fix: conflict multiple asset error (#194)

* fix: conflict multiple asset error

* fix: modify to work well in mode:'none'

* test: add contenthash-multiple-entries test code

* fix: remove change, cleanup test, upgrade webpack version

Author: unchai

test/cases/contenthash-multiple-entries/entryA.js

@@ -0,0 +1,2 @@
+import "./styleA.css";
+import "./styleB.css";

test/cases/contenthash-multiple-entries/entryB.js

@@ -0,0 +1 @@
+import "./styleA.css";

test/cases/contenthash-multiple-entries/entryC.js

@@ -0,0 +1,2 @@
+import "./styleA.css";
+import "./styleB.css";

test/cases/contenthash-multiple-entries/entryD.js

@@ -0,0 +1,2 @@
+import "./styleC.css";
+import "./styleD.css";

test/cases/contenthash-multiple-entries/entryE.js

@@ -0,0 +1,4 @@
+.styleA { background: red; }
+
+.styleB { background: blue; }
+

test/cases/contenthash-multiple-entries/expected/651d2818ea64cfe50dbe.css

@@ -0,0 +1,4 @@
+.styleA { background: red; }
+
+.styleB { background: blue; }
+

test/cases/contenthash-multiple-entries/expected/7bb844e9f5514d392e40.css

@@ -0,0 +1,2 @@
+.styleA { background: red; }
+

test/cases/contenthash-multiple-entries/expected/f36605fe5d863d4c4785.css

@@ -0,0 +1 @@
+.styleA { background: red; }

test/cases/contenthash-multiple-entries/styleA.css

@@ -0,0 +1 @@
+.styleB { background: blue; }

test/cases/contenthash-multiple-entries/styleB.css

@@ -0,0 +1 @@
+.styleA { background: red; }

test/cases/contenthash-multiple-entries/styleC.css

@@ -0,0 +1 @@
+.styleB { background: blue; }

test/cases/contenthash-multiple-entries/styleD.css

@@ -0,0 +1,30 @@
+const Self = require('../../../');
+
+module.exports = {
+  entry: {
+    'entryA': './entryA.js',
+    'entryB': './entryB.js',
+    'entryC': './entryC.js',
+    'entryD': './entryD.js',
+    'entryE': './entryE.js',
+  },
+  module: {
+    rules: [
+      {
+        test: /\.css$/,
+        use: [
+          Self.loader,
+          'css-loader',
+        ],
+      },
+    ],
+  },
+  output: {
+    filename: '[name]-[contenthash].js',
+  },
+  plugins: [
+    new Self({
+      filename: '[contenthash].css',
+    }),
+  ],
+};