fix: handle esbuild warnings

Author: alexander-akait

src/utils.js

@@ -158,9 +158,41 @@ async function esbuildMinify(input, sourceMap, minimizerOptions) {
     code: result.code,
     // eslint-disable-next-line no-undefined
     map: result.map ? result.map : undefined,
-    warnings: result.warnings
-      ? result.warnings.map((item) => item.toString())
-      : [],
+    warnings:
+      result.warnings.length > 0
+        ? result.warnings.map((item) => {
+            return {
+              source: item.location && item.location.file,
+              line: item.location && item.location.line,
+              column: item.location && item.location.column,
+              plugin: item.pluginName,
+              message: `${item.text}${
+                item.detail ? `\nDetails:\n${item.detail}` : ""
+              }${
+                item.notes.length > 0
+                  ? `\n\nNotes:\n${item.notes
+                      .map(
+                        (note) =>
+                          `${
+                            note.location
+                              ? `[${note.location.file}:${note.location.line}:${note.location.column}] `
+                              : ""
+                          }${note.text}${
+                            note.location
+                              ? `\nSuggestion: ${note.location.suggestion}`
+                              : ""
+                          }${
+                            note.location
+                              ? `\nLine text:\n${note.location.lineText}\n`
+                              : ""
+                          }`
+                      )
+                      .join("\n")}`
+                  : ""
+              }`,
+            };
+          })
+        : [],
   };
 }
 

test/__snapshots__/minify-option.test.js.snap

@@ -224,6 +224,24 @@ exports[`"minify" option should work with "CssMinimizerPlugin.cssoMinify" minifi
 
 exports[`"minify" option should work with "CssMinimizerPlugin.cssoMinify" minifier: warning 1`] = `Array []`;
 
+exports[`"minify" option should work with "CssMinimizerPlugin.esbuildMinify" minifier and emit warnings: assets 1`] = `
+Object {
+  "foo.css": "width: calc(100px + 100){}
+",
+}
+`;
+
+exports[`"minify" option should work with "CssMinimizerPlugin.esbuildMinify" minifier and emit warnings: error 1`] = `Array []`;
+
+exports[`"minify" option should work with "CssMinimizerPlugin.esbuildMinify" minifier and emit warnings: warning 1`] = `
+Array [
+  "Warning: foo.css from Css Minimizer plugin
+Expected identifier but found whitespace",
+  "Warning: foo.css from Css Minimizer plugin
+Unexpected \\"calc(\\"",
+]
+`;
+
 exports[`"minify" option should work with "CssMinimizerPlugin.esbuildMinify" minifier and generate source maps: assets 1`] = `
 Object {
   "foo.css": "body{color:red}a{color:#00f}

test/fixtures/wrong-calc.css

@@ -0,0 +1 @@
+width: calc(100px + 100);

test/minify-option.test.js

@@ -503,6 +503,37 @@ describe('"minify" option', () => {
     expect(getWarnings(stats)).toMatchSnapshot("warning");
   });
 
+  it('should work with "CssMinimizerPlugin.esbuildMinify" minifier and emit warnings', async () => {
+    const compiler = getCompiler({
+      entry: {
+        foo: `${__dirname}/fixtures/wrong-calc.css`,
+      },
+      module: {
+        rules: [
+          {
+            test: /.s?css$/i,
+            use: [
+              MiniCssExtractPlugin.loader,
+              { loader: "css-loader", options: { sourceMap: true } },
+            ],
+          },
+        ],
+      },
+    });
+
+    new CssMinimizerPlugin({
+      minify: CssMinimizerPlugin.esbuildMinify,
+    }).apply(compiler);
+
+    const stats = await compile(compiler);
+
+    expect(readAssets(compiler, stats, /\.css(\.map)?$/)).toMatchSnapshot(
+      "assets"
+    );
+    expect(getErrors(stats)).toMatchSnapshot("error");
+    expect(getWarnings(stats)).toMatchSnapshot("warning");
+  });
+
   it('should work with "CssMinimizerPlugin.esbuildMinify" minifier and generate source maps', async () => {
     const compiler = getCompiler({
       devtool: "source-map",