultLocalsTransform;
   this.globals = options.globals;
   this.crawl = Boolean(options.crawl);
 }
@@ -59,19 +63,13 @@ StaticSiteGeneratorWebpackPlugin.prototype.apply = function(compiler) {
   });
 };
 
-function renderPaths(crawl, userLocals, paths, render, assets, webpackStats, compilation) {
+function renderPaths(crawl, transformLocals, paths, render, assets, webpackStats, compilation) {
   var renderPromises = paths.map(function(outputPath) {
-    var locals = {
+    var locals = transformLocals({
       path: outputPath,
       assets: assets,
       webpackStats: webpackStats
-    };
-
-    for (var prop in userLocals) {
-      if (userLocals.hasOwnProperty(prop)) {
-        locals[prop] = userLocals[prop];
-      }
-    }
+    });
 
     var renderPromise = render.length < 2 ?
       Promise.resolve(render(locals)) :
@@ -97,7 +95,7 @@ function renderPaths(crawl, userLocals, paths, render, assets, webpackStats, com
               path: key
             });
 
-            return renderPaths(crawl, userLocals, relativePaths, render, assets, webpackStats, compilation);
+            return renderPaths(crawl, transformLocals, relativePaths, render, assets, webpackStats, compilation);
           }
         });
 
@@ -219,6 +217,25 @@ function relativePathsFromHtml(options) {
     });
 }
 
+function normalizeOptions(legacyOptions) {
+  var options = Object.assign({}, legacyOptions);
+
+  if (options.locals && typeof options.locals !== 'function') {
+    var userLocals = options.locals;
+    options.locals = (defaultLocals) => {
+      return Object.assign(
+        {
+          webpackStats: defaultLocals.webpackStats,
+          path: defaultLocals.path,
+          assets: defaultLocals.assets
+        },
+        userLocals
+      );
+    };
+  }
+  return options;
+}
+
 function legacyArgsToOptions(entry, paths, locals, globals) {
   return {
     entry: entry,

test/__snapshots__/index.spec.js.snap

@@ -436,3 +436,11 @@ Object {
   "index.js": "CONTENTS IGNORED IN SNAPSHOT TEST",
 }
 `;
+
+exports[`Success cases transform-locals should generate the expected files 1`] = `
+Object {
+  "bar.js": "CONTENTS IGNORED IN SNAPSHOT TEST",
+  "index.html": "<div>/foo/bar.js<br />/foo/main.js</div>",
+  "main.js": "CONTENTS IGNORED IN SNAPSHOT TEST",
+}
+`;

test/index.spec.js

@@ -6,7 +6,7 @@ const webpack = promisify(require('webpack'));
 const rimrafAsync = promisify(require('rimraf'));
 const getSubDirsSync = require('./utils/get-sub-dirs-sync');
 const dirContentsToObject = require('./utils/dir-contents-to-object');
-const directoryContains = require('./utils/directory-contains');
+const directoryContains = require('./utils/directory-contains-html');
 
 const successCases = getSubDirsSync(__dirname + '/success-cases');
 const errorCases = getSubDirsSync(__dirname + '/error-cases');

test/success-cases/transform-locals/bar.js

@@ -0,0 +1 @@
+module.exports = 'Foo';

test/success-cases/transform-locals/index.js

@@ -0,0 +1,3 @@
+module.exports = function(locals) {
+  return '<div>' + locals.chunks.join('<br />') + '</div>';
+};

test/success-cases/transform-locals/webpack.config.js

@@ -0,0 +1,30 @@
+var StaticSiteGeneratorPlugin = require('../../../');
+var ejs = require('ejs');
+var fs = require('fs');
+
+var paths = ['/', '/foo', '/foo/bar'];
+
+module.exports = {
+  entry: {
+    bar: __dirname + '/bar.js',
+    main: __dirname + '/index.js'
+  },
+
+  output: {
+    filename: '[name].js',
+    path: __dirname + '/actual-output',
+    publicPath: '/foo/',
+    libraryTarget: 'umd'
+  },
+
+  plugins: [
+    new StaticSiteGeneratorPlugin({
+      entry: 'main',
+      locals: ({ path, webpackStats }) => ({
+        chunks: Object.keys(webpackStats.compilation.assets).map(
+          file => `${webpackStats.compilation.outputOptions.publicPath}${file}`
+        )
+      })
+    })
+  ]
+};

test/utils/directory-contains.js → test/utils/directory-contains-html.js

@@ -21,7 +21,7 @@ module.exports = function(referenceDir, targetDir, done) {
     });
   };
 
-  glob('**/*', { cwd: referenceDir, nodir: true }, function(err, files) {
+  glob('**/*.html', { cwd: referenceDir, nodir: true }, function(err, files) {
     if (err) {
       return done(err);
     }