From 7ae8483d21f3f5a229e48a9aabb5d1c0402d4045 Mon Sep 17 00:00:00 2001
From: Pooya Parsa <pyapar@gmail.com>
Date: Sat, 28 Nov 2020 22:11:14 +0100
Subject: [PATCH] feat: support typescript via esbuild (closes #42)

---
 packages/nitro/src/module/nuxt2.ts   |   3 +
 packages/nitro/src/rollup/config.ts  |   4 +
 packages/nitro/src/rollup/esbuild.ts | 165 +++++++++++++++++++++++++++
 3 files changed, 172 insertions(+)
 create mode 100644 packages/nitro/src/rollup/esbuild.ts

diff --git a/packages/nitro/src/module/nuxt2.ts b/packages/nitro/src/module/nuxt2.ts
index 9682cdc27a..b80a17088c 100644
--- a/packages/nitro/src/module/nuxt2.ts
+++ b/packages/nitro/src/module/nuxt2.ts
@@ -30,6 +30,9 @@ export default function (nuxt, moduleContainer) {
   // Expose process.env.SIGMA_PRESET
   nuxt.options.env.SIGMA_PRESET = sigmaContext.preset
 
+  // .ts is supported for serverMiddleware
+  nuxt.options.extensions.push('ts')
+
   // Replace nuxt server
   if (nuxt.server) {
     nuxt.server.__closed = true
diff --git a/packages/nitro/src/rollup/config.ts b/packages/nitro/src/rollup/config.ts
index 0a69e70aaf..748693819a 100644
--- a/packages/nitro/src/rollup/config.ts
+++ b/packages/nitro/src/rollup/config.ts
@@ -20,6 +20,7 @@ import { dynamicRequire } from './dynamic-require'
 import { externals } from './externals'
 import { timing } from './timing'
 import { autoMock } from './automock'
+import esbuild from './esbuild'
 
 export type RollupConfig = InputOptions & { output: OutputOptions }
 
@@ -110,6 +111,9 @@ export const getRollupConfig = (sigmaContext: SigmaContext) => {
     }
   }))
 
+  // ESBuild (typescript)
+  rollupConfig.plugins.push(esbuild({}))
+
   // Dynamic Require Support
   rollupConfig.plugins.push(dynamicRequire({
     dir: resolve(sigmaContext._nuxt.buildDir, 'dist/server'),
diff --git a/packages/nitro/src/rollup/esbuild.ts b/packages/nitro/src/rollup/esbuild.ts
new file mode 100644
index 0000000000..163aa27256
--- /dev/null
+++ b/packages/nitro/src/rollup/esbuild.ts
@@ -0,0 +1,165 @@
+// Based on https://github.com/egoist/rollup-plugin-esbuild (MIT)
+
+import { existsSync, statSync } from 'fs'
+import { extname, resolve, dirname, join, relative } from 'path'
+import { Plugin, PluginContext } from 'rollup'
+import { startService, Loader, Service, TransformResult } from 'esbuild'
+import { createFilter, FilterPattern } from '@rollup/pluginutils'
+
+const defaultLoaders: { [ext: string]: Loader } = {
+  '.ts': 'ts'
+}
+
+export type Options = {
+  include?: FilterPattern
+  exclude?: FilterPattern
+  sourceMap?: boolean
+  minify?: boolean
+  target?: string | string[]
+  jsxFactory?: string
+  jsxFragment?: string
+  define?: {
+    [k: string]: string
+  }
+  /**
+   * Use this tsconfig file instead
+   * Disable it by setting to `false`
+   */
+  tsconfig?: string | false
+  /**
+   * Map extension to esbuild loader
+   * Note that each entry (the extension) needs to start with a dot
+   */
+  loaders?: {
+    [ext: string]: Loader | false
+  }
+}
+
+export default (options: Options = {}): Plugin => {
+  let target: string | string[]
+
+  const loaders = {
+    ...defaultLoaders
+  }
+
+  if (options.loaders) {
+    for (const key of Object.keys(options.loaders)) {
+      const value = options.loaders[key]
+      if (typeof value === 'string') {
+        loaders[key] = value
+      } else if (value === false) {
+        delete loaders[key]
+      }
+    }
+  }
+
+  const extensions: string[] = Object.keys(loaders)
+  const INCLUDE_REGEXP = new RegExp(
+    `\\.(${extensions.map(ext => ext.slice(1)).join('|')})$`
+  )
+  const EXCLUDE_REGEXP = /node_modules/
+
+  const filter = createFilter(
+    options.include || INCLUDE_REGEXP,
+    options.exclude || EXCLUDE_REGEXP
+  )
+
+  let service: Service | undefined
+
+  const stopService = () => {
+    if (service) {
+      service.stop()
+      service = undefined
+    }
+  }
+
+  return {
+    name: 'esbuild',
+
+    async buildStart () {
+      if (!service) {
+        service = await startService()
+      }
+    },
+
+    async transform (code, id) {
+      if (!filter(id)) {
+        return null
+      }
+
+      const ext = extname(id)
+      const loader = loaders[ext]
+
+      if (!loader || !service) {
+        return null
+      }
+
+      target = options.target || 'node12'
+
+      const result = await service.transform(code, {
+        loader,
+        target,
+        define: options.define,
+        sourcemap: options.sourceMap !== false,
+        sourcefile: id
+      })
+
+      printWarnings(id, result, this)
+
+      return (
+        result.code && {
+          code: result.code,
+          map: result.map || null
+        }
+      )
+    },
+
+    buildEnd (error) {
+      // Stop the service early if there's error
+      if (error && !this.meta.watchMode) {
+        stopService()
+      }
+    },
+
+    async renderChunk (code) {
+      if (options.minify && service) {
+        const result = await service.transform(code, {
+          loader: 'js',
+          minify: true,
+          target
+        })
+        if (result.code) {
+          return {
+            code: result.code,
+            map: result.map || null
+          }
+        }
+      }
+      return null
+    },
+
+    generateBundle () {
+      if (!this.meta.watchMode) {
+        stopService()
+      }
+    }
+  }
+}
+
+function printWarnings (
+  id: string,
+  result: TransformResult,
+  plugin: PluginContext
+) {
+  if (result.warnings) {
+    for (const warning of result.warnings) {
+      let message = '[esbuild]'
+      if (warning.location) {
+        message += ` (${relative(process.cwd(), id)}:${warning.location.line}:${warning.location.column
+          })`
+      }
+      message += ` ${warning.text}`
+      plugin.warn(message)
+    }
+  }
+}