Remove varargs from Fixture(t *testing.T)

Bug: 182885307
Test: m nothing
Change-Id: I71c3cf47ba1dc8d29d1533789c4c991cb825bd88
diff --git a/android/fixture.go b/android/fixture.go
index 1eb53a2..303c95c 100644
--- a/android/fixture.go
+++ b/android/fixture.go
@@ -455,7 +455,7 @@
 	Extend(preparers ...FixturePreparer) FixturePreparer
 
 	// Create a Fixture.
-	Fixture(t *testing.T, preparers ...FixturePreparer) Fixture
+	Fixture(t *testing.T) Fixture
 
 	// ExtendWithErrorHandler creates a new FixturePreparer that will use the supplied error handler
 	// to check the errors (may be 0) reported by the test.
@@ -706,13 +706,11 @@
 	NinjaDeps []string
 }
 
-func createFixture(t *testing.T, buildDir string, base []*simpleFixturePreparer, extra []FixturePreparer) Fixture {
-	all := dedupAndFlattenPreparers(base, extra)
-
+func createFixture(t *testing.T, buildDir string, preparers []*simpleFixturePreparer) Fixture {
 	config := TestConfig(buildDir, nil, "", nil)
 	ctx := NewTestContext(config)
 	fixture := &fixture{
-		preparers: all,
+		preparers: preparers,
 		t:         t,
 		config:    config,
 		ctx:       ctx,
@@ -721,7 +719,7 @@
 		errorHandler: FixtureExpectsNoErrors,
 	}
 
-	for _, preparer := range all {
+	for _, preparer := range preparers {
 		preparer.function(fixture)
 	}
 
@@ -741,8 +739,8 @@
 	return newFixturePreparer(all)
 }
 
-func (b *baseFixturePreparer) Fixture(t *testing.T, preparers ...FixturePreparer) Fixture {
-	return createFixture(t, t.TempDir(), b.self.list(), preparers)
+func (b *baseFixturePreparer) Fixture(t *testing.T) Fixture {
+	return createFixture(t, t.TempDir(), b.self.list())
 }
 
 func (b *baseFixturePreparer) ExtendWithErrorHandler(errorHandler FixtureErrorHandler) FixturePreparer {
@@ -812,16 +810,16 @@
 	return extendedFactory
 }
 
-func (f *fixtureFactory) Fixture(t *testing.T, preparers ...FixturePreparer) Fixture {
+func (f *fixtureFactory) Fixture(t *testing.T) Fixture {
 	// If there is no buildDirSupplier then just use the default implementation.
 	if f.buildDirSupplier == nil {
-		return f.baseFixturePreparer.Fixture(t, preparers...)
+		return f.baseFixturePreparer.Fixture(t)
 	}
 
 	// Retrieve the buildDir from the supplier.
 	buildDir := *f.buildDirSupplier
 
-	return createFixture(t, buildDir, f.preparers, preparers)
+	return createFixture(t, buildDir, f.preparers)
 }
 
 type fixture struct {
diff --git a/android/fixture_test.go b/android/fixture_test.go
index 681a034..8f04715 100644
--- a/android/fixture_test.go
+++ b/android/fixture_test.go
@@ -43,43 +43,40 @@
 
 	extension := group.Extend(preparer4, preparer2)
 
-	extension.Fixture(t, preparer1, preparer2, preparer2Then1, preparer3)
+	GroupFixturePreparers(extension, preparer1, preparer2, preparer2Then1, preparer3).Fixture(t)
 
 	AssertDeepEquals(t, "preparers called in wrong order",
 		[]string{"preparer1", "preparer2", "preparer4", "preparer3"}, list)
 }
 
 func TestFixtureValidateMockFS(t *testing.T) {
-	buildDir := "<unused>"
-	factory := NewFixtureFactory(&buildDir)
-
 	t.Run("absolute path", func(t *testing.T) {
 		AssertPanicMessageContains(t, "source path validation failed", "Path is outside directory: /abs/path/Android.bp", func() {
-			factory.Fixture(t, FixtureAddFile("/abs/path/Android.bp", nil))
+			FixtureAddFile("/abs/path/Android.bp", nil).Fixture(t)
 		})
 	})
 	t.Run("not canonical", func(t *testing.T) {
 		AssertPanicMessageContains(t, "source path validation failed", `path "path/with/../in/it/Android.bp" is not a canonical path, use "path/in/it/Android.bp" instead`, func() {
-			factory.Fixture(t, FixtureAddFile("path/with/../in/it/Android.bp", nil))
+			FixtureAddFile("path/with/../in/it/Android.bp", nil).Fixture(t)
 		})
 	})
 	t.Run("FixtureAddFile", func(t *testing.T) {
 		AssertPanicMessageContains(t, "source path validation failed", `cannot add output path "out/Android.bp" to the mock file system`, func() {
-			factory.Fixture(t, FixtureAddFile("out/Android.bp", nil))
+			FixtureAddFile("out/Android.bp", nil).Fixture(t)
 		})
 	})
 	t.Run("FixtureMergeMockFs", func(t *testing.T) {
 		AssertPanicMessageContains(t, "source path validation failed", `cannot add output path "out/Android.bp" to the mock file system`, func() {
-			factory.Fixture(t, FixtureMergeMockFs(MockFS{
+			FixtureMergeMockFs(MockFS{
 				"out/Android.bp": nil,
-			}))
+			}).Fixture(t)
 		})
 	})
 	t.Run("FixtureModifyMockFS", func(t *testing.T) {
 		AssertPanicMessageContains(t, "source path validation failed", `cannot add output path "out/Android.bp" to the mock file system`, func() {
-			factory.Fixture(t, FixtureModifyMockFS(func(fs MockFS) {
+			FixtureModifyMockFS(func(fs MockFS) {
 				fs["out/Android.bp"] = nil
-			}))
+			}).Fixture(t)
 		})
 	})
 }