feat(ol): sort ol.ext entry point to the top if present

plugins/gcc/webpack-writer.js

@@ -19,6 +19,21 @@ const closureWebpackInternalProps = [
   'output_wrapper'
 ];
 
+/**
+ * Entry point for the ol.ext provide. This file fixes a compiler issue and needs to be loaded first if present.
+ * @type {string}
+ */
+const olExtEntryPoint = 'goog:ol.ext';
+
+/**
+ * Sort entry points. Brings the ol.ext entry point to the top of the list, and leaves remaining entry points in their
+ * original order.
+ * @param {string} a First entry point.
+ * @param {string} b Second entry point.
+ * @return {number} The sort order.
+ */
+const sortEntryPoints = (a, b) => a === olExtEntryPoint ? -1 : b === olExtEntryPoint ? 1 : 0;
+
 /**
  * Write support files for webpack.
  * @param {Object} basePackage The base package.
@@ -40,6 +55,7 @@ const writer = function(basePackage, dir, options) {
   if (entryPoints && entryPoints.length) {
     const entryPoints = Array.isArray(options.entry_point) ? options.entry_point : [options.entry_point];
     const indexContent = entryPoints
+      .sort(sortEntryPoints)
       .map((ep) => `goog.require('${ep.replace(/^goog:/, '')}');`)
       .join('\n');
 

test/plugins/gcc/webpack-writer.test.js

@@ -114,4 +114,20 @@ describe('gcc webpack writer', function() {
         expect(content).to.equal(expectedContent);
       });
   });
+
+  it('should sort ol.ext as the first entry point', function() {
+    var jsonOptions = {
+      entry_point: ['goog:ns1', 'goog:ol.ext', 'goog:ns2']
+    };
+
+    var expectedContent = `goog.require('ol.ext');\ngoog.require('ns1');\ngoog.require('ns2');`;
+
+    return webpack.writer(pack, outputDir, jsonOptions)
+      .then(() => {
+        return fs.readFileAsync(indexFile, 'utf-8');
+      })
+      .then((content) => {
+        expect(content).to.equal(expectedContent);
+      });
+  });
 });