diff --git a/android/androidmk_test.go b/android/androidmk_test.go
index a558f45..10527b9 100644
--- a/android/androidmk_test.go
+++ b/android/androidmk_test.go
@@ -80,10 +80,10 @@
 	config := TestConfig(buildDir, nil, bp, nil)
 	config.inMake = true // Enable androidmk Singleton
 
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 	ctx.RegisterSingletonType("androidmk", AndroidMkSingleton)
 	ctx.RegisterModuleType("custom", customModuleFactory)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
@@ -252,10 +252,10 @@
 		config := TestConfig(buildDir, nil, testCase.bp, nil)
 		config.inMake = true // Enable androidmk Singleton
 
-		ctx := NewTestContext()
+		ctx := NewTestContext(config)
 		ctx.RegisterSingletonType("androidmk", AndroidMkSingleton)
 		ctx.RegisterModuleType("custom", customModuleFactory)
-		ctx.Register(config)
+		ctx.Register()
 
 		_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 		FailIfErrored(t, errs)
diff --git a/android/arch_test.go b/android/arch_test.go
index 8525b03..4cef4c8 100644
--- a/android/arch_test.go
+++ b/android/arch_test.go
@@ -353,9 +353,9 @@
 		t.Run(tt.name, func(t *testing.T) {
 			config := TestArchConfig(buildDir, nil, bp, nil)
 
-			ctx := NewTestArchContext()
+			ctx := NewTestArchContext(config)
 			ctx.RegisterModuleType("module", archTestModuleFactory)
-			ctx.Register(config)
+			ctx.Register()
 			if tt.config != nil {
 				tt.config(config)
 			}
@@ -442,9 +442,9 @@
 		t.Run(tt.name, func(t *testing.T) {
 			config := TestArchConfigNativeBridge(buildDir, nil, bp, nil)
 
-			ctx := NewTestArchContext()
+			ctx := NewTestArchContext(config)
 			ctx.RegisterModuleType("module", archTestModuleFactory)
-			ctx.Register(config)
+			ctx.Register()
 			if tt.config != nil {
 				tt.config(config)
 			}
diff --git a/android/csuite_config_test.go b/android/csuite_config_test.go
index bf1a19a..9ac959e 100644
--- a/android/csuite_config_test.go
+++ b/android/csuite_config_test.go
@@ -21,9 +21,9 @@
 func testCSuiteConfig(test *testing.T, bpFileContents string) *TestContext {
 	config := TestArchConfig(buildDir, nil, bpFileContents, nil)
 
-	ctx := NewTestArchContext()
+	ctx := NewTestArchContext(config)
 	ctx.RegisterModuleType("csuite_config", CSuiteConfigFactory)
-	ctx.Register(config)
+	ctx.Register()
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(test, errs)
 	_, errs = ctx.PrepareBuildActions(config)
diff --git a/android/defaults_test.go b/android/defaults_test.go
index d096b2f..2689d86 100644
--- a/android/defaults_test.go
+++ b/android/defaults_test.go
@@ -80,14 +80,14 @@
 
 	config := TestConfig(buildDir, nil, bp, nil)
 
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 
 	ctx.RegisterModuleType("test", defaultsTestModuleFactory)
 	ctx.RegisterModuleType("defaults", defaultsTestDefaultsFactory)
 
 	ctx.PreArchMutators(RegisterDefaultsPreArchMutators)
 
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
@@ -125,7 +125,7 @@
 	config := TestConfig(buildDir, nil, bp, nil)
 	config.TestProductVariables.Allow_missing_dependencies = proptools.BoolPtr(true)
 
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 	ctx.SetAllowMissingDependencies(true)
 
 	ctx.RegisterModuleType("test", defaultsTestModuleFactory)
@@ -133,7 +133,7 @@
 
 	ctx.PreArchMutators(RegisterDefaultsPreArchMutators)
 
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
diff --git a/android/module_test.go b/android/module_test.go
index 3a039e2..6cc1813 100644
--- a/android/module_test.go
+++ b/android/module_test.go
@@ -164,9 +164,6 @@
 }
 
 func TestErrorDependsOnDisabledModule(t *testing.T) {
-	ctx := NewTestContext()
-	ctx.RegisterModuleType("deps", depsModuleFactory)
-
 	bp := `
 		deps {
 			name: "foo",
@@ -180,7 +177,9 @@
 
 	config := TestConfig(buildDir, nil, bp, nil)
 
-	ctx.Register(config)
+	ctx := NewTestContext(config)
+	ctx.RegisterModuleType("deps", depsModuleFactory)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
diff --git a/android/mutator_test.go b/android/mutator_test.go
index 191b535..1c395c7 100644
--- a/android/mutator_test.go
+++ b/android/mutator_test.go
@@ -70,7 +70,7 @@
 	config := TestConfig(buildDir, nil, bp, nil)
 	config.TestProductVariables.Allow_missing_dependencies = proptools.BoolPtr(true)
 
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 	ctx.SetAllowMissingDependencies(true)
 
 	ctx.RegisterModuleType("test", mutatorTestModuleFactory)
@@ -78,7 +78,7 @@
 		ctx.TopDown("add_missing_dependencies", addMissingDependenciesMutator)
 	})
 
-	ctx.Register(config)
+	ctx.Register()
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
 	_, errs = ctx.PrepareBuildActions(config)
@@ -92,7 +92,15 @@
 }
 
 func TestModuleString(t *testing.T) {
-	ctx := NewTestContext()
+	bp := `
+		test {
+			name: "foo",
+		}
+	`
+
+	config := TestConfig(buildDir, nil, bp, nil)
+
+	ctx := NewTestContext(config)
 
 	var moduleStrings []string
 
@@ -130,15 +138,7 @@
 
 	ctx.RegisterModuleType("test", mutatorTestModuleFactory)
 
-	bp := `
-		test {
-			name: "foo",
-		}
-	`
-
-	config := TestConfig(buildDir, nil, bp, nil)
-
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
@@ -190,7 +190,21 @@
 }
 
 func TestFinalDepsPhase(t *testing.T) {
-	ctx := NewTestContext()
+	bp := `
+		test {
+			name: "common_dep_1",
+		}
+		test {
+			name: "common_dep_2",
+		}
+		test {
+			name: "foo",
+		}
+	`
+
+	config := TestConfig(buildDir, nil, bp, nil)
+
+	ctx := NewTestContext(config)
 
 	finalGot := map[string]int{}
 
@@ -228,20 +242,7 @@
 
 	ctx.RegisterModuleType("test", mutatorTestModuleFactory)
 
-	bp := `
-		test {
-			name: "common_dep_1",
-		}
-		test {
-			name: "common_dep_2",
-		}
-		test {
-			name: "foo",
-		}
-	`
-
-	config := TestConfig(buildDir, nil, bp, nil)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
@@ -267,7 +268,8 @@
 }
 
 func TestNoCreateVariationsInFinalDeps(t *testing.T) {
-	ctx := NewTestContext()
+	config := TestConfig(buildDir, nil, `test {name: "foo"}`, nil)
+	ctx := NewTestContext(config)
 
 	checkErr := func() {
 		if err := recover(); err == nil || !strings.Contains(fmt.Sprintf("%s", err), "not allowed in FinalDepsMutators") {
@@ -287,8 +289,7 @@
 	})
 
 	ctx.RegisterModuleType("test", mutatorTestModuleFactory)
-	config := TestConfig(buildDir, nil, `test {name: "foo"}`, nil)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
diff --git a/android/namespace_test.go b/android/namespace_test.go
index 66c0d89..45e2cdb 100644
--- a/android/namespace_test.go
+++ b/android/namespace_test.go
@@ -635,7 +635,7 @@
 func setupTestFromFiles(bps map[string][]byte) (ctx *TestContext, errs []error) {
 	config := TestConfig(buildDir, nil, "", bps)
 
-	ctx = NewTestContext()
+	ctx = NewTestContext(config)
 	ctx.RegisterModuleType("test_module", newTestModule)
 	ctx.RegisterModuleType("soong_namespace", NamespaceFactory)
 	ctx.Context.RegisterModuleType("blueprint_test_module", newBlueprintTestModule)
@@ -643,7 +643,7 @@
 	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
 		ctx.BottomUp("rename", renameMutator)
 	})
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs = ctx.ParseBlueprintsFiles("Android.bp")
 	if len(errs) > 0 {
diff --git a/android/neverallow_test.go b/android/neverallow_test.go
index 56a07dc..1d454e5 100644
--- a/android/neverallow_test.go
+++ b/android/neverallow_test.go
@@ -359,14 +359,14 @@
 }
 
 func testNeverallow(config Config) (*TestContext, []error) {
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 	ctx.RegisterModuleType("cc_library", newMockCcLibraryModule)
 	ctx.RegisterModuleType("java_library", newMockJavaLibraryModule)
 	ctx.RegisterModuleType("java_library_host", newMockJavaLibraryModule)
 	ctx.RegisterModuleType("java_device_for_host", newMockJavaLibraryModule)
 	ctx.RegisterModuleType("makefile_goal", newMockMakefileGoalModule)
 	ctx.PostDepsMutators(RegisterNeverallowMutator)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseBlueprintsFiles("Android.bp")
 	if len(errs) > 0 {
diff --git a/android/package_test.go b/android/package_test.go
index 04dfc08..ade95d4 100644
--- a/android/package_test.go
+++ b/android/package_test.go
@@ -86,9 +86,9 @@
 	// Create a new config per test as visibility information is stored in the config.
 	config := TestArchConfig(buildDir, nil, "", fs)
 
-	ctx := NewTestArchContext()
+	ctx := NewTestArchContext(config)
 	RegisterPackageBuildComponents(ctx)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseBlueprintsFiles(".")
 	if len(errs) > 0 {
diff --git a/android/path_properties_test.go b/android/path_properties_test.go
index f367b82..f964d9f 100644
--- a/android/path_properties_test.go
+++ b/android/path_properties_test.go
@@ -116,12 +116,12 @@
 			`
 
 			config := TestArchConfig(buildDir, nil, bp, nil)
-			ctx := NewTestArchContext()
+			ctx := NewTestArchContext(config)
 
 			ctx.RegisterModuleType("test", pathDepsMutatorTestModuleFactory)
 			ctx.RegisterModuleType("filegroup", FileGroupFactory)
 
-			ctx.Register(config)
+			ctx.Register()
 			_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 			FailIfErrored(t, errs)
 			_, errs = ctx.PrepareBuildActions(config)
diff --git a/android/paths_test.go b/android/paths_test.go
index e7fd763..14a4773 100644
--- a/android/paths_test.go
+++ b/android/paths_test.go
@@ -980,12 +980,6 @@
 func testPathForModuleSrc(t *testing.T, buildDir string, tests []pathForModuleSrcTestCase) {
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
-			ctx := NewTestContext()
-
-			ctx.RegisterModuleType("test", pathForModuleSrcTestModuleFactory)
-			ctx.RegisterModuleType("output_file_provider", pathForModuleSrcOutputFileProviderModuleFactory)
-			ctx.RegisterModuleType("filegroup", FileGroupFactory)
-
 			fgBp := `
 				filegroup {
 					name: "a",
@@ -1015,7 +1009,13 @@
 
 			config := TestConfig(buildDir, nil, "", mockFS)
 
-			ctx.Register(config)
+			ctx := NewTestContext(config)
+
+			ctx.RegisterModuleType("test", pathForModuleSrcTestModuleFactory)
+			ctx.RegisterModuleType("output_file_provider", pathForModuleSrcOutputFileProviderModuleFactory)
+			ctx.RegisterModuleType("filegroup", FileGroupFactory)
+
+			ctx.Register()
 			_, errs := ctx.ParseFileList(".", []string{"fg/Android.bp", "foo/Android.bp", "ofp/Android.bp"})
 			FailIfErrored(t, errs)
 			_, errs = ctx.PrepareBuildActions(config)
@@ -1224,12 +1224,12 @@
 	config := TestConfig(buildDir, nil, bp, nil)
 	config.TestProductVariables.Allow_missing_dependencies = proptools.BoolPtr(true)
 
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 	ctx.SetAllowMissingDependencies(true)
 
 	ctx.RegisterModuleType("test", pathForModuleSrcTestModuleFactory)
 
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
diff --git a/android/prebuilt_test.go b/android/prebuilt_test.go
index 854395e..9ac3875 100644
--- a/android/prebuilt_test.go
+++ b/android/prebuilt_test.go
@@ -288,10 +288,10 @@
 				{Windows, Arch{ArchType: X86_64}, NativeBridgeDisabled, "", "", true},
 			}
 
-			ctx := NewTestArchContext()
+			ctx := NewTestArchContext(config)
 			registerTestPrebuiltBuildComponents(ctx)
 			ctx.RegisterModuleType("filegroup", FileGroupFactory)
-			ctx.Register(config)
+			ctx.Register()
 
 			_, errs := ctx.ParseBlueprintsFiles("Android.bp")
 			FailIfErrored(t, errs)
diff --git a/android/register.go b/android/register.go
index ad3df7e..bd824c9 100644
--- a/android/register.go
+++ b/android/register.go
@@ -81,10 +81,11 @@
 
 type Context struct {
 	*blueprint.Context
+	config Config
 }
 
-func NewContext() *Context {
-	ctx := &Context{blueprint.NewContext()}
+func NewContext(config Config) *Context {
+	ctx := &Context{blueprint.NewContext(), config}
 	ctx.SetSrcDir(absSrcDir)
 	return ctx
 }
@@ -157,7 +158,7 @@
 // Extracting the actual registration into a separate RegisterBuildComponents(ctx) function
 // allows it to be used to initialize test context, e.g.
 //
-//   ctx := android.NewTestContext()
+//   ctx := android.NewTestContext(config)
 //   RegisterBuildComponents(ctx)
 var InitRegistrationContext RegistrationContext = &initRegistrationContext{
 	moduleTypes:    make(map[string]ModuleFactory),
diff --git a/android/rule_builder_test.go b/android/rule_builder_test.go
index 0d1070d..ca6359d 100644
--- a/android/rule_builder_test.go
+++ b/android/rule_builder_test.go
@@ -507,10 +507,10 @@
 	`
 
 	config := TestConfig(buildDir, nil, bp, fs)
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 	ctx.RegisterModuleType("rule_builder_test", testRuleBuilderFactory)
 	ctx.RegisterSingletonType("rule_builder_test", testRuleBuilderSingletonFactory)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
diff --git a/android/soong_config_modules_test.go b/android/soong_config_modules_test.go
index 9677f34..b1810b3 100644
--- a/android/soong_config_modules_test.go
+++ b/android/soong_config_modules_test.go
@@ -175,7 +175,7 @@
 			},
 		}
 
-		ctx := NewTestContext()
+		ctx := NewTestContext(config)
 		ctx.RegisterModuleType("soong_config_module_type_import", soongConfigModuleTypeImportFactory)
 		ctx.RegisterModuleType("soong_config_module_type", soongConfigModuleTypeFactory)
 		ctx.RegisterModuleType("soong_config_string_variable", soongConfigStringVariableDummyFactory)
@@ -183,7 +183,7 @@
 		ctx.RegisterModuleType("test_defaults", soongConfigTestDefaultsModuleFactory)
 		ctx.RegisterModuleType("test", soongConfigTestModuleFactory)
 		ctx.PreArchMutators(RegisterDefaultsPreArchMutators)
-		ctx.Register(config)
+		ctx.Register()
 
 		_, errs := ctx.ParseBlueprintsFiles("Android.bp")
 		FailIfErrored(t, errs)
diff --git a/android/testing.go b/android/testing.go
index 8ea4168..d83cecc 100644
--- a/android/testing.go
+++ b/android/testing.go
@@ -25,14 +25,14 @@
 	"github.com/google/blueprint"
 )
 
-func NewTestContext() *TestContext {
+func NewTestContext(config Config) *TestContext {
 	namespaceExportFilter := func(namespace *Namespace) bool {
 		return true
 	}
 
 	nameResolver := NewNameResolver(namespaceExportFilter)
 	ctx := &TestContext{
-		Context:      &Context{blueprint.NewContext()},
+		Context:      &Context{blueprint.NewContext(), config},
 		NameResolver: nameResolver,
 	}
 
@@ -40,11 +40,16 @@
 
 	ctx.postDeps = append(ctx.postDeps, registerPathDepsMutator)
 
+	ctx.SetFs(ctx.config.fs)
+	if ctx.config.mockBpList != "" {
+		ctx.SetModuleListFile(ctx.config.mockBpList)
+	}
+
 	return ctx
 }
 
-func NewTestArchContext() *TestContext {
-	ctx := NewTestContext()
+func NewTestArchContext(config Config) *TestContext {
+	ctx := NewTestContext(config)
 	ctx.preDeps = append(ctx.preDeps, registerArchMutator)
 	return ctx
 }
@@ -53,7 +58,6 @@
 	*Context
 	preArch, preDeps, postDeps, finalDeps []RegisterMutatorFunc
 	NameResolver                          *NameResolver
-	config                                Config
 }
 
 func (ctx *TestContext) PreArchMutators(f RegisterMutatorFunc) {
@@ -77,16 +81,10 @@
 	ctx.finalDeps = append(ctx.finalDeps, f)
 }
 
-func (ctx *TestContext) Register(config Config) {
-	ctx.SetFs(config.fs)
-	if config.mockBpList != "" {
-		ctx.SetModuleListFile(config.mockBpList)
-	}
+func (ctx *TestContext) Register() {
 	registerMutators(ctx.Context.Context, ctx.preArch, ctx.preDeps, ctx.postDeps, ctx.finalDeps)
 
 	ctx.RegisterSingletonType("env", EnvSingleton)
-
-	ctx.config = config
 }
 
 func (ctx *TestContext) ParseFileList(rootDir string, filePaths []string) (deps []string, errs []error) {
diff --git a/android/variable_test.go b/android/variable_test.go
index 9cafedd..393fe01 100644
--- a/android/variable_test.go
+++ b/android/variable_test.go
@@ -157,23 +157,6 @@
 }
 
 func TestProductVariables(t *testing.T) {
-	ctx := NewTestContext()
-	// A module type that has a srcs property but not a cflags property.
-	ctx.RegisterModuleType("module1", testProductVariableModuleFactoryFactory(&struct {
-		Srcs []string
-	}{}))
-	// A module type that has a cflags property but not a srcs property.
-	ctx.RegisterModuleType("module2", testProductVariableModuleFactoryFactory(&struct {
-		Cflags []string
-	}{}))
-	// A module type that does not have any properties that match product_variables.
-	ctx.RegisterModuleType("module3", testProductVariableModuleFactoryFactory(&struct {
-		Foo []string
-	}{}))
-	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
-		ctx.BottomUp("variable", VariableMutator).Parallel()
-	})
-
 	// Test that a module can use one product variable even if it doesn't have all the properties
 	// supported by that product variable.
 	bp := `
@@ -201,7 +184,24 @@
 	config := TestConfig(buildDir, nil, bp, nil)
 	config.TestProductVariables.Eng = proptools.BoolPtr(true)
 
-	ctx.Register(config)
+	ctx := NewTestContext(config)
+	// A module type that has a srcs property but not a cflags property.
+	ctx.RegisterModuleType("module1", testProductVariableModuleFactoryFactory(&struct {
+		Srcs []string
+	}{}))
+	// A module type that has a cflags property but not a srcs property.
+	ctx.RegisterModuleType("module2", testProductVariableModuleFactoryFactory(&struct {
+		Cflags []string
+	}{}))
+	// A module type that does not have any properties that match product_variables.
+	ctx.RegisterModuleType("module3", testProductVariableModuleFactoryFactory(&struct {
+		Foo []string
+	}{}))
+	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
+		ctx.BottomUp("variable", VariableMutator).Parallel()
+	})
+
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
@@ -293,7 +293,7 @@
 	config := TestConfig(buildDir, nil, bp, nil)
 	config.TestProductVariables.Eng = boolPtr(true)
 
-	ctx := NewTestContext()
+	ctx := NewTestContext(config)
 
 	ctx.RegisterModuleType("test", productVariablesDefaultsTestModuleFactory)
 	ctx.RegisterModuleType("defaults", productVariablesDefaultsTestDefaultsFactory)
@@ -303,7 +303,7 @@
 		ctx.BottomUp("variable", VariableMutator).Parallel()
 	})
 
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	FailIfErrored(t, errs)
diff --git a/android/visibility_test.go b/android/visibility_test.go
index cb5ef35..87a295e 100644
--- a/android/visibility_test.go
+++ b/android/visibility_test.go
@@ -1168,7 +1168,7 @@
 	// Create a new config per test as visibility information is stored in the config.
 	config := TestArchConfig(buildDir, nil, "", fs)
 
-	ctx := NewTestArchContext()
+	ctx := NewTestArchContext(config)
 	ctx.RegisterModuleType("mock_library", newMockLibraryModule)
 	ctx.RegisterModuleType("mock_parent", newMockParentFactory)
 	ctx.RegisterModuleType("mock_defaults", defaultsFactory)
@@ -1180,7 +1180,7 @@
 	ctx.PreArchMutators(RegisterDefaultsPreArchMutators)
 	ctx.PreArchMutators(RegisterVisibilityRuleGatherer)
 	ctx.PostDepsMutators(RegisterVisibilityRuleEnforcer)
-	ctx.Register(config)
+	ctx.Register()
 
 	_, errs := ctx.ParseBlueprintsFiles(".")
 	if len(errs) > 0 {