From a652e98514b0204222b6300e8c1c3f3952a830b3 Mon Sep 17 00:00:00 2001
From: Lexus Drumgold <unicornware@flexdevelopment.llc>
Date: Mon, 7 Aug 2023 20:15:51 -0400
Subject: [PATCH] build: distribute source maps for `utils` only

Signed-off-by: Lexus Drumgold <unicornware@flexdevelopment.llc>
---
 build.config.ts | 75 +++++++++++++++++++++++++++++++++++++++++++++++--
 package.json    |  3 +-
 2 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/build.config.ts b/build.config.ts
index 75840313..139167df 100644
--- a/build.config.ts
+++ b/build.config.ts
@@ -5,6 +5,8 @@
  */
 
 import { defineBuildConfig, type Config } from '@flex-development/mkbuild'
+import pathe from '@flex-development/pathe'
+import type { BuildResult, PluginBuild } from 'esbuild'
 import pkg from './package.json' assert { type: 'json' }
 import tsconfig from './tsconfig.build.json' assert { type: 'json' }
 
@@ -15,8 +17,77 @@ import tsconfig from './tsconfig.build.json' assert { type: 'json' }
  */
 const config: Config = defineBuildConfig({
   charset: 'utf8',
-  sourcemap: true,
-  sourcesContent: false,
+  entries: [
+    { dts: 'only' },
+    { dts: false, pattern: ['internal/*'] },
+    {
+      dts: false,
+      pattern: ['index.ts', 'utils/*'],
+      sourceRoot: pathe.join(
+        pkg.repository.replace(/\.git$/, pathe.sep + 'blob'),
+        pkg.tagPrefix + pkg.version
+      ),
+      sourcemap: true,
+      sourcesContent: false
+    }
+  ],
+  minifySyntax: true,
+  plugins: [
+    {
+      name: 'fix-sourcemaps',
+
+      /**
+       * Makes sourcemap files relative to [`sourceRoot`][1].
+       *
+       * [1]: https://esbuild.github.io/api/#source-root
+       * [2]: https://esbuild.github.io/plugins
+       *
+       * @see https://github.com/evanw/esbuild/issues/2218
+       *
+       * @param {PluginBuild} build - [esbuild plugin api][2]
+       * @param {PluginBuild['onEnd']} build.onEnd - Build end callback
+       * @return {void} Nothing when complete
+       */
+      setup({ initialOptions, onEnd }: PluginBuild): void {
+        return void onEnd((result: BuildResult<{ write: false }>): void => {
+          const { absWorkingDir = process.cwd() } = initialOptions
+
+          return void (result.outputFiles = result.outputFiles.map(output => {
+            if (output.path.endsWith('.map')) {
+              /**
+               * Relative path to output file sourcemap is for.
+               *
+               * **Note**: Relative to {@linkcode absWorkingDir}.
+               *
+               * @const {string} outfile
+               */
+              const outfile: string = output.path
+                .replace(absWorkingDir, '')
+                .replace(/^\//, '')
+                .replace(/\.map$/, '')
+
+              /**
+               * Parsed sourcemap object.
+               *
+               * @const {{ sources: string[] }}
+               */
+              const map: { sources: string[] } = JSON.parse(output.text)
+
+              // reset sources to outfile entry point
+              map.sources = [result.metafile!.outputs[outfile]!.entryPoint!]
+
+              // redefine outfile text
+              Object.defineProperty(output, 'text', {
+                get: (): string => JSON.stringify(map, null, 2)
+              })
+            }
+
+            return output
+          }))
+        })
+      }
+    }
+  ],
   target: [
     pkg.engines.node.replace(/^\D+/, 'node'),
     tsconfig.compilerOptions.target
diff --git a/package.json b/package.json
index 032fe928..0476d3d1 100644
--- a/package.json
+++ b/package.json
@@ -27,8 +27,7 @@
   "type": "module",
   "files": [
     "CHANGELOG.md",
-    "dist",
-    "src"
+    "dist"
   ],
   "exports": {
     ".": "./dist/index.mjs",