The Rules

• Overview
• Regex
  • Example
  • Negation
  • Using multiple regex rules
  • Using multiple regex rules with regex alternation
  • Directory substitutions
• Exists

Overview

ls-lint provides multiple rules out of the box:

Rule	Alias	Description
lowercase	-	Every letter must be lowercase Ignore non letters
camelcase	camelCase	String must be camelCase Only letters and digits allowed
pascalcase	PascalCase	String must be Pascalcase Only letters and digits allowed
snakecase	snake_case	String must be snake*case Only lowercase letters, digits and * allowed
screamingsnakecase	SCREAMING_SNAKE_CASE	String must be snake*case Only uppercase letters, digits and * allowed
kebabcase	kebab-case	String must be kebab-case Only lowercase letters, digits and - allowed
regex	-	Matches regex pattern: ^{pattern}$
exists	-	Allow or disallow the existence of N or N-M files. Also works for directories.

Regex

The regex rule provides full flexibility for your configuration and matches your file and directory names by the ^{pattern}$ pattern

Example

.ls-lint.yml

ls:
  .js: regex:[a-z0-9]+ # the final regex pattern will be ^[a-z0-9]+$

Negation

You can negate the regex rule by adding a ! prefix

.ls-lint.yml

ls:
  .js: regex:![0-9]+ # the final regex pattern will be ^[0-9]+$

Using multiple regex rules

Multiple regex rules are supported by the | operator

.ls-lint.yml

ls:
  .js: regex:Schema(\_test)? | regex:Resolver(\_test)?

Using multiple regex rules with regex alternation (opens new window)

With regex alternation, you can simplify the above example

ls:
  .js: regex:(Schema|Resolver)(\_test)?

Directory substitutions

The regex rule exposes the directory tree as substitution variables that can be referenced in the regex pattern. For instance, you can use ${0} to substitute the parent directory, ${1} for the parent parent, and so on.

Directory tree

components
└── button
    ├── button.ts
    └── tests
        └── button.test.ts

.ls-lint.yml

ls:
  components/*: # e.g.: components/button
    .ts: regex:${0} # e.g.: components/button/button.ts
    .*.scss: regex:${0} # e.g.: components/button/button.module.scss

    tests:
      .test.ts: regex:${1} # e.g.: components/button/tests/button.test.ts

Exists

Allow or disallow N or N-M files for a given extension. The exists rule only applies to the directory itself, not to subdirectories.

Imagine you want to restrict all component directories to only having one .ts and one .test.ts file:

ls:
  components/*:
    .dir: kebab-case
    .*: exists:0
    .ts: kebab-case | exists:1
    .test.ts: kebab-case | exists:1

exists also works for directories:

ls:
  components/{auth,account}:
    dir: exists:1
    .*: ...

    "*":
      .dir: exists:0 # no subdirectories allowed

and ranges:

ls:
  .js: exists:1-10