tslint

A linter for the TypeScript language.

Supported Rules

• ban bans the use of specific functions. Options are ["object", "function"] pairs that ban the use of object.function()
• class-name enforces PascalCased class and interface names.
• comment-format enforces rules for single-line comments. Rule options:
  • "check-space" enforces the rule that all single-line comments must begin with a space, as in // comment
  • "check-lowercase" enforces the rule that the first non-whitespace character of a comment must be lowercase, if applicable
• curly enforces braces for if/for/do/while statements.
• eofline enforces the file to end with a newline.
• forin enforces a for ... in statement to be filtered with an if statement.*
• indent enforces consistent indentation levels (currently disabled).
• interface-name enforces the rule that interface names must begin with a capital 'I'
• label-position enforces labels only on sensible statements.
• label-undefined checks that labels are defined before usage.
• max-line-length sets the maximum length of a line.
• no-arg disallows access to arguments.callee.
• no-bitwise disallows bitwise operators.
• no-console disallows access to the specified functions on console. Rule options are functions to ban on the console variable.
• no-consecutive-blank-lines disallows having more than one blank line in a row in a file
• no-construct disallows access to the constructors of String, Number, and Boolean.
• no-debugger disallows debugger statements.
• no-duplicate-key disallows duplicate keys in object literals.
• no-duplicate-variable disallows duplicate variable declarations.
• no-empty disallows empty blocks.
• no-eval disallows eval function invocations.
• no-string-literal disallows object access via string literals.
• no-trailing-whitespace disallows trailing whitespace at the end of a line.
• no-unreachable disallows unreachable code after break, catch, throw, and return statements.
• one-line enforces the specified tokens to be on the same line as the expression preceding it. Rule options:
  • "check-catch" checks that catch is on the same line as the closing brace for try
  • "check-else" checks that else is on the same line as the closing brace for if
  • "check-open-brace" checks that an open brace falls on the same line as its preceding expression.
  • "check-whitespace" checks preceding whitespace for the specified tokens.
• quotemark enforces consistent single or double quoted string literals.
• radix enforces the radix parameter of parseInt
• semicolon enforces semicolons at the end of every statement.
• triple-equals enforces === and !== in favor of == and !=.
• typedef enforces type definitions to exist. Rule options:
  • "callSignature" checks return type of functions
  • "catchClause" checks type in exception catch blocks
  • "indexSignature" checks index type specifier of indexers
  • "parameter" checks type specifier of parameters
  • "propertySignature" checks return types of interface properties
  • "variableDeclarator" checks variable declarations
• typedef-whitespace enforces spacing whitespace for type definitions. Each rule option requires a value of "space" or "nospace" to require a space or no space before the type specifier's colon. Rule options:
  • "callSignature" checks return type of functions
  • "catchClause" checks type in exception catch blocks
  • "indexSignature" checks index type specifier of indexers
• variable-name allows only camelCased or UPPER_CASED variable names. Rule options:
  • "allow-leading-underscore" allows underscores at the beginnning.
• whitespace enforces spacing whitespace. Rule options:
  • "check-branch" checks branching statements (if/else/for/while) are followed by whitespace
  • "check-decl"checks that variable declarations have whitespace around the equals token
  • "check-operator" checks for whitespace around operator tokens
  • "check-separator" checks for whitespace after separator tokens (,/;)
  • "check-type" checks for whitespace before a variable type specification

Installation

CLI

sudo npm install tslint -g

Library

npm install tslint

Usage

Please first ensure that the TypeScript source files compile correctly.

CLI

usage: tslint

Options:
  -c, --config  		 configuration file
  -f, --file    		 file to lint                 [required]
  -o, --out     		 output file
  -r, --rules-dir   	 rules directory
  -s, --formatters-dir   formatters directory
  -t, --format  		 output format (prose, json)  [default: "prose"]

By default, configuration is loaded from .tslintrc or tslint.json, if either exists in the current path.

Library

var options = {
    formatter: "json",
    configuration: configuration,
    rulesDirectory: "customRules/",
    formattersDirectory: "customFormatters/"
};

var Linter = require("tslint");

var ll = new Linter(fileName, contents, options);
var result = ll.lint();

Development

Setup

git clone git@github.com:palantir/tslint.git
cd tslint
git submodule init
git submodule update

Build

npm install
grunt

TODO

• Add more rules from jshint
• Disallow variables referenced outside of their scope definition
• Disallow unused variables
• Support pluggable formatters