eslint-plugin-mark

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code-lang-shorthand

🔧 Fixable ⭐ CommonMark 🌟 GFM

🔗 Rule Source 🔗 Test Source

Enforce the use of shorthand for code block language identifiers.

Rule Details ​

The purpose of this rule is to enforce the use of shorthand language identifiers in code blocks. Some may want to use abbreviated language identifiers to keep the code blocks concise and consistent.

Using shorthand language identifiers offers several advantages: they improve readability by simplifying code, optimize file size, ensure consistency across code blocks, and make it easier for tools and automation systems to process language identifiers efficiently.

Note that the code block language identifiers are case-insensitive, meaning JavaScript, javascript, and JAVASCRIPT are all treated as the same language identifier.

You can see the full list of language identifiers shorthand mapping in the source code.

Examples ​

❌ Incorrect ​

Examples of incorrect code for this rule:

Default ​

md
```javascript
console.log('Hello, world!');
```

```typescript
console.log('Hello, world!');
```

```markdown
Hello, world!
```
js
export default [
  // ...
  {
    rules: {
      'mark/code-lang-shorthand': 'error', 
    },
  },
  // ...
];

With override: { example: 'ex' } Option ​

md
```example
Welcome to the example language!
```
js
export default [
  // ...
  {
    rules: {
      'mark/code-lang-shorthand': ['error', { 
        override: { example: 'ex' }, 
      }], 
    },
  },
  // ...
];

✅ Correct ​

Examples of correct code for this rule:

Default ​

md
```js
console.log('Hello, world!');
```

```ts
console.log('Hello, world!');
```

```md
Hello, world!
```
js
export default [
  // ...
  {
    rules: {
      'mark/code-lang-shorthand': 'error', 
    },
  },
  // ...
];

With ignores: ['javascript', 'typescript'] Option ​

md
```javascript
console.log('Hello, world!');
```

```typescript
console.log('Hello, world!');
```
js
export default [
  // ...
  {
    rules: {
      'mark/code-lang-shorthand': ['error', { 
        ignores: ['javascript', 'typescript'], 
      }], 
    },
  },
  // ...
];

Options ​

js
'mark/code-lang-shorthand': ['error', {
  ignores: [],
  override: {},
}]

ignores ​

Default: []

An array of code block language identifiers to ignore. Each value should be a lowercase, unabridged language identifier.

For example, to ignore the javascript and typescript language identifiers:

js
'mark/code-lang-shorthand': ['error', {
  ignores: ['javascript', 'typescript'],
}]

override ​

Default: {}

An object where the key is the unabridged language identifier and the value is the abbreviated form.

Adding a new abbreviation ​

For example, to shorten the example language identifier to ex:

js
'mark/code-lang-shorthand': ['error', {
  override: {
    example: 'ex',
  },
}]

Overriding an existing abbreviation ​

For example, to change the default abbreviation for javascript to mjs:

js
'mark/code-lang-shorthand': ['error', {
  override: {
    javascript: 'mjs',
  },
}]

Fix ​

This rule converts unabridged code block language identifiers into their abbreviated forms.

AST ​

This rule applies only to the Code node.