Plugin env

plugins/env.ts

@@ -0,0 +1,31 @@
+import { Plugin } from '../types.ts';
+
+export const defaultMatcher = /{{([^}]*)}}/ig;
+
+type Options = {
+  matcher?: string | RegExp,
+}
+const defaultOptions: Options = {
+  matcher: defaultMatcher,
+}
+const env = (options: Options = defaultOptions): Plugin => ({
+  name: 'env',
+  test: /\.[tj]s[x]?$/,
+  acceptHMR: true,
+  async transform(content: Uint8Array) {
+    const parameters = Deno.env.toObject();
+    const string = (new TextDecoder()).decode(content);
+    const code = string
+      .replaceAll(options.matcher!, (raw, match) => {
+        if (match in parameters) {
+          return String(parameters[match]);
+        }
+        return raw;
+      });
+    return {
+      code,
+    }
+  }
+})
+
+export default env;

plugins/env_test.ts

@@ -0,0 +1,38 @@
+import { assertEquals, assert } from 'https://deno.land/std/testing/asserts.ts';
+import env from './env.ts';
+
+Deno.env.set('TEST_ENV_VAR', '1')
+
+Deno.test('env loader should accept ts files', async () => {
+  const plugin = env();
+  assert(plugin.test.test('mod.ts'));
+})
+
+Deno.test('env loader should accept tsx files', async () => {
+  const plugin = env();
+  assert(plugin.test.test('mod.tsx'));
+})
+
+Deno.test('env loader should accept js files', async () => {
+  const plugin = env();
+  assert(plugin.test.test('mod.js'));
+})
+
+Deno.test('env loader should accept jsx files', async () => {
+  const plugin = env();
+  assert(plugin.test.test('mod.jsx'));
+})
+
+Deno.test('env loader should be accept HMR files', async () => {
+  const plugin = env();
+  assert(plugin.acceptHMR);
+})
+
+Deno.test('env loader should replace env variables', async () => {
+  const plugin = env();
+  const { code, loader } = await plugin.transform?.(
+    (new TextEncoder).encode('const start = {{TEST_ENV_VAR}};'),
+    'mod.ts'
+  )!
+  assertEquals(code, 'const start = 1;')
+})