From 1e7f339f2fef0aa5e1c08bfabab2c1b42684883c Mon Sep 17 00:00:00 2001
From: Lukas Taegert-Atkinson <lukas.taegert-atkinson@tngtech.com>
Date: Thu, 11 Aug 2022 07:34:13 +0200
Subject: [PATCH] Support inline sourcemaps

---
 src/rollup/rollup.ts                          |  1 +
 src/utils/renderChunks.ts                     | 17 +++++++++---
 .../_config.js                                | 26 +++++++++++++++++++
 .../sourcemap-inline-generatebundle/main.js   |  1 +
 4 files changed, 42 insertions(+), 3 deletions(-)
 create mode 100644 test/function/samples/sourcemap-inline-generatebundle/_config.js
 create mode 100644 test/function/samples/sourcemap-inline-generatebundle/main.js

diff --git a/src/rollup/rollup.ts b/src/rollup/rollup.ts
index 6ee5f34d680..ff4e146d02e 100644
--- a/src/rollup/rollup.ts
+++ b/src/rollup/rollup.ts
@@ -281,6 +281,7 @@ async function writeOutputFile(
 	// 'recursive: true' does not throw if the folder structure, or parts of it, already exist
 	await fs.mkdir(dirname(fileName), { recursive: true });
 
+	// TODO Lukas move logic before generateBundle
 	let writeSourceMapPromise: Promise<void> | undefined;
 	let source: string | Uint8Array;
 	if (outputFile.type === 'asset') {
diff --git a/src/utils/renderChunks.ts b/src/utils/renderChunks.ts
index ac9ee1c6d4a..f04cc3235a9 100644
--- a/src/utils/renderChunks.ts
+++ b/src/utils/renderChunks.ts
@@ -20,6 +20,7 @@ import {
 	replaceSinglePlaceholder
 } from './hashPlaceholders';
 import { normalize, resolve } from './path';
+import { SOURCEMAPPING_URL } from './sourceMappingURL';
 import { timeEnd, timeStart } from './timers';
 
 interface HashResult {
@@ -70,7 +71,8 @@ export async function renderChunks(
 		renderedChunksByPlaceholder,
 		hashesByPlaceholder,
 		outputBundle,
-		nonHashedChunksWithPlaceholders
+		nonHashedChunksWithPlaceholders,
+		outputOptions
 	);
 
 	timeEnd('transform chunks', 2);
@@ -286,7 +288,8 @@ function addChunksToBundle(
 	renderedChunksByPlaceholder: Map<string, RenderedChunkWithPlaceholders>,
 	hashesByPlaceholder: Map<string, string>,
 	outputBundle: OutputBundleWithPlaceholders,
-	nonHashedChunksWithPlaceholders: RenderedChunkWithPlaceholders[]
+	nonHashedChunksWithPlaceholders: RenderedChunkWithPlaceholders[],
+	{ sourcemap }: NormalizedOutputOptions
 ) {
 	for (const { chunk, code, fileName, map } of renderedChunksByPlaceholder.values()) {
 		const updatedCode = replacePlaceholders(code, hashesByPlaceholder);
@@ -297,9 +300,17 @@ function addChunksToBundle(
 		outputBundle[finalFileName] = chunk.generateOutputChunk(updatedCode, map, hashesByPlaceholder);
 	}
 	for (const { chunk, code, fileName, map } of nonHashedChunksWithPlaceholders) {
-		const updatedCode = hashesByPlaceholder.size
+		let updatedCode = hashesByPlaceholder.size
 			? replacePlaceholders(code, hashesByPlaceholder)
 			: code;
+		// TODO Lukas use shared code for placeholder files above
+		// TODO Lukas support other sourcemap options
+		if (map) {
+			if (sourcemap === 'inline') {
+				const url = map.toUrl();
+				updatedCode += `//# ${SOURCEMAPPING_URL}=${url}\n`;
+			}
+		}
 		outputBundle[fileName] = chunk.generateOutputChunk(updatedCode, map, hashesByPlaceholder);
 	}
 }
diff --git a/test/function/samples/sourcemap-inline-generatebundle/_config.js b/test/function/samples/sourcemap-inline-generatebundle/_config.js
new file mode 100644
index 00000000000..ba1c28f2eff
--- /dev/null
+++ b/test/function/samples/sourcemap-inline-generatebundle/_config.js
@@ -0,0 +1,26 @@
+const assert = require('assert');
+
+module.exports = {
+	solo: true,
+	description: 'includes inline sourcemap comments in generateBundle hook',
+	options: {
+		plugins: [
+			{
+				name: 'test',
+				generateBundle(options, bundle) {
+					assert.strictEqual(
+						bundle['main.js'].code,
+						`'use strict';
+
+var main = 42;
+
+module.exports = main;
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJmaWxlIjoibWFpbi5qcyIsInNvdXJjZXMiOlsibWFpbi5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyJleHBvcnQgZGVmYXVsdCA0MjtcbiJdLCJuYW1lcyI6W10sIm1hcHBpbmdzIjoiOztBQUFBLFdBQWUsRUFBRTs7OzsifQ==
+`
+					);
+				}
+			}
+		],
+		output: { sourcemap: 'inline' }
+	}
+};
diff --git a/test/function/samples/sourcemap-inline-generatebundle/main.js b/test/function/samples/sourcemap-inline-generatebundle/main.js
new file mode 100644
index 00000000000..7a4e8a723a4
--- /dev/null
+++ b/test/function/samples/sourcemap-inline-generatebundle/main.js
@@ -0,0 +1 @@
+export default 42;