Share runBp2BuildTestCase & runPythonTestCase

Pull along bp2buildTestCase as well
Because none are specific to their current hosts

Move `errored` up to the "generic" block vs.
the "custom" block

Test: Existing tests pass
Change-Id: Ie8d5322a5554ebd88f0c142a4c541791687be326
diff --git a/bp2build/testing.go b/bp2build/testing.go
index 266b817..d8e572d 100644
--- a/bp2build/testing.go
+++ b/bp2build/testing.go
@@ -1,6 +1,7 @@
 package bp2build
 
 import (
+	"strings"
 	"testing"
 
 	"android/soong/android"
@@ -16,6 +17,86 @@
 	buildDir string
 )
 
+func errored(t *testing.T, desc string, errs []error) bool {
+	t.Helper()
+	if len(errs) > 0 {
+		for _, err := range errs {
+			t.Errorf("%s: %s", desc, err)
+		}
+		return true
+	}
+	return false
+}
+
+func runPythonTestCase(t *testing.T, tc bp2buildTestCase) {
+	t.Helper()
+	runBp2BuildTestCase(t, func(ctx android.RegistrationContext) {}, tc)
+}
+
+type bp2buildTestCase struct {
+	description                        string
+	moduleTypeUnderTest                string
+	moduleTypeUnderTestFactory         android.ModuleFactory
+	moduleTypeUnderTestBp2BuildMutator func(android.TopDownMutatorContext)
+	blueprint                          string
+	expectedBazelTargets               []string
+	filesystem                         map[string]string
+	dir                                string
+}
+
+func runBp2BuildTestCase(t *testing.T, registerModuleTypes func(ctx android.RegistrationContext), tc bp2buildTestCase) {
+	t.Helper()
+	dir := "."
+	filesystem := make(map[string][]byte)
+	toParse := []string{
+		"Android.bp",
+	}
+	for f, content := range tc.filesystem {
+		if strings.HasSuffix(f, "Android.bp") {
+			toParse = append(toParse, f)
+		}
+		filesystem[f] = []byte(content)
+	}
+	config := android.TestConfig(buildDir, nil, tc.blueprint, filesystem)
+	ctx := android.NewTestContext(config)
+
+	registerModuleTypes(ctx)
+	ctx.RegisterModuleType(tc.moduleTypeUnderTest, tc.moduleTypeUnderTestFactory)
+	ctx.RegisterBp2BuildConfig(bp2buildConfig)
+	ctx.RegisterBp2BuildMutator(tc.moduleTypeUnderTest, tc.moduleTypeUnderTestBp2BuildMutator)
+	ctx.RegisterForBazelConversion()
+
+	_, errs := ctx.ParseFileList(dir, toParse)
+	if errored(t, tc.description, errs) {
+		return
+	}
+	_, errs = ctx.ResolveDependencies(config)
+	if errored(t, tc.description, errs) {
+		return
+	}
+
+	checkDir := dir
+	if tc.dir != "" {
+		checkDir = tc.dir
+	}
+	codegenCtx := NewCodegenContext(config, *ctx.Context, Bp2Build)
+	bazelTargets := generateBazelTargetsForDir(codegenCtx, checkDir)
+	if actualCount, expectedCount := len(bazelTargets), len(tc.expectedBazelTargets); actualCount != expectedCount {
+		t.Errorf("%s: Expected %d bazel target, got %d", tc.description, expectedCount, actualCount)
+	} else {
+		for i, target := range bazelTargets {
+			if w, g := tc.expectedBazelTargets[i], target.content; w != g {
+				t.Errorf(
+					"%s: Expected generated Bazel target to be '%s', got '%s'",
+					tc.description,
+					w,
+					g,
+				)
+			}
+		}
+	}
+}
+
 type nestedProps struct {
 	Nested_prop string
 }
@@ -44,17 +125,6 @@
 	props customProps
 }
 
-func errored(t *testing.T, desc string, errs []error) bool {
-	t.Helper()
-	if len(errs) > 0 {
-		for _, err := range errs {
-			t.Errorf("%s: %s", desc, err)
-		}
-		return true
-	}
-	return false
-}
-
 // OutputFiles is needed because some instances of this module use dist with a
 // tag property which requires the module implements OutputFileProducer.
 func (m *customModule) OutputFiles(tag string) (android.Paths, error) {