From 55c26d2790b8502f115180cfe02aba5720c84b7b Mon Sep 17 00:00:00 2001
From: Floriel <Ffloriel@users.noreply.github.com>
Date: Wed, 23 Feb 2022 19:19:54 +0000
Subject: [PATCH] feat(gulp-purgecss): add support for gulp-sourcemaps #257

---
 package-lock.json                       | 32 +++++++++++++++++++++++++
 packages/gulp-purgecss/package.json     |  3 ++-
 packages/gulp-purgecss/src/index.ts     | 18 +++++++++++---
 packages/gulp-purgecss/tsconfig.json    |  5 ++--
 types/vinyl-sourcemaps-apply/index.d.ts |  1 +
 5 files changed, 53 insertions(+), 6 deletions(-)
 create mode 100644 types/vinyl-sourcemaps-apply/index.d.ts

diff --git a/package-lock.json b/package-lock.json
index 77dd0443..c26a45a8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -48,6 +48,7 @@
 				"through2": "^4.0.1",
 				"twing": "^5.1.0",
 				"vinyl": "^2.2.0",
+				"vinyl-sourcemaps-apply": "^0.2.1",
 				"webpack": ">=5.0.0"
 			},
 			"devDependencies": {
@@ -15338,6 +15339,22 @@
 				"node": ">= 0.10"
 			}
 		},
+		"node_modules/vinyl-sourcemaps-apply": {
+			"version": "0.2.1",
+			"resolved": "https://registry.npmjs.org/vinyl-sourcemaps-apply/-/vinyl-sourcemaps-apply-0.2.1.tgz",
+			"integrity": "sha1-q2VJ1h0XLCsbh75cUI0jnI74dwU=",
+			"dependencies": {
+				"source-map": "^0.5.1"
+			}
+		},
+		"node_modules/vinyl-sourcemaps-apply/node_modules/source-map": {
+			"version": "0.5.7",
+			"resolved": "https://registry.npmjs.org/source-map/-/source-map-0.5.7.tgz",
+			"integrity": "sha1-igOdLRAh0i0eoUyA2OpGi6LvP8w=",
+			"engines": {
+				"node": ">=0.10.0"
+			}
+		},
 		"node_modules/vinyl/node_modules/clone": {
 			"version": "2.1.2",
 			"resolved": "https://registry.npmjs.org/clone/-/clone-2.1.2.tgz",
@@ -28111,6 +28128,21 @@
 				}
 			}
 		},
+		"vinyl-sourcemaps-apply": {
+			"version": "0.2.1",
+			"resolved": "https://registry.npmjs.org/vinyl-sourcemaps-apply/-/vinyl-sourcemaps-apply-0.2.1.tgz",
+			"integrity": "sha1-q2VJ1h0XLCsbh75cUI0jnI74dwU=",
+			"requires": {
+				"source-map": "^0.5.1"
+			},
+			"dependencies": {
+				"source-map": {
+					"version": "0.5.7",
+					"resolved": "https://registry.npmjs.org/source-map/-/source-map-0.5.7.tgz",
+					"integrity": "sha1-igOdLRAh0i0eoUyA2OpGi6LvP8w="
+				}
+			}
+		},
 		"vite": {
 			"version": "2.8.4",
 			"resolved": "https://registry.npmjs.org/vite/-/vite-2.8.4.tgz",
diff --git a/packages/gulp-purgecss/package.json b/packages/gulp-purgecss/package.json
index f453c8b3..3db982cc 100644
--- a/packages/gulp-purgecss/package.json
+++ b/packages/gulp-purgecss/package.json
@@ -47,7 +47,8 @@
     "@types/through2": "^2.0.34",
     "@types/vinyl": "^2.0.4",
     "event-stream": "^4.0.1",
-    "vinyl": "^2.2.0"
+    "vinyl": "^2.2.0",
+    "vinyl-sourcemaps-apply": "^0.2.1"
   },
   "bugs": {
     "url": "https://github.com/FullHuman/purgecss/issues"
diff --git a/packages/gulp-purgecss/src/index.ts b/packages/gulp-purgecss/src/index.ts
index 44bddeff..f0ad2c37 100644
--- a/packages/gulp-purgecss/src/index.ts
+++ b/packages/gulp-purgecss/src/index.ts
@@ -4,6 +4,7 @@ import { PurgeCSS } from "purgecss";
 import * as internal from "stream";
 import through from "through2";
 import VinylFile from "vinyl";
+import applySourceMap from "vinyl-sourcemaps-apply";
 import { UserDefinedOptions } from "./types";
 
 export { UserDefinedOptions };
@@ -17,10 +18,10 @@ function getFiles(contentArray: string[]): string[] {
 }
 
 /**
- * 
+ *
  * @param options - options
- * @returns 
- * 
+ * @returns
+ *
  * @public
  */
 function gulpPurgeCSS(options: UserDefinedOptions): internal.Transform {
@@ -39,6 +40,7 @@ function gulpPurgeCSS(options: UserDefinedOptions): internal.Transform {
             },
           ],
           stdin: true,
+          sourceMap: !!file.sourceMap
         };
         const purgedCSSResults = await new PurgeCSS().purge(optionsGulp);
         const purge = purgedCSSResults[0];
@@ -47,6 +49,11 @@ function gulpPurgeCSS(options: UserDefinedOptions): internal.Transform {
             ? purge.rejected.join(" {}\n") + " {}"
             : purge.css;
         file.contents = Buffer.from(result, "utf-8");
+
+        // apply source map to the chain
+        if (file.sourceMap) {
+          applySourceMap(file, purge.sourceMap);
+        }
         callback(null, file);
       } catch (e: unknown) {
         if (e instanceof Error) {
@@ -70,6 +77,7 @@ function gulpPurgeCSS(options: UserDefinedOptions): internal.Transform {
                   raw: css,
                 },
               ],
+              sourceMap: !!file.sourceMap
             };
 
             const purgedCSSResults = await new PurgeCSS().purge(optionsGulp);
@@ -82,6 +90,10 @@ function gulpPurgeCSS(options: UserDefinedOptions): internal.Transform {
             const streamResult = through();
             streamResult.write(Buffer.from(result, "utf-8"));
             file.contents = file.contents.pipe(streamResult);
+            // apply source map to the chain
+            if (file.sourceMap) {
+              applySourceMap(file, purge.sourceMap);
+            }
             callback(null, file);
           } catch (e: unknown) {
             if (e instanceof Error) {
diff --git a/packages/gulp-purgecss/tsconfig.json b/packages/gulp-purgecss/tsconfig.json
index 9b6f4c1c..3e40fbc6 100644
--- a/packages/gulp-purgecss/tsconfig.json
+++ b/packages/gulp-purgecss/tsconfig.json
@@ -7,8 +7,9 @@
       "baseUrl": ".",
       "paths": {
         "purgecss": ["../purgecss/src"],
-      }
+      },
+      "typeRoots": ["./../../types", "./../../node_modules/@types"]
   },
-  "include": ["./src/**/*", "./rollup.config.ts", "./../purgecss/src/*"],
+  "include": ["src", "./../purgecss/src/*", "./../../types/**/*"],
   "exclude": ["./lib"]
 }
\ No newline at end of file
diff --git a/types/vinyl-sourcemaps-apply/index.d.ts b/types/vinyl-sourcemaps-apply/index.d.ts
new file mode 100644
index 00000000..f9846d69
--- /dev/null
+++ b/types/vinyl-sourcemaps-apply/index.d.ts
@@ -0,0 +1 @@
+declare module 'vinyl-sourcemaps-apply';
\ No newline at end of file