restricted-filenames.md

Restrict file and path names

Rule Details

In projects in which several developers or even teams work together, it is important that files are not simply stored anywhere. This rule ensures that defined path/file name schemes are adhered to.

Example configuration for this rule:

'restricted-filenames': ['error', {
  basePath: './src',
  allowed: [
    'components/**/index.tsx',
    'utils/{index.ts,lib/[a-z]+([a-zA-Z])?(.spec).ts}'
  ],
  disallowed: [
    'components/NotAllowed/index.tsx'
  ]
}]

Examples of valid file paths:

• components/MyComponent/index.tsx
• utils/index.ts
• utils/lib/myFunction.ts
• utils/lib/myFunction.spec.ts

Examples of invalid file paths:

• components/myComponent/index.tsx
• components/myComponent/index.ts
• components/MyComponent/subfolder/index.tsx
• components/NotAllowed/index.tsx
• utils/index.tsx
• utils/helper.ts
• utils/helper/index.ts
• utils/lib/MyFunction.ts
• utils/lib/my-function.ts
• utils/lib/myFunction.js
• utils/lib/myFunction.test.ts

Priority of allowed and disallowed

If only allowed is set, all unspecified files are disallowed.

If only disallowed is set, all unspecified files are allowed.

If both are set, disallowed wins over allowed and all unspecified files are disallowed.

Useful reusable code snippets in Glob patterns

Name	Example	Glob pattern
Lower case	DONUTS	[a-z]*([a-z0-9])
Upper case	donuts	[A-Z]*([A-Z0-9])
Snake case	number_of_donuts	[a-z]*(*([a-z0-9]-)+([a-z0-9]))
Screaming snake case	NUMBER_OF_DONUTS	[A-Z]*(*([A-Z0-9]_)+([A-Z0-9]))
Kebab case	number-of-donuts	[a-z]*(*([a-z0-9]-)+([a-z0-9]))
Camel case	numberOfDonuts	[a-z]*([a-zA-Z0-9])
Pascal case	NumberOfDonuts	[A-Z]*([a-zA-Z0-9])

Glob pattern templates

Instead of defining the same complex patterns over and over again, e.g. for casing, you can write them into a variable and use them within the pattern, for example by using template strings.

Example of .eslintrc.cjs:

const snippets = {
  lowerCase: '[a-z]*([a-z0-9])',
  upperCase: '[A-Z]*([A-Z0-9])',
  snakeCase: '[a-z]*(*([a-z0-9]_)+([a-z0-9]))',
  screamingSnakeCase: '[A-Z]*(*([A-Z0-9]_)+([A-Z0-9]))',
  kebabCase: '[a-z]*(*([a-z0-9]-)+([a-z0-9]))',
  camelCase: '[a-z]*([a-zA-Z0-9])',
  pascalCase: '[A-Z]*([a-zA-Z0-9])'
};

module.exports = {
  rules: {
    'restricted-filenames': ['error', {
      basePath: './src',
      allowed: [
        `components/${snippets.pascalCase}/index.tsx`,
        `utils/{index.ts,lib/${snippets.camelCase}?(.spec).ts}`
      ]
    }]
  }
};

Further Reading

See Glob Tool - Test globs against sets of test strings quickly and easily online
See micromatch - The used Glob matching library