From 9c18a98f89d7dc98f5fb3b75f74042729f370bf4 Mon Sep 17 00:00:00 2001
From: Pascal Hartig <realpassy@fb.com>
Date: Tue, 21 Apr 2020 02:08:55 -0700
Subject: [PATCH] Enable build minification

Summary: This shaves another ~6MB of the zipped build. Less than I would have thought, but I haven't looked at the alternative options so far at all.

Reviewed By: nikoant

Differential Revision: D21131772

fbshipit-source-id: 641515d6f36fdeeffa5be81d64c2c1043a9e4e34
---
 desktop/package.json            |  1 +
 desktop/pkg-lib/src/runBuild.ts |  9 ++++++++-
 desktop/scripts/build-utils.ts  | 16 ++++++++++++++--
 desktop/yarn.lock               | 26 +++++++++++++++++++++++++-
 4 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/desktop/package.json b/desktop/package.json
index d3585941f..4e19ebaac 100644
--- a/desktop/package.json
+++ b/desktop/package.json
@@ -180,6 +180,7 @@
     "jest-environment-jsdom-sixteen": "^1.0.3",
     "jest-fetch-mock": "^3.0.0",
     "metro": "^0.59.0",
+    "metro-minify-terser": "^0.59.0",
     "metro-resolver": "^0.59.0",
     "p-filter": "^2.1.0",
     "p-map": "^4.0.0",
diff --git a/desktop/pkg-lib/src/runBuild.ts b/desktop/pkg-lib/src/runBuild.ts
index be987025d..38872150b 100644
--- a/desktop/pkg-lib/src/runBuild.ts
+++ b/desktop/pkg-lib/src/runBuild.ts
@@ -77,6 +77,13 @@ export default async function runBuild(
     transformer: {
       ...baseConfig.transformer,
       babelTransformerPath: require.resolve('flipper-babel-transformer'),
+      minifierPath: 'metro-minify-terser',
+      minifierConfig: {
+        // see: https://www.npmjs.com/package/terser
+        keep_fnames: true,
+        module: true,
+        warnings: true,
+      },
     },
     resolver: {
       ...baseConfig.resolver,
@@ -87,7 +94,7 @@ export default async function runBuild(
   });
   await Metro.runBuild(config, {
     dev,
-    minify: false,
+    minify: !dev,
     resetCache: !dev,
     sourceMap: true,
     entry,
diff --git a/desktop/scripts/build-utils.ts b/desktop/scripts/build-utils.ts
index 34d1edd9e..d31df776c 100644
--- a/desktop/scripts/build-utils.ts
+++ b/desktop/scripts/build-utils.ts
@@ -54,6 +54,16 @@ export async function generatePluginEntryPoints() {
   console.log('✅  Generated plugin entry points.');
 }
 
+const minifierConfig = {
+  minifierPath: 'metro-minify-terser',
+  minifierConfig: {
+    // see: https://www.npmjs.com/package/terser
+    keep_fnames: true,
+    module: true,
+    warnings: true,
+  },
+};
+
 async function compile(
   buildFolder: string,
   projectRoot: string,
@@ -71,6 +81,7 @@ async function compile(
           babelTransformationsDir,
           'transform-app',
         ),
+        ...minifierConfig,
       },
       resolver: {
         resolverMainFields: ['flipperBundlerEntry', 'module', 'main'],
@@ -80,7 +91,7 @@ async function compile(
     },
     {
       dev,
-      minify: false,
+      minify: !dev,
       resetCache: !dev,
       sourceMap: true,
       entry,
@@ -145,6 +156,7 @@ export async function compileMain() {
           babelTransformationsDir,
           'transform-main',
         ),
+        ...minifierConfig,
       },
       resolver: {
         sourceExts: ['tsx', 'ts', 'js'],
@@ -157,7 +169,7 @@ export async function compileMain() {
       entry: path.join(staticDir, 'main.ts'),
       out,
       dev,
-      minify: false,
+      minify: !dev,
       sourceMap: true,
       resetCache: !dev,
     });
diff --git a/desktop/yarn.lock b/desktop/yarn.lock
index 42e59ddc0..c7f693845 100644
--- a/desktop/yarn.lock
+++ b/desktop/yarn.lock
@@ -3765,7 +3765,7 @@ combined-stream@^1.0.6, combined-stream@^1.0.8, combined-stream@~1.0.6:
   dependencies:
     delayed-stream "~1.0.0"
 
-commander@^2.11.0, commander@^2.3.0:
+commander@^2.11.0, commander@^2.20.0, commander@^2.3.0:
   version "2.20.3"
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
   integrity sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==
@@ -8331,6 +8331,13 @@ metro-inspector-proxy@0.59.0:
     ws "^1.1.5"
     yargs "^14.2.0"
 
+metro-minify-terser@^0.59.0:
+  version "0.59.0"
+  resolved "https://registry.yarnpkg.com/metro-minify-terser/-/metro-minify-terser-0.59.0.tgz#57dfd539e3de03b59643f05a63af336deade127c"
+  integrity sha512-FSIPTL6+0S1Zyqs/wvypyfM6zxkKTXUHBqodoZMICwKnK0Q+/HeaXOagwY9AXf8LP3NvgGIaM3/qCGIVJnnYkQ==
+  dependencies:
+    terser "^4.6.3"
+
 metro-minify-uglify@0.59.0:
   version "0.59.0"
   resolved "https://registry.yarnpkg.com/metro-minify-uglify/-/metro-minify-uglify-0.59.0.tgz#6491876308d878742f7b894d7fca4af356886dd5"
@@ -10964,6 +10971,14 @@ source-map-support@^0.5.16, source-map-support@^0.5.6, source-map-support@^0.5.9
     buffer-from "^1.0.0"
     source-map "^0.6.0"
 
+source-map-support@~0.5.12:
+  version "0.5.17"
+  resolved "https://registry.yarnpkg.com/source-map-support/-/source-map-support-0.5.17.tgz#29fe1b3c98b9dbd5064ada89052ee8ff070cb46c"
+  integrity sha512-bwdKOBZ5L0gFRh4KOxNap/J/MpvX9Yxsq9lFDx65s3o7F/NiHy7JRaGIS8MwW6tZPAq9UXE207Il0cfcb5yu/Q==
+  dependencies:
+    buffer-from "^1.0.0"
+    source-map "^0.6.0"
+
 source-map-url@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/source-map-url/-/source-map-url-0.4.0.tgz#3e935d7ddd73631b97659956d55128e87b5084a3"
@@ -11420,6 +11435,15 @@ terminal-link@^2.0.0:
     ansi-escapes "^4.2.1"
     supports-hyperlinks "^2.0.0"
 
+terser@^4.6.3:
+  version "4.6.11"
+  resolved "https://registry.yarnpkg.com/terser/-/terser-4.6.11.tgz#12ff99fdd62a26de2a82f508515407eb6ccd8a9f"
+  integrity sha512-76Ynm7OXUG5xhOpblhytE7X58oeNSmC8xnNhjWVo8CksHit0U0kO4hfNbPrrYwowLWFgM2n9L176VNx2QaHmtA==
+  dependencies:
+    commander "^2.20.0"
+    source-map "~0.6.1"
+    source-map-support "~0.5.12"
+
 test-exclude@^5.2.3:
   version "5.2.3"
   resolved "https://registry.yarnpkg.com/test-exclude/-/test-exclude-5.2.3.tgz#c3d3e1e311eb7ee405e092dac10aefd09091eac0"