chore: update naming to implementation

README.md

@@ -593,12 +593,14 @@ module.exports = {
 };
 ```
 
-### `customPostcss`
+### `implementation`
 
 Type: `Function`
 Default: `undefined`
 
-A custom `postcss` factory function for the loader to use. **This option is only really useful for downstream tooling authors to ease the PostCSS 7-to-8 transition.**
+The special `implementation` option determines which implementation of PostCSS to use. Overrides the locally installed `peerDependency` version of `postcss`.
+
+**This option is only really useful for downstream tooling authors to ease the PostCSS 7-to-8 transition.**
 
 **webpack.config.js**
 
@@ -613,7 +615,7 @@ module.exports = {
           { loader: "css-loader" },
           {
             loader: "postcss-loader",
-            options: { customPostcss: require("postcss") },
+            options: { implementation: require("postcss") },
           },
           { loader: "sass-loader" },
         ],

src/index.js

@@ -46,7 +46,7 @@ export default async function loader(content, sourceMap, meta) {
       ? true
       : options.postcssOptions.config;
 
-  const postcss = options.customPostcss || ourPostcss;
+  const postcss = options.implementation || ourPostcss;
 
   let loadedConfig;
 

src/options.json

@@ -36,8 +36,8 @@
       "description": "Enables/Disables generation of source maps (https://github.com/postcss/postcss-loader#sourcemap)",
       "type": "boolean"
     },
-    "customPostcss": {
-      "description": "An explicit PostCSS function to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#customPostcss)",
+    "implementation": {
+      "description": "The implementation of postcss to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#implementation)",
       "instanceof": "Function"
     }
   },

test/__snapshots__/customPostcss.test.js.snap → test/__snapshots__/implementation.test.js.snap

@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`"customPostcss" option should work with a custom instance of PostCSS: css 1`] = `
+exports[`"implementation" option should work with a custom instance of PostCSS: css 1`] = `
 "a {
   color: black;
 }
@@ -47,6 +47,6 @@ a {
 "
 `;
 
-exports[`"customPostcss" option should work with a custom instance of PostCSS: errors 1`] = `Array []`;
+exports[`"implementation" option should work with a custom instance of PostCSS: errors 1`] = `Array []`;
 
-exports[`"customPostcss" option should work with a custom instance of PostCSS: warnings 1`] = `Array []`;
+exports[`"implementation" option should work with a custom instance of PostCSS: warnings 1`] = `Array []`;

test/__snapshots__/validate-options.test.js.snap

@@ -1,35 +1,5 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`validate options should throw an error on the "customPostcss" option with "/test/" value 1`] = `
-"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
- - options.customPostcss should be an instance of function.
-   -> An explicit PostCSS function to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#customPostcss)"
-`;
-
-exports[`validate options should throw an error on the "customPostcss" option with "[]" value 1`] = `
-"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
- - options.customPostcss should be an instance of function.
-   -> An explicit PostCSS function to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#customPostcss)"
-`;
-
-exports[`validate options should throw an error on the "customPostcss" option with "{}" value 1`] = `
-"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
- - options.customPostcss should be an instance of function.
-   -> An explicit PostCSS function to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#customPostcss)"
-`;
-
-exports[`validate options should throw an error on the "customPostcss" option with "1" value 1`] = `
-"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
- - options.customPostcss should be an instance of function.
-   -> An explicit PostCSS function to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#customPostcss)"
-`;
-
-exports[`validate options should throw an error on the "customPostcss" option with "something" value 1`] = `
-"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
- - options.customPostcss should be an instance of function.
-   -> An explicit PostCSS function to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#customPostcss)"
-`;
-
 exports[`validate options should throw an error on the "execute" option with "/test/" value 1`] = `
 "Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
  - options.execute should be a boolean.
@@ -66,6 +36,36 @@ exports[`validate options should throw an error on the "execute" option with "te
    -> Enables/Disables PostCSS parser support in 'CSS-in-JS' (https://github.com/postcss/postcss-loader#execute)"
 `;
 
+exports[`validate options should throw an error on the "implementation" option with "/test/" value 1`] = `
+"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
+ - options.implementation should be an instance of function.
+   -> The implementation of postcss to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#implementation)"
+`;
+
+exports[`validate options should throw an error on the "implementation" option with "[]" value 1`] = `
+"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
+ - options.implementation should be an instance of function.
+   -> The implementation of postcss to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#implementation)"
+`;
+
+exports[`validate options should throw an error on the "implementation" option with "{}" value 1`] = `
+"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
+ - options.implementation should be an instance of function.
+   -> The implementation of postcss to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#implementation)"
+`;
+
+exports[`validate options should throw an error on the "implementation" option with "1" value 1`] = `
+"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
+ - options.implementation should be an instance of function.
+   -> The implementation of postcss to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#implementation)"
+`;
+
+exports[`validate options should throw an error on the "implementation" option with "something" value 1`] = `
+"Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
+ - options.implementation should be an instance of function.
+   -> The implementation of postcss to use, instead of the locally installed version (https://github.com/postcss/postcss-loader#implementation)"
+`;
+
 exports[`validate options should throw an error on the "postcssOptions" option with "{"config":[]}" value 1`] = `
 "Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.
  - options.postcssOptions should be one of these:

test/customPostcss.test.js → test/implementation.test.js

@@ -8,12 +8,12 @@ import {
   getWarnings,
 } from "./helpers";
 
-describe('"customPostcss" option', () => {
+describe('"implementation" option', () => {
   it("should work with a custom instance of PostCSS", async () => {
     const spy = jest.fn(postcss);
     const compiler = getCompiler("./css/index.js", {
       // Wrap the spy so it is an instanceof Function
-      customPostcss: (...args) => spy(...args),
+      implementation: (...args) => spy(...args),
     });
     const stats = await compile(compiler);
     const codeFromBundle = getCodeFromBundle("style.css", stats);

test/validate-options.test.js

@@ -50,7 +50,7 @@ describe("validate options", () => {
       success: [true, false],
       failure: [1, /test/, [], {}, "something"],
     },
-    customPostcss: {
+    implementation: {
       success: [require("postcss")],
       failure: [1, /test/, [], {}, "something"],
     },