Avoid extra assignment for default export

Makefile

@@ -302,13 +302,9 @@ build/test_rendering_requires.js: $(SPEC_RENDERING_JS)
 %shader.js: %shader.glsl src/ol/webgl/shader.mustache bin/pyglslunit.py build/timestamps/node-modules-timestamp
 	@python bin/pyglslunit.py --input $< | ./node_modules/.bin/mustache - src/ol/webgl/shader.mustache > $@
 
-build/defines.json: src/ol/index.js build/timestamps/node-modules-timestamp
-	@node tasks/generate-defines.js
-
 .PHONY: package
-package: build/defines.json
+package:
 	@rm -rf build/package
-	@node tasks/generate-defines.js
 	@cp -r package build
 	@cd ./src && cp -r ol/* ../build/package
 	@rm build/package/typedefs.js

package/package.json

@@ -1,7 +1,7 @@
 {
   "name": "ol",
-  "version": "3.21.0-beta.10",
+  "version": "3.21.0-beta.16",
-  "description": "OpenLayers",
+  "description": "OpenLayers as ES2015 modules",
   "main": "index.js",
   "module": "index.js",
   "license": "BSD-2-Clause",

package/readme.md

@@ -1,6 +1,6 @@
-# `ol`
+# ol
 
-[OpenLayers](https://openlayers.org/) for module loaders.
+OpenLayers as ES2015 modules.
 
 **Note: This is still a work in progress.  Not yet ready for production.**
 
@@ -13,16 +13,18 @@ Add the `ol` package as a dependency to your project.
 Import just what you need for your application:
 
 ```js
-import Map from 'ol/Map';
+import Map from 'ol/map';
-import View from 'ol/View';
+import View from 'ol/view';
-import TileLayer from 'ol/layer/Tile';
+import TileLayer from 'ol/layer/tile';
-import OSM from 'ol/source/OSM';
+import XYZ from 'ol/source/xyz';
 
-var map = new Map({
+new Map({
   target: 'map',
   layers: [
     new TileLayer({
-      source: new OSM()
+      source: new XYZ({
+        url: 'https://{a-c}.tile.openstreetmap.org/{z}/{x}/{y}.png'
+      })
     })
   ],
   view: new View({
@@ -31,3 +33,14 @@ var map = new Map({
   })
 });
 ```
+
+Note that the module identifiers above (e.g. `ol/map`) are like the `ol.Map` names in the [API documentation](http://openlayers.org/en/latest/apidoc/) with `/` instead of `.` and all lowercase.
+
+See the following examples for more detail on bundling OpenLayers with your application:
+
+ * Using [Rollup & Uglify](https://gist.github.com/tschaub/8beb328ea72b36446fc2198d008287de)
+ * Using [Rollup & Closure Compiler](https://gist.github.com/tschaub/32a5692bedac5254da24fa3b12072f35)
+ * Using [Webpack & Uglify](https://gist.github.com/tschaub/79025aef325cd2837364400a105405b8)
+ * Using [Browserify & Uglify](https://gist.github.com/tschaub/4bfb209a8f809823f1495b2e4436018e)
+
+This is still a work in progress.  See [openlayers/openlayers#6302](https://github.com/openlayers/openlayers/pull/6302) for ongoing discussion.

tasks/generate-defines.js

@@ -1,31 +0,0 @@
-var fs = require('fs');
-var path = require('path');
-var esprima = require('esprima');
-
-var mainPath = path.join(__dirname, '..', 'src', 'ol', 'index.js');
-var mainSource = fs.readFileSync(mainPath, 'utf8');
-var definesPath = path.join(__dirname, '..', 'build', 'defines.json');
-
-function isDefineLikeStatement(statement) {
-  return statement.type === 'ExpressionStatement' &&
-      statement.expression && statement.expression.type === 'AssignmentExpression' &&
-      statement.expression.left.type === 'MemberExpression' &&
-      statement.expression.right.type === 'Literal' &&
-      statement.leadingComments;
-}
-
-var ast = esprima.parse(mainSource, {attachComment: true});
-var defines = {};
-ast.body.forEach(function(statement) {
-  if (isDefineLikeStatement(statement)) {
-    var comment = statement.leadingComments[statement.leadingComments.length - 1].value;
-    if (comment.indexOf('* @define {') >= 0) {
-      var expression = statement.expression;
-      var name = expression.left.object.name + '.' + expression.left.property.name;
-      var value = expression.right.value;
-      defines[name] = value;
-    }
-  }
-});
-
-fs.writeFileSync(definesPath, JSON.stringify(defines, null, 2));

transforms/module.js

@@ -10,10 +10,6 @@ function rename(name) {
   return `_${parts.join('_')}_`;
 }
 
-function renameDefine(name) {
-  return name.replace('.', '_').toUpperCase();
-}
-
 function resolve(fromName, toName) {
   const fromParts = fromName.split('.');
   const toParts = toName.split('.');
@@ -106,6 +102,16 @@ function getMemberExpression(name) {
   return memberExpression(name);
 }
 
+function getMemberExpressionAssignment(name) {
+  return {
+    type: 'ExpressionStatement',
+    expression: {
+      type: 'AssignmentExpression',
+      left: getMemberExpression(name)
+    }
+  };
+}
+
 module.exports = function(info, api) {
   const j = api.jscodeshift;
   const root = j(info.source);
@@ -127,24 +133,43 @@ module.exports = function(info, api) {
       return j.literal(defines[name]);
     });
 
-  // replace goog.provide()
+  // remove goog.provide()
   let provide;
   root.find(j.ExpressionStatement, getGoogExpressionStatement('provide'))
-    .replaceWith(path => {
+    .forEach(path => {
       if (provide) {
         throw new Error(`Multiple provides in ${info.path}`);
       }
       provide = path.value.expression.arguments[0].value;
-      return j.variableDeclaration('var', [
+    }).remove();
-        j.variableDeclarator(j.identifier(rename(provide)), j.objectExpression([]))
-      ]);
-    });
 
   if (!provide) {
     throw new Error(`No provide found in ${info.path}`);
   }
   replacements[provide] = rename(provide);
 
+  // replace provide assignment with variable declarator
+  // e.g. `ol.foo.Bar = function() {}` -> `var _ol_foo_Bar_ = function() {}`
+  let declaredProvide = false;
+  root.find(j.ExpressionStatement, getMemberExpressionAssignment(provide))
+    .replaceWith(path => {
+      declaredProvide = true;
+      const statement = j.variableDeclaration('var', [
+        j.variableDeclarator(j.identifier(rename(provide)), path.value.expression.right)
+      ]);
+      statement.comments = path.value.comments;
+      return statement;
+    });
+
+  if (!declaredProvide) {
+    const body = root.find(j.Program).get('body');
+    body.unshift(
+      j.variableDeclaration('var', [
+        j.variableDeclarator(j.identifier(rename(provide)), j.objectExpression([]))
+      ])
+    );
+  }
+
   // replace `goog.require('foo')` with `import foo from 'foo'`
   const imports = [];
   root.find(j.ExpressionStatement, getGoogExpressionStatement('require'))