yarn-plugin: remove dependency on chalk

Chalk costs us about 20kb in the bundle size, and
we only use it to format one logged message. To
avoid this dependency, this commit hard-codes the
escape codes for that single message.

Signed-off-by: MT Lewis <mtlewis@users.noreply.github.com>

packages/yarn-plugin/package.json

@@ -34,7 +34,6 @@
     "@backstage/release-manifests": "workspace:^",
     "@yarnpkg/core": "^4.0.3",
     "@yarnpkg/fslib": "^3.0.2",
-    "chalk": "^4.0.0",
     "lodash": "^4.17.21",
     "semver": "^7.6.0"
   },

packages/yarn-plugin/src/index.ts

@@ -22,16 +22,20 @@
  */
 
 import { Plugin, semverUtils, YarnVersion } from '@yarnpkg/core';
-import chalk from 'chalk';
 import { beforeWorkspacePacking } from './handlers/beforeWorkspacePacking';
 import { BackstageResolver } from './resolver/BackstageResolver';
 
+// All dependencies of the yarn plugin are bundled during the build. Chalk
+// triples the size of the plugin bundle when included, so we avoid the
+// dependency by hard-coding the ANSI escape codes for the one bit of formatting
+// we need.
+const RED_BOLD = `\u001B[31;1m`;
+const RESET = '\u001B[0m';
+
 if (!semverUtils.satisfiesWithPrereleases(YarnVersion, '^4.1.1')) {
   console.error();
   console.error(
-    `${chalk.bold.red(
-      'Unsupported yarn version.',
-    )}: The Backstage yarn plugin only works with yarn ^4.1.1. Please upgrade yarn, or remove this plugin with "yarn plugin remove @yarnpkg/plugin-backstage".`,
+    `${RED_BOLD}Unsupported yarn version${RESET}: The Backstage yarn plugin only works with yarn ^4.1.1. Please upgrade yarn, or remove this plugin with "yarn plugin remove @yarnpkg/plugin-backstage".`,
   );
   console.error();
 }

yarn.lock

@@ -45427,7 +45427,6 @@ __metadata:
     "@yarnpkg/builder": ^4.0.0
     "@yarnpkg/core": ^4.0.3
     "@yarnpkg/fslib": ^3.0.2
-    chalk: ^4.0.0
     lodash: ^4.17.21
     nodemon: ^3.0.1
     semver: ^7.6.0