build: add esbuild target for shadow npm inject script

Creates dist/shadow-npm-inject.js from src/shadow/npm/inject.mts.
This inject script is loaded via --require flag when spawning npm
with shadow arborist.

Author: jdalton

packages/cli/.config/esbuild.inject.config.mjs

@@ -0,0 +1,73 @@
+/**
+ * esbuild configuration for building shadow npm inject script.
+ *
+ * This builds the inject script that is loaded via --require flag
+ * when spawning npm with shadow arborist.
+ */
+
+import { writeFileSync } from 'node:fs'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url'
+
+import { build } from 'esbuild'
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url))
+const rootPath = path.join(__dirname, '..')
+
+const config = {
+  entryPoints: [path.join(rootPath, 'src/shadow/npm/inject.mts')],
+  bundle: true,
+  outfile: path.join(rootPath, 'dist/shadow-npm-inject.js'),
+  // Target Node.js environment (not browser).
+  platform: 'node',
+  // Target Node.js 18+ features.
+  target: 'node18',
+  format: 'cjs',
+
+  // With platform: 'node', esbuild automatically externalizes all Node.js built-ins.
+  external: [
+    'node-gyp', // Required for require.resolve('node-gyp/package.json')
+  ],
+
+  // Suppress warnings for intentional CommonJS compatibility code.
+  logOverride: {
+    'commonjs-variable-in-esm': 'silent',
+    'empty-import-meta': 'silent',
+    'require-resolve-not-external': 'silent',
+  },
+
+  // Source maps off for production.
+  sourcemap: false,
+
+  // Don't minify (keep readable for debugging).
+  minify: false,
+
+  // Keep names for better stack traces.
+  keepNames: true,
+
+  // Write directly to disk.
+  write: true,
+
+  // Define environment variables and import.meta.
+  define: {
+    'process.env.NODE_ENV': '"production"',
+    'import.meta.url': '__importMetaUrl',
+  },
+
+  // Inject import.meta.url polyfill for CJS.
+  inject: [path.join(__dirname, 'esbuild-inject-import-meta.mjs')],
+}
+
+// Run build if invoked directly.
+if (fileURLToPath(import.meta.url) === process.argv[1]) {
+  build(config)
+    .then(() => {
+      console.log('Built shadow-npm-inject.js')
+    })
+    .catch(error => {
+      console.error('Build failed:', error)
+      process.exitCode = 1
+    })
+}
+
+export default config

packages/cli/scripts/build.mjs

@@ -117,6 +117,11 @@ async function main() {
         command: 'node',
         args: ['.config/esbuild.index.config.mjs'],
       },
+      {
+        name: 'Build Shadow NPM Inject',
+        command: 'node',
+        args: ['.config/esbuild.inject.config.mjs'],
+      },
       {
         name: 'Compress CLI',
         command: 'node',