Merge pull request #875 from parcel-bundler/sourcemap-improvements

Uglify Sourcemap improvements
parcel-bundler · Feb 21, 2018 · 59436cd · 59436cd
2 parents c25f9bc + c51f834
commit 59436cd
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Showing 2 changed files with 34 additions and 10 deletions.
diff --git a/src/SourceMap.js b/src/SourceMap.js
@@ -200,8 +200,8 @@ class SourceMap {
     let middleIndex = Math.floor((stopIndex + startIndex) / 2);
 
     while (
-      this.mappings[middleIndex][key].line !== line &&
-      startIndex < stopIndex
+      startIndex < stopIndex &&
+      this.mappings[middleIndex][key].line !== line
     ) {
       if (line < this.mappings[middleIndex][key].line) {
         stopIndex = middleIndex - 1;
@@ -211,8 +211,9 @@ class SourceMap {
       middleIndex = Math.floor((stopIndex + startIndex) / 2);
     }
 
-    if (this.mappings[middleIndex][key].line !== line) {
-      return middleIndex;
+    let mapping = this.mappings[middleIndex];
+    if (!mapping || mapping[key].line !== line) {
+      return this.mappings.length - 1;
     }
 
     while (
@@ -221,13 +222,15 @@ class SourceMap {
     ) {
       middleIndex--;
     }
+
     while (
       middleIndex < this.mappings.length - 1 &&
       this.mappings[middleIndex + 1][key].line === line &&
       column > this.mappings[middleIndex][key].column
     ) {
       middleIndex++;
     }
+
     return middleIndex;
   }
 

diff --git a/src/transforms/uglify.js b/src/transforms/uglify.js
@@ -12,10 +12,32 @@ module.exports = async function(asset) {
     warnings: true,
     mangle: {
       toplevel: true
-    },
-    sourceMap: asset.options.sourceMaps ? {filename: asset.relativeName} : false
+    }
   };
 
+  let sourceMap;
+  if (asset.options.sourceMap) {
+    sourceMap = new SourceMap();
+    options.output = {
+      source_map: {
+        add(source, gen_line, gen_col, orig_line, orig_col, name) {
+          sourceMap.addMapping({
+            source,
+            name,
+            original: {
+              line: orig_line,
+              column: orig_col
+            },
+            generated: {
+              line: gen_line,
+              column: gen_col
+            }
+          });
+        }
+      }
+    };
+  }
+
   if (customConfig) {
     options = Object.assign(options, customConfig);
   }
@@ -26,15 +48,14 @@ module.exports = async function(asset) {
     throw result.error;
   }
 
-  if (result.map) {
-    result.map = await new SourceMap().addMap(JSON.parse(result.map));
+  if (sourceMap) {
     if (asset.sourceMap) {
       asset.sourceMap = await new SourceMap().extendSourceMap(
         asset.sourceMap,
-        result.map
+        sourceMap
       );
     } else {
-      asset.sourceMap = result.map;
+      asset.sourceMap = sourceMap;
     }
   }