docs: enrich README with full API documentation, usage examples, and showcases (#21)

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: SoonIter

README.md

@@ -2,27 +2,47 @@
 
 [![npm latest version](https://img.shields.io/npm/v/path-serializer?style=flat-square&color=98c379)](https://www.npmjs.com/package/path-serializer)
 
-1. stabilize pnpm dependencies path in snapshot
-2. transform win32 path to posix path
-3. escapeEOL \r\n -> \n
-   and more...
+A snapshot serializer that normalizes system-specific paths into stable, readable placeholders — designed for Vitest, Jest, and Rstest.
+
+- Stabilize pnpm dependencies path in snapshot
+- Transform win32 path to posix path
+- Replace absolute paths with placeholders (`<ROOT>`, `<WORKSPACE>`, `<HOME>`, `<TEMP>`)
+- Handle `file://` protocol URLs
+- Escape EOL (`\r\n` -> `\n`)
+- Normalize ANSI color codes
 
 ```ts
 // __snapshots__/index.test.ts.snap
-// 😭 bad
+
+// 😭 Without path-serializer — fragile, platform-specific, unreadable
 {
   "loader" : "D:\\user\\rspack\\node_modules\\.pnpm\\css-loader@6.11.0_@rspack+core@packages+rspack_webpack@5.94.0_@swc+core@1.4.0_@swc+helpers@0._jlcdgjlw2ezzhg43ml3d627wdu\\node_modules\\css-loader\\utils.ts"
 }
-//😎👍🏻 good
+
+// 😎 With path-serializer — stable, cross-platform, clean
 {
   "loader" : "<ROOT>/node_modules/<PNPM_INNER>/css-loader/utils.ts"
 }
 ```
 
+## Installation
+
+```bash
+# npm
+npm install path-serializer -D
+
+# pnpm
+pnpm add path-serializer -D
+```
+
 ## Usage
 
+### Basic
+
 ```typescript
 // vitest.setup.ts
+import path from 'node:path';
+import { expect } from 'vitest';
 import { createSnapshotSerializer } from 'path-serializer';
 
 expect.addSnapshotSerializer(
@@ -32,12 +52,119 @@ expect.addSnapshotSerializer(
 );
 ```
 
-More features can be found in [./src/types.ts](https://github.com/rspack-contrib/path-serializer/blob/main/src/types.ts)
+### With Workspace (Monorepo)
+
+```typescript
+expect.addSnapshotSerializer(
+  createSnapshotSerializer({
+    root: path.join(__dirname, '../..'),
+    workspace: path.join(__dirname, '..'),
+  }),
+);
+```
+
+This replaces:
+- Workspace paths → `<WORKSPACE>/...`
+- Root paths → `<ROOT>/...`
+
+### Custom Replacements
+
+Use `replace` and `replacePost` to add custom path matchers:
+
+```typescript
+expect.addSnapshotSerializer(
+  createSnapshotSerializer({
+    root: path.join(__dirname, '..'),
+    replace: [
+      { match: /port\s\d+/, mark: 'PORT' },
+      { match: '/specific/path', mark: 'CUSTOM' },
+    ],
+  }),
+);
+```
+
+### Hooks
+
+Use `beforeSerialize` and `afterSerialize` for custom pre/post processing:
+
+```typescript
+expect.addSnapshotSerializer(
+  createSnapshotSerializer({
+    root: path.join(__dirname, '..'),
+    beforeSerialize: (val) => val.replace(/hash:\w{8}/g, 'hash:<HASH>'),
+    afterSerialize: (val) => val.trim(),
+  }),
+);
+```
+
+## Options
+
+### `root`
+
+- **Type:** `string`
+- **Default:** `process.cwd()`
+
+Repository root path. Paths under this directory are replaced with `<ROOT>`.
+
+### `workspace`
+
+- **Type:** `string`
+- **Default:** `''`
+
+Workspace root path (for monorepos). Paths under this directory are replaced with `<WORKSPACE>`.
+
+### `replace`
+
+- **Type:** `PathMatcher[]`
+
+Custom matchers applied **before** built-in replacements.
+
+### `replacePost`
+
+- **Type:** `PathMatcher[]`
+
+Custom matchers applied **after** built-in replacements.
+
+### `beforeSerialize`
+
+- **Type:** `(val: string) => string`
+
+Transform the raw string before any replacements.
+
+### `afterSerialize`
+
+- **Type:** `(val: string) => string`
+
+Transform the final string after all replacements.
+
+### `features`
+
+Toggle individual features (all enabled by default):
+
+| Feature | Default | Description |
+|---|---|---|
+| `replaceWorkspace` | `true` | `/foo/packages/core/src` → `<WORKSPACE>/src` |
+| `replaceRoot` | `true` | `/foo/node_modules/.pnpm` → `<ROOT>/node_modules/.pnpm` |
+| `replaceWorkspaceWithFileProtocol` | `true` | `file:///foo/packages/core/src` → `<WORKSPACE>/src` |
+| `replaceRootWithFileProtocol` | `true` | `file:///foo/node_modules/.pnpm` → `<ROOT>/node_modules/.pnpm` |
+| `replacePnpmInner` | `true` | Collapse pnpm's long `.pnpm/...` paths to `<PNPM_INNER>` |
+| `replaceTmpDir` | `true` | `os.tmpdir()` paths → `<TEMP>` |
+| `replaceHomeDir` | `true` | `os.homedir()` paths → `<HOME>` |
+| `transformWin32Path` | `true` | Convert `D:\\foo\\bar` to `/d/foo/bar` |
+| `transformCLR` | `true` | Normalize ANSI color escape codes |
+| `escapeDoubleQuotes` | `true` | Escape `"` to `\"` |
+| `escapeEOL` | `true` | Normalize `\r\n` to `\n` |
+| `addDoubleQuotes` | `true` | Wrap output in double quotes |
+
+More details can be found in [./src/types.ts](https://github.com/rspack-contrib/path-serializer/blob/main/src/types.ts).
 
 ## Showcases
 
-[Rslib](https://github.com/web-infra-dev/rslib/blob/3ff6859eb38171c731e447a1364afc021f8c501a/tests/setupVitestTests.ts)
+- [Rslib](https://github.com/web-infra-dev/rslib/blob/3ff6859eb38171c731e447a1364afc021f8c501a/tests/setupVitestTests.ts)
+- [Rsbuild](https://github.com/web-infra-dev/rsbuild/blob/a50eafa3519caaa66ecd6b0ccb2897a8194781ff/scripts/test-helper/vitest.setup.ts)
+- [Rspack](https://github.com/web-infra-dev/rspack/blob/5a6162c/packages/rspack-test-tools/src/helper/expect/placeholder.ts)
+- [Rspress](https://github.com/web-infra-dev/rspress/blob/8d620050cc2590954838e201d39c10744b6d1bac/scripts/test-helper/rstest.setup.ts)
 
-[Rsbuild](https://github.com/web-infra-dev/rsbuild/blob/a50eafa3519caaa66ecd6b0ccb2897a8194781ff/scripts/test-helper/vitest.setup.ts)
+## License
 
-[Rspack](https://github.com/web-infra-dev/rspack/blob/5a6162c/packages/rspack-test-tools/src/helper/expect/placeholder.ts)
+[MIT](./LICENSE)