test: add test for entry and auto (webpack#1334)

Author: alexander-akait

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

@@ -13412,6 +13412,48 @@ Array [
 
 exports[`"modules" option should work with the "auto" by default for icss: warnings 1`] = `Array []`;
 
+exports[`"modules" option should work with the "auto" by default when CSS file is entrypoint: entry 1`] = `
+"// Imports
+import ___CSS_LOADER_API_IMPORT___ from \\"../../../../src/runtime/api.js\\";
+var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(function(i){return i[1]});
+// Module
+___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n    color: red;\\\\n}\\\\n\\", \\"\\"]);
+// Exports
+export default ___CSS_LOADER_EXPORT___;
+"
+`;
+
+exports[`"modules" option should work with the "auto" by default when CSS file is entrypoint: errors 1`] = `Array []`;
+
+exports[`"modules" option should work with the "auto" by default when CSS file is entrypoint: module 1`] = `
+"// Imports
+import ___CSS_LOADER_API_IMPORT___ from \\"../../../../src/runtime/api.js\\";
+var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(function(i){return i[1]});
+// Module
+___CSS_LOADER_EXPORT___.push([module.id, \\"._wr0eVpMbaGr94MKhByE {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\"]);
+// Exports
+___CSS_LOADER_EXPORT___.locals = {
+	\\"relative\\": \\"_wr0eVpMbaGr94MKhByE\\"
+};
+export default ___CSS_LOADER_EXPORT___;
+"
+`;
+
+exports[`"modules" option should work with the "auto" by default when CSS file is entrypoint: result 1`] = `
+Array [
+  Array [
+    "./modules/mode/relative.module.css",
+    "._wr0eVpMbaGr94MKhByE {
+  color: red;
+}
+",
+    "",
+  ],
+]
+`;
+
+exports[`"modules" option should work with the "auto" by default when CSS file is entrypoint: warnings 1`] = `Array []`;
+
 exports[`"modules" option should work with the "auto" by default with "modules" filename: errors 1`] = `Array []`;
 
 exports[`"modules" option should work with the "auto" by default with "modules" filename: module 1`] = `

test/fixtures/modules/mode/entry.css

@@ -0,0 +1,3 @@
+.class {
+    color: red;
+}

test/helpers/getCompiler.js

@@ -9,7 +9,9 @@ export default (fixture, loaderOptions = {}, config = {}) => {
     target: "node",
     devtool: config.devtool || false,
     context: path.resolve(__dirname, "../fixtures"),
-    entry: path.resolve(__dirname, "../fixtures", fixture),
+    entry: Array.isArray(fixture)
+      ? fixture
+      : path.resolve(__dirname, "../fixtures", fixture),
     output: {
       path: path.resolve(__dirname, "../outputs"),
       filename: "[name].bundle.js",

test/modules-option.test.js

@@ -886,6 +886,26 @@ describe('"modules" option', () => {
     expect(getErrors(stats)).toMatchSnapshot("errors");
   });
 
+  it('should work with the "auto" by default when CSS file is entrypoint', async () => {
+    const compiler = getCompiler([
+      "./modules/mode/entry.css",
+      "./modules/mode/modules.js",
+    ]);
+    const stats = await compile(compiler);
+
+    expect(getModuleSource("./modules/mode/entry.css", stats)).toMatchSnapshot(
+      "entry"
+    );
+    expect(
+      getModuleSource("./modules/mode/relative.module.css", stats)
+    ).toMatchSnapshot("module");
+    expect(getExecutedCode("main.bundle.js", compiler, stats)).toMatchSnapshot(
+      "result"
+    );
+    expect(getWarnings(stats)).toMatchSnapshot("warnings");
+    expect(getErrors(stats)).toMatchSnapshot("errors");
+  });
+
   it('should work with the "auto" by default with "modules" filename', async () => {
     const compiler = getCompiler("./modules/mode/modules-2.js");
     const stats = await compile(compiler);