Add unit tests for RCTComponentViewRegistry

Summary:
Changelog: [internal]

Adds unit tests for `RCTComponentViewRegistry`.

Reviewed By: shergin

Differential Revision: D24391419

fbshipit-source-id: e8adb641361c3e1394f652a1819f196d2402f493

Author: sammy-SC

React/Tests/Mounting/RCTComponentViewRegistryTests.mm

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <React/RCTComponentViewRegistry.h>
+#import <React/RCTViewComponentView.h>
+#import <XCTest/XCTest.h>
+
+@interface RCTComponentViewRegistryTests : XCTestCase
+@end
+
+using namespace facebook::react;
+
+@implementation RCTComponentViewRegistryTests {
+  RCTComponentViewRegistry *_componentViewRegistry;
+}
+
+- (void)setUp
+{
+  [super setUp];
+  _componentViewRegistry = [RCTComponentViewRegistry new];
+}
+
+- (void)testComponentViewDescriptorWithTag
+{
+  XCTAssertThrows(
+      ^{
+        Tag nonExistingTag = 12;
+        [self->_componentViewRegistry componentViewDescriptorWithTag:nonExistingTag];
+      }(),
+      @"Should throw: `Attempt to query unregistered component`");
+
+  Tag existingTag = 2;
+  auto newViewDescriptor = [_componentViewRegistry
+      dequeueComponentViewWithComponentHandle:[RCTViewComponentView componentDescriptorProvider].handle
+                                          tag:existingTag];
+
+  XCTAssertNoThrow(^{
+    auto componentDescriptor = [self->_componentViewRegistry componentViewDescriptorWithTag:existingTag];
+    XCTAssertEqual(newViewDescriptor, componentDescriptor);
+  }());
+}
+
+- (void)testFindComponentViewWithTag
+{
+  Tag nonExistingTag = 12;
+  XCTAssertNil([_componentViewRegistry findComponentViewWithTag:nonExistingTag]);
+
+  Tag existingTag = 2;
+  auto newViewDescriptor = [_componentViewRegistry
+      dequeueComponentViewWithComponentHandle:[RCTViewComponentView componentDescriptorProvider].handle
+                                          tag:existingTag];
+
+  XCTAssertEqual(newViewDescriptor.view, [_componentViewRegistry findComponentViewWithTag:existingTag]);
+}
+
+- (void)testDequeueAndEnqueue
+{
+  Tag existingTag = 2;
+  auto newViewDescriptor = [_componentViewRegistry
+      dequeueComponentViewWithComponentHandle:[RCTViewComponentView componentDescriptorProvider].handle
+                                          tag:existingTag];
+
+  XCTAssertThrows(
+      ^{
+        [self->_componentViewRegistry
+            dequeueComponentViewWithComponentHandle:[RCTViewComponentView componentDescriptorProvider].handle
+                                                tag:existingTag];
+      }(),
+      @"Should throw: `Attempt to dequeue already registered component`");
+
+  XCTAssertThrows(
+      ^{
+        Tag nonExistingTag = 12;
+        [self->_componentViewRegistry
+            enqueueComponentViewWithComponentHandle:[RCTViewComponentView componentDescriptorProvider].handle
+                                                tag:nonExistingTag
+                            componentViewDescriptor:newViewDescriptor];
+      }(),
+      @"Should throw: `Attempt to enqueue unregistered component`");
+}
+
+@end

React/Tests/Text/RCTParagraphComponentViewTests.mm

@@ -9,24 +9,24 @@
 #import <React/RCTParagraphComponentView.h>
 
 #import <XCTest/XCTest.h>
-#import <react/attributedstring/AttributedString.h>
-#import <react/attributedstring/ParagraphAttributes.h>
-#import <react/attributedstring/TextAttributes.h>
-#import <react/componentregistry/ComponentDescriptorProviderRegistry.h>
-#import <react/components/root/RootComponentDescriptor.h>
-#import <react/components/text/ParagraphComponentDescriptor.h>
-#import <react/components/text/ParagraphShadowNode.h>
-#import <react/components/text/ParagraphState.h>
-#import <react/components/text/RawTextComponentDescriptor.h>
-#import <react/components/text/RawTextShadowNode.h>
-#import <react/components/text/TextComponentDescriptor.h>
-#import <react/components/text/TextShadowNode.h>
-#import <react/components/view/ViewComponentDescriptor.h>
-#import <react/element/ComponentBuilder.h>
-#import <react/element/Element.h>
-#import <react/element/testUtils.h>
-#import <react/textlayoutmanager/RCTTextLayoutManager.h>
-#import <react/textlayoutmanager/TextLayoutManager.h>
+#import <react/renderer/attributedstring/AttributedString.h>
+#import <react/renderer/attributedstring/ParagraphAttributes.h>
+#import <react/renderer/attributedstring/TextAttributes.h>
+#import <react/renderer/componentregistry/ComponentDescriptorProviderRegistry.h>
+#import <react/renderer/components/root/RootComponentDescriptor.h>
+#import <react/renderer/components/text/ParagraphComponentDescriptor.h>
+#import <react/renderer/components/text/ParagraphShadowNode.h>
+#import <react/renderer/components/text/ParagraphState.h>
+#import <react/renderer/components/text/RawTextComponentDescriptor.h>
+#import <react/renderer/components/text/RawTextShadowNode.h>
+#import <react/renderer/components/text/TextComponentDescriptor.h>
+#import <react/renderer/components/text/TextShadowNode.h>
+#import <react/renderer/components/view/ViewComponentDescriptor.h>
+#import <react/renderer/element/ComponentBuilder.h>
+#import <react/renderer/element/Element.h>
+#import <react/renderer/element/testUtils.h>
+#import <react/renderer/textlayoutmanager/RCTTextLayoutManager.h>
+#import <react/renderer/textlayoutmanager/TextLayoutManager.h>
 
 @interface RCTParagraphComponentAccessibilityProviderTests : XCTestCase