avoid modify cssProcessorOptions.map option (NMFR#19)

ycycwx · NMFR · commit 7917759b407e · 2017-09-13T10:04:12.000+01:00
diff --git a/index.js b/index.js
@@ -52,7 +52,8 @@ OptimizeCssAssetsPlugin.prototype.processCss = function(assetName, asset, assets
             (map.mappings && map.mappings.length > 0)
           )
         ) {
-          processOptions.map.prev = mapJson;
+          var mapOptions = Object.assign({ prev: mapJson }, processOptions.map);
+          processOptions.map = mapOptions;
         }
       }
     } catch (err) {

Original file line number	Diff line number	Diff line change
`@@ -52,7 +52,8 @@ OptimizeCssAssetsPlugin.prototype.processCss = function(assetName, asset, assets`
`52`	`52`	`(map.mappings && map.mappings.length > 0)`
`53`	`53`	`)`
`54`	`54`	`) {`
`55`		`- processOptions.map.prev = mapJson;`
	`55`	`+ var mapOptions = Object.assign({ prev: mapJson }, processOptions.map);`
	`56`	`+ processOptions.map = mapOptions;`
`56`	`57`	`}`
`57`	`58`	`}`
`58`	`59`	`} catch (err) {`