[Tabs] Move "Tabs2" into an extension. (#7663)

Rather than having an independent "component" for the new view, it can be
homed as an extension of the existing component. Later migration should be as
simple as updating the umbrella import.

Closes #7655

MaterialComponentsBeta.podspec

@@ -104,17 +104,18 @@ Pod::Spec.new do |mdc|
     end
   end
 
-  mdc.subspec "Tabs2" do |component|
-    component.ios.deployment_target = '9.0'
-    component.public_header_files = "components/#{component.base_name}/src/*.h"
-    component.source_files = [
-      "components/#{component.base_name}/src/*.{h,m}",
-      "components/#{component.base_name}/src/private/*.{h,m}",
+  mdc.subspec "Tabs+TabBarView" do |extension|
+    extension.ios.deployment_target = '9.0'
+    extension.public_header_files = "components/#{extension.base_name.split('+')[0]}/src/#{extension.base_name.split('+')[1]}/*.h"
+    extension.source_files = [
+      "components/#{extension.base_name.split('+')[0]}/src/#{extension.base_name.split('+')[1]}/*.{h,m}",
+      "components/#{extension.base_name.split('+')[0]}/src/#{extension.base_name.split('+')[1]}/private/*.{h,m}"
     ]
+    extension.dependency "MaterialComponents/#{extension.base_name.split('+')[0]}"
 
-    component.test_spec 'UnitTests' do |unit_tests|
+    extension.test_spec 'UnitTests' do |unit_tests|
       unit_tests.source_files = [
-        "components/#{component.base_name}/tests/unit/*.m"
+        "components/#{extension.base_name.split('+')[0]}/tests/unit/#{extension.base_name.split('+')[1]}/*.{h,m,swift}",
       ]
     end
   end

MaterialComponentsSnapshotTests.podspec

@@ -15,8 +15,8 @@ module SnapshotPodspecHelper
         source_files = Dir["components/#{@name}/tests/snapshot/*.{h,m,swift}"]
         supplemental_files = Dir["components/#{@name}/tests/snapshot/supplemental/*.{h,m,swift}"]
         example_files = Dir["components/#{@name}/examples/tests/snapshot/*.{h,m,swift}"]
-        theming_files = Dir["components/#{@name}/tests/snapshot/Theming/*.{h,m,swift}"]
-        return source_files + supplemental_files + example_files + theming_files
+        extension_files = Dir["components/#{@name}/tests/snapshot/*/*.{h,m,swift}"]
+        return source_files + supplemental_files + example_files + extension_files
       end
       return []
     end

catalog/Podfile

@@ -73,7 +73,7 @@ target "MDCCatalog" do
     'ActionSheet+ColorThemer/UnitTests',
     'BottomNavigation/UnitTests',
     'ButtonBar+Theming/UnitTests',
-    'Tabs2/UnitTests',
+    'Tabs+TabBarView/UnitTests',
   ]
   pod 'MaterialComponentsSnapshotTests', :path => '../', :testspecs => [
     'SnapshotTests'

components/Tabs/BUILD

@@ -91,10 +91,15 @@ mdc_extension_objc_library(
     ],
 )
 
+mdc_extension_objc_library(
+    name = "TabBarView",
+)
+
 mdc_examples_objc_library(
     name = "ObjcExamples",
     deps = [
         ":ColorThemer",
+        ":TabBarView",
         ":Tabs",
         ":TypographyThemer",
         "//components/AppBar",
@@ -133,6 +138,13 @@ mdc_objc_library(
     visibility = ["//visibility:private"],
 )
 
+mdc_objc_library(
+    name = "privateTabBarView",
+    hdrs = native.glob(["src/TabBarView/private/*.h"]),
+    includes = ["src/TabBarView/private"],
+    visibility = ["//visibility:private"],
+)
+
 mdc_objc_library(
     name = "unit_test_sources",
     testonly = 1,
@@ -173,20 +185,38 @@ mdc_objc_library(
     ],
 )
 
+mdc_objc_library(
+    name = "unit_test_tabbarview_sources",
+    srcs = native.glob([
+        "tests/unit/TabBarView/*.m",
+    ]),
+    sdk_frameworks = [
+        "CoreGraphics",
+        "XCTest",
+    ],
+    deps = [
+        ":TabBarView",
+        ":privateTabBarView",
+    ],
+)
+
 mdc_unit_test_suite(
     name = "unit_tests",
     deps = [
         ":unit_test_sources",
+        ":unit_test_tabbarview_sources",
         ":unit_test_theming_sources",
     ],
 )
 
 mdc_snapshot_objc_library(
     name = "snapshot_test_lib",
-    extra_srcs = native.glob(["tests/snapshot/Theming/*.m"]),
+    extra_srcs = native.glob(["tests/snapshot/*/*.m"]),
     deps = [
+        ":TabBarView",
         ":Tabs",
         ":Theming",
+        ":privateTabBarView",
     ],
 )
 

components/Tabs2/tests/snapshot/MDCTabBarViewItemViewSnapshotTests.m → components/Tabs/tests/snapshot/TabBarView/MDCTabBarViewItemViewSnapshotTests.m

@@ -15,7 +15,7 @@
 #import <XCTest/XCTest.h>
 
 #import <CoreGraphics/CoreGraphics.h>
-#import "../../src/private/MDCTabBarViewItemView.h"
+#import "../../../src/TabBarView/private/MDCTabBarViewItemView.h"
 #import "MaterialSnapshot.h"
 
 @interface MDCTabBarViewItemViewSnapshotTests : MDCSnapshotTestCase

components/Tabs2/tests/unit/MDCTabBarViewItemViewTests.m → components/Tabs/tests/unit/TabBarView/MDCTabBarViewItemViewTests.m

@@ -15,7 +15,7 @@
 #import <XCTest/XCTest.h>
 
 #import <CoreGraphics/CoreGraphics.h>
-#import "../../src/private/MDCTabBarViewItemView.h"
+#import "../../../src/TabBarView/private/MDCTabBarViewItemView.h"
 
 // Minimum width of an item view.
 static const CGFloat kMinWidth = 90;