feat: use .css as default extension for test option

README.md

@@ -32,7 +32,7 @@ var style2 = css`
 
 Regular expression or function which test importee for being parsed as style file (css).  
 Type: `RegExp | Function`  
-Default: `() => false`  
+Default: `/\.css$/`  
 Example: `/\.css$/` only `.css` imports will be parsed
 
 #### postcss

src/index.spec.ts

@@ -7,7 +7,7 @@ import plugin, { PluginOptions } from '.';
 function run(source: string, options?: Partial<PluginOptions>, ...plugins_: any[]) {
     const { code } = transform(source, {
         filename: 'test.ts',
-        plugins: [[plugin, { test: /\.css$/, ...(options || {}) }], ...plugins_],
+        plugins: [[plugin, { ...(options || {}) }], ...plugins_],
     })!;
     return code;
 }
@@ -71,7 +71,7 @@ it('side effect import', () => {
     expect(result).toEqual(expect.stringMatching(`import 'style.css';`));
 });
 
-it('unknow file should be touched', () => {
+it('unknow file should not be touched', () => {
     const result = run(
         stripIndents`
         import style from 'style.vue';
@@ -83,6 +83,32 @@ it('unknow file should be touched', () => {
     expect(result).toEqual(expect.stringMatching(`import style from 'style.vue'`));
 });
 
+it('file with matched extension is transformed', () => {
+    const result = run(
+        stripIndents`
+        import style from 'style.pcss';
+        `,
+        {
+            readFileSync: () => 'a {}',
+            test: /\.p?css$/,
+        },
+    );
+    expect(result).toEqual(expect.stringMatching(`const style = "a {}";`));
+});
+
+it('function as test option is executed', () => {
+    const result = run(
+        stripIndents`
+        import style from 'style.pcss';
+        `,
+        {
+            readFileSync: () => 'a {}',
+            test: (file) => file.includes('.pcss'),
+        },
+    );
+    expect(result).toEqual(expect.stringMatching(`const style = "a {}";`));
+});
+
 it('tagged template expression', () => {
     const result = run(
         stripIndents`

src/index.ts

@@ -5,7 +5,7 @@ import { dirname, resolve } from 'path';
 import { getCss } from './getcss';
 
 const defaultOptions = {
-    test: (() => false) as RegExp | Function,
+    test: /\.css$/ as RegExp | Function,
     readFileSync: undefined as Function | undefined,
     postcss: undefined as undefined | string | boolean,
     tagged: undefined as undefined | [string, string],