Shnippet is a versatile code snippet extraction tool designed to help you manage and organize code snippets from your source files, particularly your test suites. It allows you to use your written tests as source code for content that gets surfaced in documentation.
- Leverage Test Suites: Use your existing tests as the source for documentation snippets.
- Customizable Snippet Extraction: Define custom tags to mark the start and end of code snippets.
- Multi-Language Support: Works with various programming languages by specifying file extensions.
- Flexible Output Structure: Choose how your snippets are organized in the output directory.
- Prepend Blocks: Include import statements or other code that should precede your snippets.
- CLI Integration: Use the command-line interface for easy integration into your build process.
Install Shnippet as a dev dependency in your project:
npm install --save-dev shnippet
Or with pnpm:
pnpm add -D shnippet
Create a shnippet.config.ts file in the root directory of your project:
export const config = {
rootDirectory: "./src", // Directory containing source files
snippetOutputDirectory: "./snippets", // Directory to store extracted snippets
fileExtensions: [".js", ".ts", ".kt", ".gradle", ".xml", ".bash", ".swift"], // Supported file types
exclude: ["excludeThisSnippet"], // Snippets to exclude
snippetTags: {
start: ":snippet-start:",
end: ":snippet-end:",
prependStart: ":prepend-start:",
prependEnd: ":prepend-end:",
},
outputDirectoryStructure: "byLanguage", // How snippets are organized
version: "1.0.0", // Versioning for output directories
};Mark the code you want to extract using the custom snippet tags defined in your configuration. By placing these tags in your test suites, you can directly extract code examples from your tests.
// :snippet-start: exampleTestSnippet
test("should greet the user", () => {
const name = "Alice";
const greeting = greet(name);
expect(greeting).toBe("Hello, Alice!");
});
// :snippet-end:Include code that should be prepended to your snippets, such as import statements.
// :prepend-start: exampleTestSnippet
import { greet } from "../src/greet";
// :prepend-end:Use the Shnippet CLI to extract snippets based on your configuration.
Add a script to your package.json:
"scripts": {
"shnippet": "shnippet --config ./shnippet.config.ts"
}Then run:
npm run shnippet
Or with pnpm:
pnpm shnippet
Shnippet provides several command-line options for additional control.
Remove all extracted snippets.
npm run shnippet -- clear
Choose how snippets are organized (flat, match, organized, byLanguage).
npm run shnippet -- --structure byLanguage
Shnippet provides clear error messages for common issues when extracting snippets. Here are the main error cases and how to handle them:
If a snippet is missing its end tag, Shnippet will throw an error with a descriptive message:
Error: Missing end tag for snippet 'example' in file example.js
If a snippet start tag is missing its name, Shnippet will throw an error:
Error: Missing snippet name in file example.js
Here's an example of the correct format for snippets:
// Correct format
//:snippet-start: hello-world
function hello() {
console.log("Hello, world!");
}
//:snippet-end:
// Incorrect formats that will cause errors:
//:snippet-start: // Missing name
function hello() {
console.log("Hello, world!");
}
//:snippet-end:
//:snippet-start: hello-world
function hello() {
console.log("Hello, world!");
} // Missing end tagrootDirectory: Root directory containing the source files (e.g., your test suites).snippetOutputDirectory: Directory where snippets will be saved.fileExtensions: Array of file extensions to process.exclude: Array of snippet names to exclude from extraction.snippetTags: Custom tags to identify snippet boundaries.start: Tag indicating the start of a snippet.end: Tag indicating the end of a snippet.prependStart: Tag indicating the start of a prepend block.prependEnd: Tag indicating the end of a prepend block.
outputDirectoryStructure: Determines how snippets are organized in the output directory.version: Version identifier used in the output directory path.
flat: All snippets are placed in a single directory.match: Snippets mirror the directory structure of the source files.organized: Snippets are organized based on custom logic.byLanguage: Snippets are grouped by programming language (default).
Test File (tests/greet.test.ts):
// :prepend-start: greetTest
import { greet } from "../src/greet";
// :prepend-end:
// :snippet-start: greetTest
test("should greet the user", () => {
const name = "Bob";
const greeting = greet(name);
expect(greeting).toBe("Hello, Bob!");
});
// :snippet-end:Extract Snippets:
npm run shnippet
Use Extracted Snippet in Documentation:
The extracted snippets will be available in your snippets directory, organized by language. For example:
snippets/
1.0.0/
typescript/
greetTest.snippet.txt
If you encounter an error regarding the virtual store location, reinstall your dependencies:
pnpm install
Alternatively, specify the virtual store directory in your .npmrc file:
virtual-store-dir = "node_modules/.pnpm"
The snippet manager is a utility for fetching and displaying code snippets in your frontend application. It handles caching, language-specific formatting, and imports.
import { snippetManager } from '@shnippet/core';
// Get a snippet in a specific language
const pythonCode = await snippetManager.getSnippet('my-snippet', 'python');
// Get display info (available languages and imports)
const info = snippetManager.getSnippetDisplayInfo('my-snippet');
// Returns: {
// languages: ['python', 'kotlin'],
// defaultLanguage: 'python',
// imports: { python: ['from typing import Any'] }
// }Note You probably will never need to configure snippetManager, it's just available for edge-cases.
You can configure the snippet manager to match your needs. This allows you to overwrite your original snippet config settings.
snippetManager.updateConfig({
// Base URL for fetching snippets
baseUrl: 'http://your-snippet-server.com/snippets',
// Languages to support
supportedLanguages: ['python', 'kotlin', 'typescript'],
// Default imports for each language
defaultImports: {
python: ['from typing import Any'],
kotlin: ['import java.util.*'],
typescript: ['import { useState } from "react"']
}
});The snippet manager will cache the results, making subsequent fetches instant.