test: postcss emit error

Author: cap-Bernardito

test/CssMinimizerPlugin.test.js

@@ -256,6 +256,38 @@ describe('CssMinimizerPlugin', () => {
     });
   });
 
+  it('should throw error from postcss', () => {
+    const compiler = getCompiler({
+      entry: {
+        foo: `${__dirname}/fixtures/test/foo.css`,
+      },
+    });
+
+    new CssMinimizerPlugin({
+      minify: (data) => {
+        // eslint-disable-next-line global-require
+        const postcss = require('postcss');
+
+        const plugin = postcss.plugin('error-plugin', () => (css) => {
+          css.walkDecls((decl) => {
+            throw decl.error('Postcss error');
+          });
+        });
+
+        return postcss([plugin])
+          .process(data.input, data.postcssOptions)
+          .then((result) => {
+            return result;
+          });
+      },
+    }).apply(compiler);
+
+    return compile(compiler).then((stats) => {
+      expect(getErrors(stats)).toMatchSnapshot('error');
+      expect(getWarnings(stats)).toMatchSnapshot('warning');
+    });
+  });
+
   it('should build warning', () => {
     const compiler = getCompiler({
       entry: {

test/__snapshots__/CssMinimizerPlugin.test.js.snap.webpack4

@@ -59,6 +59,15 @@ exports[`CssMinimizerPlugin should respect the hash options #1: errors 1`] = `Ar
 
 exports[`CssMinimizerPlugin should respect the hash options #1: warnings 1`] = `Array []`;
 
+exports[`CssMinimizerPlugin should throw error from postcss: error 1`] = `
+Array [
+  "Error: foo.css from Css Minimizer 
+error-plugin: /foo.css:2:3: Postcss error [foo.css:2,3]",
+]
+`;
+
+exports[`CssMinimizerPlugin should throw error from postcss: warning 1`] = `Array []`;
+
 exports[`CssMinimizerPlugin should work and show minimized assets in stats: assets 1`] = `
 Object {
   "foo.css": "body{color:red}a{color:#00f}",

test/__snapshots__/CssMinimizerPlugin.test.js.snap.webpack5

@@ -59,6 +59,15 @@ exports[`CssMinimizerPlugin should respect the hash options #1: errors 1`] = `Ar
 
 exports[`CssMinimizerPlugin should respect the hash options #1: warnings 1`] = `Array []`;
 
+exports[`CssMinimizerPlugin should throw error from postcss: error 1`] = `
+Array [
+  "Error: foo.css from Css Minimizer 
+error-plugin: /foo.css:2:3: Postcss error [foo.css:2,3]",
+]
+`;
+
+exports[`CssMinimizerPlugin should throw error from postcss: warning 1`] = `Array []`;
+
 exports[`CssMinimizerPlugin should work and generate real content hash: assets 1`] = `
 Object {
   "entry.19e4764f9c1d9fe130e2.2d6ce991710d63180e35.87eaf84ce322e15b3c17.css": "body{color:red}a{color:#00f}",