Clean up barback tests.

pkg/barback/test/asset_graph/source_test.dart

Index: pkg/barback/test/asset_graph/source_test.dart
diff --git a/pkg/barback/test/asset_graph/source_test.dart b/pkg/barback/test/asset_graph/source_test.dart
index 32d7f3d0f0f3696f68e0c092639b1b3f1b39ebb9..8227edbb2f3a27f26dcd5bbc2fa1f8367df2c280 100644
--- a/pkg/barback/test/asset_graph/source_test.dart
+++ b/pkg/barback/test/asset_graph/source_test.dart
@@ -15,31 +15,24 @@ import '../utils.dart';
 main() {
   initConfig();
   test("gets a source asset", () {
-    var provider = new MockProvider(["app|foo.txt"]);
-    var graph = new AssetGraph(provider, []);
-    graph.updateSources([new AssetId.parse("app|foo.txt")]);
-
-    expectAsset(graph, "app|foo.txt");
+    initGraph(["app|foo.txt"]);
+    updateSources(["app|foo.txt"]);
+    expectAsset("app|foo.txt");
   });
 
   test("doesn't get an unknown source", () {
-    var provider = new MockProvider([]);
-    var graph = new AssetGraph(provider, []);
-
-    expectNoAsset(graph, "app|unknown.txt");
+    initGraph();
+    expectNoAsset("app|unknown.txt");
   });
 
   test("doesn't get an unprovided source", () {
-    var provider = new MockProvider([]);
-    var graph = new AssetGraph(provider, []);
-
-    graph.updateSources([new AssetId.parse("app|unknown.txt")]);
-    expectNoAsset(graph, "app|unknown.txt");
+    initGraph();
+    updateSources(["app|unknown.txt"]);
+    expectNoAsset("app|unknown.txt");
   });
 
   test("doesn't get an asset that isn't an updated source", () {
-    var provider = new MockProvider(["app|foo.txt"]);
-    var graph = new AssetGraph(provider, []);
+    initGraph(["app|foo.txt"]);
 
     // Sources must be explicitly made visible to barback by calling
     // updateSources() on them. It isn't enough for the provider to be able
@@ -47,47 +40,44 @@ main() {
     //
     // This lets you distinguish between sources that you want to be primaries
     // and the larger set of inputs that those primaries are allowed to pull in.
-    expectNoAsset(graph, "app|foo.txt");
+    expectNoAsset("app|foo.txt");
   });
 
   test("gets a source asset if not transformed", () {
-    var provider = new MockProvider(["app|foo.txt"]);
-    var graph = new AssetGraph(provider, [
+    initGraph(["app|foo.txt"], [
       [new RewriteTransformer("nottxt", "whatever")]
     ]);
-    graph.updateSources([new AssetId.parse("app|foo.txt")]);
 
-    expectAsset(graph, "app|foo.txt");
+    updateSources(["app|foo.txt"]);
+    expectAsset("app|foo.txt");
   });
 
   test("doesn't get a removed source", () {
-    var provider = new MockProvider(["app|foo.txt"]);
-    var graph = new AssetGraph(provider, [[]]);
-    graph.updateSources([new AssetId.parse("app|foo.txt")]);
+    initGraph(["app|foo.txt"]);
 
-    expectAsset(graph, "app|foo.txt");
+    updateSources(["app|foo.txt"]);
+    expectAsset("app|foo.txt");
 
     schedule(() {
-      graph.removeSources([new AssetId.parse("app|foo.txt")]);
+      removeSources(["app|foo.txt"]);
     });
 
-    expectNoAsset(graph, "app|foo.txt");
+    expectNoAsset("app|foo.txt");
   });
 
   test("collapses redundant updates", () {
-    var provider = new MockProvider(["app|foo.blub"]);
     var transformer = new RewriteTransformer("blub", "blab");
-    var graph = new AssetGraph(provider, [[transformer]]);
+    initGraph(["app|foo.blub"], [[transformer]]);
 
     schedule(() {
       // Make a bunch of synchronous update calls.
-      graph.updateSources([new AssetId.parse("app|foo.blub")]);
-      graph.updateSources([new AssetId.parse("app|foo.blub")]);
-      graph.updateSources([new AssetId.parse("app|foo.blub")]);
-      graph.updateSources([new AssetId.parse("app|foo.blub")]);
+      updateSources(["app|foo.blub"]);
+      updateSources(["app|foo.blub"]);
+      updateSources(["app|foo.blub"]);
+      updateSources(["app|foo.blub"]);
     });
 
-    expectAsset(graph, "app|foo.blab", "foo.blab");
+    expectAsset("app|foo.blab", "foo.blab");
 
     schedule(() {
       expect(transformer.numRuns, equals(1));
@@ -95,73 +85,55 @@ main() {
   });
 
   test("a removal cancels out an update", () {
-    var provider = new MockProvider(["app|foo.txt"]);
-    var graph = new AssetGraph(provider, [[]]);
+    initGraph(["app|foo.txt"]);
 
     schedule(() {
-      graph.updateSources([new AssetId.parse("app|foo.txt")]);
-      graph.removeSources([new AssetId.parse("app|foo.txt")]);
+      updateSources(["app|foo.txt"]);
+      removeSources(["app|foo.txt"]);
     });
 
-    expectNoAsset(graph, "app|foo.txt");
+    expectNoAsset("app|foo.txt");
   });
 
   test("an update cancels out a removal", () {
-    var provider = new MockProvider(["app|foo.txt"]);
-    var graph = new AssetGraph(provider, [[]]);
+    initGraph(["app|foo.txt"]);
 
     schedule(() {
-      graph.removeSources([new AssetId.parse("app|foo.txt")]);
-      graph.updateSources([new AssetId.parse("app|foo.txt")]);
+      removeSources(["app|foo.txt"]);
+      updateSources(["app|foo.txt"]);
     });
 
-    expectAsset(graph, "app|foo.txt");
+    expectAsset("app|foo.txt");
   });
 
   test("restarts a build if a source is updated while sources are loading", () {
-    var provider = new MockProvider(["app|foo.txt", "app|other.bar"]);
     var transformer = new RewriteTransformer("txt", "out");
-    var graph = new AssetGraph(provider, [[transformer]]);
+    initGraph(["app|foo.txt", "app|other.bar"], [[transformer]]);
 
-    var numBuilds = 0;
-    var buildCompleter = new Completer();
-    graph.results.listen(wrapAsync((result) {
-      expect(result.error, isNull);
-      numBuilds++;
+    // Run the whole graph so all nodes are clean.
+    updateSources(["app|foo.txt", "app|other.bar"]);
+    expectAsset("app|foo.out", "foo.out");
+    expectAsset("app|other.bar");
 
-      // There should be two builds, one for each update call.
-      if (numBuilds == 2) buildCompleter.complete();
-    }));
+    buildShouldSucceed();
 
-    // Run the whole graph so all nodes are clean.
-    graph.updateSources([
-      new AssetId.parse("app|foo.txt"),
-      new AssetId.parse("app|other.bar")
-    ]);
-    expectAsset(graph, "app|foo.out", "foo.out");
-    expectAsset(graph, "app|other.bar");
+    // Make the provider slow to load a source.
+    pauseProvider();
 
     schedule(() {
-      // Make the provider slow to load a source.
-      provider.wait();
-
       // Update an asset that doesn't trigger any transformers.
-      graph.updateSources([new AssetId.parse("app|other.bar")]);
+      updateSources(["app|other.bar"]);
     });
 
     schedule(() {
       // Now update an asset that does trigger a transformer.
-      graph.updateSources([new AssetId.parse("app|foo.txt")]);
+      updateSources(["app|foo.txt"]);
     });
 
-    schedule(() {
-      provider.complete();
-    });
+    resumeProvider();
 
-    schedule(() {
-      // Wait until the build has completed.
-      return buildCompleter.future;
-    });
+    buildShouldSucceed();
+    waitForBuild();
 
     schedule(() {
       expect(transformer.numRuns, equals(2));