Validate that the homepage is using an approved scheme.

Also cleaned up the pubspec tests a bit.

Review URL: https://codereview.chromium.org//11412017

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@14984 260f80e4-7a28-3924-810f-c04153c831b5

lib/src/pubspec.dart

@@ -76,12 +76,28 @@ class Pubspec {
     // Even though the pub app itself doesn't use these fields, we validate
     // them here so that users find errors early before they try to upload to
     // the server:
+    // TODO(rnystrom): We should split this validation into separate layers:
+    // 1. Stuff that is required in any pubspec to perform any command. Things
+    //    like "must have a name". That should go here.
+    // 2. Stuff that is required to upload a package. Things like "homepage
+    //    must use a valid scheme". That should go elsewhere. pub upload should
+    //    call it, and we should provide a separate command to show the user,
+    //    and also expose it to the editor in some way.
+
+    if (parsedPubspec.containsKey('homepage')) {
+      var homepage = parsedPubspec['homepage'];
+
+      if (homepage is! String) {
+        throw new FormatException(
+            'The "homepage" field should be a string, but was "$homepage".');
+      }
 
-    if (parsedPubspec.containsKey('homepage') &&
-        parsedPubspec['homepage'] is! String) {
-      throw new FormatException(
-          'The "homepage" field should be a string, but was '
-          '${parsedPubspec["homepage"]}.');
+      var goodScheme = new RegExp(r'^https?:');
+      if (!goodScheme.hasMatch(homepage)) {
+        throw new FormatException(
+            'The "homepage" field should be an "http:" or "https:" URL, but '
+            'was "$homepage".');
+      }
     }
 
     if (parsedPubspec.containsKey('author') &&

test/pubspec_test.dart

@@ -26,6 +26,11 @@ main() {
       var sources = new SourceRegistry();
       sources.register(new MockSource());
 
+      expectFormatError(String pubspec) {
+        expect(() => new Pubspec.parse(pubspec, sources),
+            throwsFormatException);
+      }
+
       test("allows a version constraint for dependencies", () {
         var pubspec = new Pubspec.parse('''
 dependencies:
@@ -50,55 +55,51 @@ dependencies:
       });
 
       test("throws if the description isn't valid", () {
-        expect(() {
-          new Pubspec.parse('''
+        expectFormatError('''
 dependencies:
   foo:
     mock: bad
-''', sources);
-        }, throwsFormatException);
+''');
       });
 
       test("throws if 'name' is not a string", () {
-        expect(() => new Pubspec.parse('name: [not, a, string]', sources),
-            throwsFormatException);
+        expectFormatError('name: [not, a, string]');
       });
 
       test("throws if 'homepage' is not a string", () {
-        expect(() => new Pubspec.parse('homepage: [not, a, string]', sources),
-            throwsFormatException);
+        expectFormatError('homepage:');
+        expectFormatError('homepage: [not, a, string]');
+      });
+
+      test("throws if 'homepage' doesn't have an HTTP scheme", () {
+        new Pubspec.parse('homepage: http://ok.com', sources);
+        new Pubspec.parse('homepage: https://also-ok.com', sources);
+
+        expectFormatError('ftp://badscheme.com');
+        expectFormatError('javascript:alert("!!!")');
+        expectFormatError('data:image/png;base64,somedata');
+        expectFormatError('homepage: no-scheme.com');
       });
 
       test("throws if 'authors' is not a string or a list of strings", () {
         new Pubspec.parse('authors: ok fine', sources);
         new Pubspec.parse('authors: [also, ok, fine]', sources);
 
-        expect(() => new Pubspec.parse('authors: 123', sources),
-            throwsFormatException);
-
-        expect(() => new Pubspec.parse('authors: {not: {a: string}}', sources),
-            throwsFormatException);
-
-        expect(() => new Pubspec.parse('authors: [ok, {not: ok}]', sources),
-            throwsFormatException);
+        expectFormatError('authors: 123');
+        expectFormatError('authors: {not: {a: string}}');
+        expectFormatError('authors: [ok, {not: ok}]');
       });
 
       test("throws if 'author' is not a string", () {
         new Pubspec.parse('author: ok fine', sources);
 
-        expect(() => new Pubspec.parse('author: 123', sources),
-            throwsFormatException);
-
-        expect(() => new Pubspec.parse('author: {not: {a: string}}', sources),
-            throwsFormatException);
-
-        expect(() => new Pubspec.parse('author: [not, ok]', sources),
-            throwsFormatException);
+        expectFormatError('author: 123');
+        expectFormatError('author: {not: {a: string}}');
+        expectFormatError('author: [not, ok]');
       });
 
       test("throws if both 'author' and 'authors' are present", () {
-        expect(() => new Pubspec.parse('{author: abe, authors: ted}', sources),
-            throwsFormatException);
+        expectFormatError('{author: abe, authors: ted}');
       });
 
       test("allows comment-only files", () {