Add test for js1 build viewconfigs

Summary:
This diff adds a new `--test` option to `js1 build viewconfigs` which will only check that the configs have not changed instead of writing the new/updated files. This will allow us to run sandcastle checks on the view configs

I also improved the output of the script to give better feedback during normal runs including an additional message and a summary of generated files

Reviewed By: TheSavior

Differential Revision: D15372843

fbshipit-source-id: 4988fc2405cc03137b540817e08d4365cb31fc34

packages/react-native-codegen/buck_tests/generate-view-configs-cli.js

@@ -4,7 +4,6 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @emails oncall+react_native
  * @flow
  * @format
  */
@@ -12,17 +11,26 @@
 'use strict';
 
 const generate = require('./generate-view-configs');
+const yargs = require('yargs');
 
-const [fileList] = process.argv.slice(2);
+const yargv = yargs.strict().option('t', {
+  alias: 'test',
+  describe: 'Test the changes and do not write files',
+  requiresArg: false,
+  type: 'boolean',
+});
 
-const CURRENT_VIEW_CONFIG_SCHEMAS = ['SliderSchema.js'];
+const argv = yargv.argv;
+const fileList = argv._[0].split('\n');
+
+const CURRENT_VIEW_CONFIG_SCHEMAS = [''];
 
 generate(
-  fileList
-    .split('\n')
-    .filter(fileName =>
-      CURRENT_VIEW_CONFIG_SCHEMAS.find(supportedFileName =>
-        fileName.endsWith(supportedFileName),
-      ),
+  fileList.filter(fileName =>
+    CURRENT_VIEW_CONFIG_SCHEMAS.find(supportedFileName =>
+      fileName.endsWith(supportedFileName),
     ),
+  ),
+  // $FlowFixMe Type argv
+  argv.test,
 );

packages/react-native-codegen/buck_tests/generate-view-configs.js

@@ -15,20 +15,54 @@ const RNParser = require('../src/generators/RNParser.js');
 
 const path = require('path');
 
-function generate(files: Array<string>): void {
-  files.forEach(filename => {
+type Result = $ReadOnly<{|
+  libraryName: string,
+  success: boolean,
+|}>;
+
+function generateFilesWithResults(
+  files: Array<string>,
+  test: boolean,
+): Array<Result> {
+  return files.reduce((aggregated, filename) => {
     const schema = RNParser.parse(filename);
     if (schema && schema.modules) {
-      RNCodegen.generate(
+      const libraryName = path.basename(filename).replace('Schema.js', '');
+      const success = RNCodegen.generate(
         {
           schema,
+          libraryName,
           outputDirectory: path.dirname(filename),
-          libraryName: path.basename(filename).replace('Schema.js', ''),
         },
-        {generators: ['view-configs']},
+        {generators: ['view-configs'], test},
       );
+
+      aggregated.push({
+        libraryName,
+        success,
+      });
     }
-  });
+    return aggregated;
+  }, []);
+}
+
+function generate(files: Array<string>, test: boolean): void {
+  console.log(`${test ? 'Testing' : 'Generating'} view configs`);
+
+  const results = generateFilesWithResults(files, test);
+
+  const failed = results.filter(result => !result.success);
+  const totalCount = results.length;
+
+  console.log(`\n${test ? 'Tested' : 'Generated'} ${totalCount} view configs`);
+
+  if (failed.length) {
+    if (test === true) {
+      console.error(`${failed.length} configs changed`);
+      console.error("Please re-run 'js1 build viewconfigs'");
+    }
+    process.exit(1);
+  }
 }
 
 module.exports = generate;

packages/react-native-codegen/src/generators/RNCodegen.js

@@ -47,6 +47,7 @@ type Generators =
 
 type Config = $ReadOnly<{|
   generators: Array<Generators>,
+  test?: boolean,
 |}>;
 
 const GENERATORS = {
@@ -61,18 +62,45 @@ const GENERATORS = {
   'view-configs': [generateViewConfigJs.generate],
 };
 
-function writeMapToFiles(map: Map<string, string>, outputDirectory: string) {
+function writeMapToFiles(map: Map<string, string>, outputDir: string) {
+  let success = true;
   map.forEach((contents: string, fileName: string) => {
-    const location = path.join(outputDirectory, fileName);
-    fs.writeFileSync(location, contents);
+    try {
+      const location = path.join(outputDir, fileName);
+      fs.writeFileSync(location, contents);
+    } catch (error) {
+      success = false;
+      console.error(`Failed to write ${fileName} to ${outputDir}`, error);
+    }
   });
+
+  return success;
+}
+
+function checkFilesForChanges(
+  map: Map<string, string>,
+  outputDir: string,
+): boolean {
+  let hasChanged = false;
+
+  map.forEach((contents: string, fileName: string) => {
+    const location = path.join(outputDir, fileName);
+    const currentContents = fs.readFileSync(location, 'utf8');
+    if (currentContents !== contents) {
+      console.error(`- ${fileName} has changed`);
+
+      hasChanged = true;
+    }
+  });
+
+  return !hasChanged;
 }
 
 module.exports = {
   generate(
     {libraryName, schema, outputDirectory}: Options,
-    {generators}: Config,
-  ) {
+    {generators, test}: Config,
+  ): boolean {
     schemaValidator.validate(schema);
 
     const generatedFiles = [];
@@ -82,6 +110,12 @@ module.exports = {
       }
     }
 
-    writeMapToFiles(new Map([...generatedFiles]), outputDirectory);
+    const filesToUpdate = new Map([...generatedFiles]);
+
+    if (test === true) {
+      return checkFilesForChanges(filesToUpdate, outputDirectory);
+    }
+
+    return writeMapToFiles(filesToUpdate, outputDirectory);
   },
 };