Add test for missing defaults modules with AllowMissingDependencies

Test: defaults_test.go
Change-Id: Ic71892c379f8850996ea4dd94f606f4e937591df
diff --git a/android/defaults_test.go b/android/defaults_test.go
new file mode 100644
index 0000000..fa26595
--- /dev/null
+++ b/android/defaults_test.go
@@ -0,0 +1,116 @@
+// Copyright 2019 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package android
+
+import (
+	"testing"
+
+	"github.com/google/blueprint/proptools"
+)
+
+type defaultsTestProperties struct {
+	Foo []string
+}
+
+type defaultsTestModule struct {
+	ModuleBase
+	DefaultableModuleBase
+	properties defaultsTestProperties
+}
+
+func (d *defaultsTestModule) GenerateAndroidBuildActions(ctx ModuleContext) {
+	ctx.Build(pctx, BuildParams{
+		Rule:   Touch,
+		Output: PathForModuleOut(ctx, "out"),
+	})
+}
+
+func defaultsTestModuleFactory() Module {
+	module := &defaultsTestModule{}
+	module.AddProperties(&module.properties)
+	InitDefaultableModule(module)
+	InitAndroidModule(module)
+	return module
+}
+
+type defaultsTestDefaults struct {
+	ModuleBase
+	DefaultsModuleBase
+}
+
+func defaultsTestDefaultsFactory() Module {
+	defaults := &defaultsTestDefaults{}
+	defaults.AddProperties(&defaultsTestProperties{})
+	InitDefaultsModule(defaults)
+	return defaults
+}
+
+func TestDefaultsAllowMissingDependencies(t *testing.T) {
+	config := TestConfig(buildDir, nil)
+	config.TestProductVariables.Allow_missing_dependencies = proptools.BoolPtr(true)
+
+	ctx := NewTestContext()
+	ctx.SetAllowMissingDependencies(true)
+
+	ctx.RegisterModuleType("test", ModuleFactoryAdaptor(defaultsTestModuleFactory))
+	ctx.RegisterModuleType("defaults", ModuleFactoryAdaptor(defaultsTestDefaultsFactory))
+
+	ctx.PreArchMutators(RegisterDefaultsPreArchMutators)
+
+	ctx.Register()
+
+	bp := `
+		defaults {
+			name: "defaults",
+			defaults: ["missing"],
+			foo: ["defaults"],
+		}
+
+		test {
+			name: "missing_defaults",
+			defaults: ["missing"],
+			foo: ["module"],
+		}
+
+		test {
+			name: "missing_transitive_defaults",
+			defaults: ["defaults"],
+			foo: ["module"],
+		}
+	`
+
+	ctx.MockFileSystem(map[string][]byte{
+		"Android.bp": []byte(bp),
+	})
+
+	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
+	FailIfErrored(t, errs)
+	_, errs = ctx.PrepareBuildActions(config)
+	FailIfErrored(t, errs)
+
+	missingDefaults := ctx.ModuleForTests("missing_defaults", "").Output("out")
+	missingTransitiveDefaults := ctx.ModuleForTests("missing_transitive_defaults", "").Output("out")
+
+	if missingDefaults.Rule != ErrorRule {
+		t.Errorf("expected missing_defaults rule to be ErrorRule, got %#v", missingDefaults.Rule)
+	}
+
+	if g, w := missingDefaults.Args["error"], "module missing_defaults missing dependencies: missing\n"; g != w {
+		t.Errorf("want error %q, got %q", w, g)
+	}
+
+	// TODO: missing transitive defaults is currently not handled
+	_ = missingTransitiveDefaults
+}