Generate Tests

Summary:
To ensure greater type safety, we want to generate some cpp tests for the fromRawValue conversions

This diff adds support to generate Tests.cpp along with the `buck test` targets itegrated into the rn_codegen rule automatically. The tests just `assert(true, true)` as a starting point

Reviewed By: fkgozali

Differential Revision: D14739493

fbshipit-source-id: fc9dea64ea31e6af7d997aebc54cfd459d48bf4f

Author: rickhanlonii

Diff for: packages/react-native-codegen/DEFS.bzl

@@ -1,9 +1,11 @@
+load("@fbsource//tools/build_defs:default_platform_defs.bzl", "IOS", "MACOSX")
 load("@fbsource//tools/build_defs:fb_native_wrapper.bzl", "fb_native")
 load("@fbsource//tools/build_defs/apple:flag_defs.bzl", "get_debug_preprocessor_flags")
 load(
     "//tools/build_defs/oss:rn_defs.bzl",
     "ANDROID",
     "APPLE",
+    "fb_xplat_cxx_test",
     "get_apple_compiler_flags",
     "get_apple_inspector_flags",
     "react_native_xplat_target",
@@ -31,6 +33,7 @@ def rn_codegen(
     generate_event_emitter_cpp_name = "generate_event_emitter_cpp-{}".format(name)
     generate_event_emitter_h_name = "generate_event_emitter_h-{}".format(name)
     generate_props_cpp_name = "generate_props_cpp-{}".format(name)
+    generate_tests_cpp_name = "generate_tests_cpp-{}".format(name)
     generate_props_h_name = "generated_props_h-{}".format(name)
     generate_shadow_node_cpp_name = "generated_shadow_node_cpp-{}".format(name)
     generate_shadow_node_h_name = "generated_shadow_node_h-{}".format(name)
@@ -66,6 +69,12 @@ def rn_codegen(
         out = "Props.cpp",
     )
 
+    fb_native.genrule(
+        name = generate_tests_cpp_name,
+        cmd = "cp $(location :{})/Tests.cpp $OUT".format(generate_fixtures_rule_name),
+        out = "Tests.cpp",
+    )
+
     fb_native.genrule(
         name = generate_props_h_name,
         cmd = "cp $(location :{})/Props.h $OUT".format(generate_fixtures_rule_name),
@@ -87,6 +96,7 @@ def rn_codegen(
     # libs
     rn_xplat_cxx_library(
         name = "generated_components-{}".format(name),
+        tests = [":generated_tests-{}".format(name)],
         srcs = [
             ":{}".format(generate_event_emitter_cpp_name),
             ":{}".format(generate_props_cpp_name),
@@ -134,3 +144,23 @@ def rn_codegen(
             react_native_xplat_target("fabric/components/view:view"),
         ],
     )
+
+    # Tests
+    fb_xplat_cxx_test(
+        name = "generated_tests-{}".format(name),
+        srcs = [
+            ":{}".format(generate_tests_cpp_name),
+        ],
+        compiler_flags = [
+            "-fexceptions",
+            "-frtti",
+            "-std=c++14",
+            "-Wall",
+        ],
+        contacts = ["[email protected]"],
+        apple_sdks = (IOS, MACOSX),
+        platforms = (ANDROID, APPLE),
+        deps = [
+            "fbsource//xplat/third-party/gmock:gtest",
+        ],
+    )

Diff for: packages/react-native-codegen/src/generators/GenerateTests.js

@@ -0,0 +1,43 @@
+/**
+ * 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.
+ *
+ * @flow strict
+ * @format
+ */
+
+'use strict';
+
+import type {SchemaType} from '../CodegenSchema';
+
+// File path -> contents
+type FilesOutput = Map<string, string>;
+
+const template = `
+/**
+ * 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.
+ */
+
+#include <gtest/gtest.h>
+
+TEST(::_COMPONENT_NAME_::, etc) {
+
+  ASSERT_EQ(true, true);
+}
+`;
+
+module.exports = {
+  generate(libraryName: string, schema: SchemaType): FilesOutput {
+    const fileName = 'Tests.cpp';
+
+    const replacedTemplate = template
+      .replace('::_COMPONENT_NAME_::', libraryName)
+      .trim();
+    return new Map([[fileName, replacedTemplate]]);
+  },
+};

Diff for: packages/react-native-codegen/src/generators/RNCodegen.js

@@ -22,6 +22,7 @@ const generateEventEmitterCpp = require('./GenerateEventEmitterCpp.js');
 const generateEventEmitterH = require('./GenerateEventEmitterH.js');
 const generatePropsCpp = require('./GeneratePropsCpp.js');
 const generatePropsH = require('./GeneratePropsH.js');
+const generateTests = require('./GenerateTests.js');
 const generateShadowNodeCpp = require('./GenerateShadowNodeCpp.js');
 const generateShadowNodeH = require('./GenerateShadowNodeH.js');
 const generateViewConfigJs = require('./GenerateViewConfigJs.js');
@@ -53,6 +54,7 @@ module.exports = {
       ...generateEventEmitterH.generate(libraryName, schema),
       ...generatePropsCpp.generate(libraryName, schema),
       ...generatePropsH.generate(libraryName, schema),
+      ...generateTests.generate(libraryName, schema),
       ...generateShadowNodeCpp.generate(libraryName, schema),
       ...generateShadowNodeH.generate(libraryName, schema),
       ...generateViewConfigJs.generate(libraryName, schema),