Add inputSourceMap option to Node binding

Author: devongovett

node/index.d.ts

@@ -9,6 +9,8 @@ export interface TransformOptions {
   minify?: boolean,
   /** Whether to output a source map. */
   sourceMap?: boolean,
+  /** An input source map to extend. */
+  inputSourceMap?: string,
   /** The browser targets for the generated code. */
   targets?: Targets,
   /** Whether to enable various draft syntax. */

node/src/lib.rs

@@ -169,6 +169,7 @@ struct Config {
   pub targets: Option<Browsers>,
   pub minify: Option<bool>,
   pub source_map: Option<bool>,
+  pub input_source_map: Option<String>,
   pub drafts: Option<Drafts>,
   pub css_modules: Option<CssModulesOption>,
   pub analyze_dependencies: Option<bool>,
@@ -289,6 +290,12 @@ fn compile<'i>(code: &'i str, config: &Config) -> Result<TransformResult, Compil
   })?;
 
   let map = if let Some(mut source_map) = source_map {
+    if let Some(input_source_map) = &config.input_source_map {
+      if let Ok(mut sm) = SourceMap::from_json("/", input_source_map) {
+        let _ = source_map.extends(&mut sm);
+      }
+    }
+
     source_map.to_json(None).ok()
   } else {
     None

test.js

@@ -30,30 +30,44 @@ if (process.argv[process.argv.length - 1] !== __filename) {
 
 let res = css.transform({
   filename: __filename,
-  minify: false,
+  minify: true,
+  sourceMap: true,
   targets: {
     safari: 4 << 16,
     firefox: 3 << 16 | 5 << 8,
     opera: 10 << 16 | 5 << 8
   },
-  code: Buffer.from(`
-  .foo {
-    color: pink;
+  code: Buffer.from(`.imported {
+    content: "yay, file support!";
   }
-
-  .bar {
-    color: red;
+  
+  .selector {
+    margin: 1em;
+    background-color: #f60;
+  }
+  
+  .selector .nested {
+    margin: 0.5em;
   }
 `),
-  drafts: {
-    // nesting: true
-  },
-  cssModules: {
-    pattern: '[name]-[hash]-[local]'
-  },
-  // analyzeDependencies: true
+  inputSourceMap: JSON.stringify({
+    "version": 3,
+    "sourceRoot": "root",
+    "file": "stdout",
+    "sources": [
+      "stdin",
+      "sass/_variables.scss",
+      "sass/_demo.scss"
+    ],
+    "sourcesContent": [
+      "@import \"_variables\";\n@import \"_demo\";\n\n.selector {\n  margin: $size;\n  background-color: $brandColor;\n\n  .nested {\n    margin: $size / 2;\n  }\n}",
+      "$brandColor: #f60;\n$size: 1em;",
+      ".imported {\n  content: \"yay, file support!\";\n}"
+    ],
+    "mappings": "AEAA,SAAS,CAAC;EACR,OAAO,EAAE,oBAAqB;CAC/B;;AFCD,SAAS,CAAC;EACR,MAAM,ECHD,GAAG;EDIR,gBAAgB,ECLL,IAAI;CDUhB;;AAPD,SAAS,CAIP,OAAO,CAAC;EACN,MAAM,ECPH,KAAG;CDQP",
+    "names": []
+  }),
 });
 
 console.log(res.code.toString());
-console.log(res.exports);
-console.log(require('util').inspect(res.dependencies, { colors: true, depth: 50 }));
+console.log(res.map.toString())