Enable Metro caching

Summary:
Enabling Metro cache for dev mode. For release builds we reset the cache.

Cache is used for faster compilation in dev mode for both main and renderer bundles, as well as for plugins.

Currently we have few side effects based on env vars, so cache is invalidated when they are changed. Also the cache is invalidated when transformations are changed (changed code, bumped dependency etc). Also added a script to reset the cache if something is going wrong.

Reviewed By: mweststrate

Differential Revision: D20691464

fbshipit-source-id: 478947d438bd3090f052dbfa6ad5c649523ecacb

desktop/static/compilePlugins.ts

@@ -33,8 +33,6 @@ export type CompileOptions = {
   recompileOnChanges: boolean;
 };
 
-type DynamicCompileOptions = CompileOptions & {force: boolean};
-
 export type PluginManifest = {
   version: string;
   name: string;
@@ -69,10 +67,7 @@ export default async function (
   const compilations = pMap(
     Object.values(plugins),
     (plugin) => {
-      const dynamicOptions: DynamicCompileOptions = Object.assign(options, {
-        force: false,
-      });
-      return compilePlugin(plugin, pluginCache, dynamicOptions);
+      return compilePlugin(plugin, pluginCache, options);
     },
     {concurrency: 4},
   );
@@ -244,11 +239,12 @@ async function mostRecentlyChanged(dir: string) {
 async function compilePlugin(
   pluginInfo: PluginInfo,
   pluginCache: string,
-  options: DynamicCompileOptions,
+  {force, failSilently}: CompileOptions,
 ): Promise<CompiledPluginInfo | null> {
   const {rootDir, manifest, entry, name} = pluginInfo;
   const bundleMain = manifest.bundleMain ?? path.join('dist', 'index.js');
   const bundlePath = path.join(rootDir, bundleMain);
+  const dev = process.env.NODE_ENV !== 'production';
   if (await fs.pathExists(bundlePath)) {
     // eslint-disable-next-line no-console
     const out = path.join(rootDir, bundleMain);
@@ -262,7 +258,7 @@ async function compilePlugin(
     const result = Object.assign({}, pluginInfo.manifest, {out});
     const rootDirCtime = await mostRecentlyChanged(rootDir);
     if (
-      !options.force &&
+      !force &&
       (await fs.pathExists(out)) &&
       rootDirCtime < (await fs.lstat(out)).ctime
     ) {
@@ -296,13 +292,14 @@ async function compilePlugin(
           {
             entry: entry.replace(rootDir, '.'),
             out,
-            dev: false,
+            dev,
             sourceMap: true,
             minify: false,
+            resetCache: !dev,
           },
         );
       } catch (e) {
-        if (options.failSilently) {
+        if (failSilently) {
           console.error(
             `❌  Plugin ${name} is ignored, because it could not be compiled.`,
           );