fix: webpack 3 RuleSet creation (#407)

mzgoddard · Jul 12, 2018 · 6551c8e · 6551c8e
1 parent 3f0b438
commit 6551c8e
Showing 1 changed file with 14 additions and 5 deletions.
diff --git a/lib/util/serial.js b/lib/util/serial.js
@@ -74,11 +74,20 @@ const loaders = (exports.loaders = {
           ruleSet = extra.compiler.__hardSource_ruleSet;
           if (!ruleSet) {
             const RuleSet = require('webpack/lib/RuleSet');
-            ruleSet = extra.compiler.__hardSource_ruleSet = new RuleSet(
-              extra.compiler.options.module.defaultRules.concat(
-                extra.compiler.options.module.rules,
-              ),
-            );
+            if (extra.compiler.options.module.defaultRules) {
+              // webpack 4
+              ruleSet = extra.compiler.__hardSource_ruleSet = new RuleSet(
+                extra.compiler.options.module.defaultRules.concat(
+                  extra.compiler.options.module.rules,
+                ),
+              );
+            } else {
+              // webpack <4
+              ruleSet = extra.compiler.__hardSource_ruleSet = new RuleSet(
+                extra.compiler.options.module.rules ||
+                  extra.compiler.options.module.loaders,
+              );
+            }
           }
         }
         return {