GitHub - microsoft/tslint-microsoft-contrib: A set of TSLint rules used on some Microsoft projects. (original) (raw)
chai-prefer-contains-to-index-of
Avoid Chai assertions that invoke indexOf and compare for a -1 result. It is better to use the chai .contain() assertion API instead because the failure message will be clearer if the test fails.
2.0.10
chai-vague-errors
Avoid Chai assertions that result in vague errors. For example, asserting expect(something).to.be.true
will result in the failure message "Expected true received false". This is a vague error message that does not reveal the underlying problem. It is especially vague in TypeScript because stack trace line numbers often do not match the source code. A better pattern to follow is the xUnit Patterns Assertion Message pattern. The previous code sample could be better written as expect(something).to.equal(true, 'expected something to have occurred');
1.0
detect-child-process
Detects usages of child_process and especially child_process.exec() with a non-literal first argument. It is dangerous to pass a string constructed at runtime as the first argument to the child_process.exec()
.child_process.exec(cmd)
runs cmd
as a shell command which could allow an attacker to execute malicious code injected into cmd
. Instead of child_process.exec(cmd)
you should use child_process.spawn(cmd)
or specify the command as a literal, e.g. child_process.exec('ls')
.
6.2.0-beta
export-name
The name of the exported module must match the filename of the source file. This is case-insensitive by default but ignores file extension. It can be configured to be case-insensitive or to allow names matching a regex. For example, to allow names that differ only in case and an exported name like myChartOptions, then configure the rule like this: "export-name": [true, { "ignore-case": true, "allow": ["myChartOptions"] }]
. You can also just give a list of allowed names, like "export-name": [true, "myChartOptions"]
.
0.0.3
function-name
Applies a naming convention to function names and method names. You can configure the naming convention by passing parameters. Please note, the private-method-regex does take precedence over the static-method-regex, so a private static method must match the private-method-regex. The default values are: [ true, { "method-regex": "^[a-z][\\w\\d]+$", "private-method-regex": "^[a-z][\\w\\d]+$", "protected-method-regex": "^[a-z][\\w\\d]+$", "static-method-regex": "^[A-Z_\\d]+$", "function-regex": "^[a-z][\\w\\d]+$" } ]
This rule has some overlap with the [tslint variable-name rule](https://palantir.github.io/tslint/rules/variable-name/); however, the rule here is more configurable.
2.0.7, 2.0.14
import-name
The name of the imported module must match the name of the thing being imported. For special characters (-
, .
, _
) remove them and make the following character uppercase. For example, it is valid to name imported modules the same as the module name: import Service = require('x/y/z/Service')
and import Service from 'x/y/z/Service'
. But it is invalid to change the name being imported, such as: import MyCoolService = require('x/y/z/Service')
and import MyCoolService from 'x/y/z/Service'
. When containing special characters such as import <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow></mrow><annotation encoding="application/x-tex"></annotation></semantics></math></span><span class="katex-html" aria-hidden="true"></span></span> from 'my-awesome_library';
the corresponding configuration would look like 'import-name': [true, { 'myAwesomeLibrary': '$$' }]
. Since version 2.0.9 it is possible to configure this rule with a list of exceptions. For example, to allow underscore
to be imported as _
, add this configuration: 'import-name': [ true, { 'underscore': '_' }]
2.0.5
informative-docs
Enforces that comments do more than just reiterate names of objects. Either be informative with comments or don't include a comment. You can override the default list of "useless" words ignored by the comment checker like "informative-docs": [true, { "useless-words": ["a", "an", "the", "text" ] } ]
. You can indicate words as synonyms (aliases) of each other like "informative-docs": [true, { "aliases": { text: ["emoji", "smiley"] } ]
.
6.0.0-beta
insecure-random
Do not use insecure sources for random bytes. Use a secure random number generator instead. Bans all uses of Math.random
and crypto.pseudoRandomBytes
. Better alternatives are crypto.randomBytes
and window.crypto.getRandomValues
.
References:
- CWE 330
- MDN Math.random
- Node.js crypto.randomBytes()
window.crypto.getRandomValues()
2.0.11
jquery-deferred-must-complete
When a JQuery Deferred instance is created, then either reject()
or resolve()
must be called on it within all code branches in the scope. For more examples see the feature request.
1.0
max-func-body-length
Avoid long functions. The line count of a function body must not exceed the value configured within this rule's options.
You can set up a general max function body length applied for every function/method/arrow function e.g. [true, 30]
or set different maximum length for every type e.g. [true, { "func-body-length": 10 , "func-expression-body-length": 10 , "arrow-body-length": 5, "method-body-length": 15, "ctor-body-length": 5 }]
. To specify a function name whose parameters you can ignore for this rule, pass a regular expression as a string(this can be useful for Mocha users to ignore the describe()
function). Since version 2.0.9, you can also ignore single- and multi-line comments from the total function length, eg. [true, `{ "ignore-comments": true }]`.
2.0.3
missing-jsdoc
Deprecated - This rule can be replaced with TSLint's file-header
rule. All files must have a top level [JSDoc](http://usejsdoc.org/) comment. A JSDoc comment starts with /** (not one more or one less asterisk) and a JSDoc at the 'top-level' appears without leading spaces. Trailing spaces are acceptable but not recommended
1.0
missing-optional-annotation
Deprecated - This rule is now enforced by the TypeScript compiler. A parameter that follows one or more parameters marked as optional is not itself marked optional.
0.0.1
mocha-avoid-only
Do not invoke Mocha's describe.only
, it.only
, or context.only
functions. These functions are useful ways to run a single unit test or a single test case during your build, but please be careful to not push these methods calls to your version control repository because it will turn off any of the other tests.
1.0
mocha-no-side-effect-code
All test logic in a Mocha test case should be within Mocha lifecycle method and not defined statically to execute when the module loads. Put all assignments and initialization statements in a before()
, beforeEach()
, beforeAll()
, after()
, afterEach()
, afterAll()
, or it()
function. Code executed outside of these lifecycle methods can throw exceptions before the test runner is initialized and can result in errors or even test runner crashes. This rule can be configured with a regex to ignore certain initializations. For example, to ignore any calls to RestDataFactory
configure the rule with: [true, { ignore: '^RestDataFactory\\..*' }]
2.0.10
mocha-unneeded-done
A function declares a MochaDone parameter but only resolves it synchronously in the main function. The MochaDone parameter can be safely removed from the parameter list.
2.0.10
no-backbone-get-set-outside-model
Avoid using model.get('x')
and model.set('x', value)
Backbone accessors outside of the owning model. This breaks type safety and you should define getters and setters for your attributes instead.
1.0
no-banned-terms
Do not use banned terms:
- caller
- callee
- eval
- arguments These terms refer to functions or properties that should not be used, so it is best practice to simply avoid them.
0.0.1
no-constant-condition
Do not use constant expressions in conditions. Similar to the [ESLint no-constant-condition](https://eslint.org/docs/rules/no-constant-condition) rule. Since version 2.0.14, this rule accepts a parameter called checkLoops
which defaults to true. If set to false then loops are not checked for conditionals. For example, disable loop checking with [ true, { 'checkLoops': false } ]
.
1.0, 2.0.14
no-control-regex
Do not use control characters in regular expressions . Similar to the [ESLint no-control-regex](https://eslint.org/docs/rules/no-control-regex) rule
1.0
no-cookies
Do not use cookies.
0.0.1
no-delete-expression
Do not delete expressions. Only properties should be deleted.
0.0.2
no-disable-auto-sanitization
Do not disable auto-sanitization of HTML because this opens up your page to an XSS attack. Specifically, do not use the execUnsafeLocalFunction or setInnerHTMLUnsafe functions.
0.0.1
no-document-domain
Do not write to document.domain
. Scripts setting document.domain to any value should be validated to ensure that the value is on a list of allowed sites. Also, if your site deals with PII in any way then document.domain must not be set to a top-level domain (for example, live.com) but only to an appropriate subdomain (for example, billing.live.com). If you are absolutely sure that you want to set document.domain then add a tslint suppression comment for the line. For more information see the [Phase 4 Verification page of the Microsoft SDL](https://msdn.microsoft.com/en-us/library/cc307418.aspx).
2.0.3
no-document-write
Do not use document.write
0.0.1
no-duplicate-case
Deprecated - This rule can be replaced with TSLint's no-duplicate-switch-case. Do not use duplicate case labels in switch statements. Similar to the ESLint no-duplicate-case rule.
1.0
no-duplicate-parameter-names
Deprecated - This rule is now enforced by the TypeScript compiler. Do not write functions or methods with duplicate parameter names.
0.0.1
no-empty-interfaces
Deprecated - This rule can be replaced with TSLint's no-empty-interface. Do not use empty interfaces. They are compile-time only artifacts and they serve no useful purpose.
1.0
no-empty-line-after-opening-brace
Avoid an empty line after an opening brace.
2.0.6
no-exec-script
Do not use the execScript functions
0.0.1
no-for-in
Avoid use of for-in statements. They can be replaced by Object.keys.
1.0
no-function-constructor-with-string-args
Deprecated - This rule is in the TSLint product as function-constructor
. Do not use the version of the Function constructor that accepts a string argument to define the body of the function.
0.0.1
no-function-expression
Do not use function expressions; use arrow functions (lambdas) instead. In general, lambdas are simpler to use and avoid the confusion about what the 'this' references points to. Function expressions that contain a 'this' reference are allowed and will not create a failure.
1.0
no-http-string
Do not use strings that start with 'http:'. URL strings should start with 'https:'. Http strings can be a security problem and indicator that your software may suffer from cookie-stealing attacks. Since version 1.0, this rule takes a list of regular expressions as a parameter. Any string matching that regular expression will be ignored. For example, to allow http connections to example.com and examples.com, configure your rule like this: "no-http-string": [true, "http://www.example.com/?.*", "http://www.examples.com/?.*"]
.
0.0.3
no-increment-decrement
Deprecated - This rule is in the TSLint product as increment-decrement
. Avoid use of increment and decrement operators particularly as part of complicated expressions.
0.0.1
no-inner-html
Do not write values to innerHTML, outerHTML, or set HTML using the JQuery html() function. Writing values to innerHTML can expose your website to XSS injection attacks. All strings must be escaped before being rendered to the page.
2.0.4
no-invalid-regexp
Do not use invalid regular expression strings in the RegExp constructor. Similar to the ESLint no-invalid-regexp rule.
1.0
no-jquery-raw-elements
Do not create HTML elements using JQuery and string concatenation. It is error prone and can hide subtle defects. Instead use the JQuery element API.
2.0.8
no-missing-visibility-modifiers
Deprecated - This rule is in the TSLint product as member-access
. Class members (both fields and methods) should have visibility modifiers specified. The Principle of Least Visibility guides us to prefer private methods and fields when possible. If a developer forgets to add a modifier then TypeScript assumes the element should be public, which is the wrong default choice.
1.0
no-multiline-string
Do not declare multiline strings
0.0.1
no-multiple-var-decl
Deprecated - This rule is now part of the base TSLint product as the rule named 'one-variable-per-declaration'. Do not use comma separated variable declarations.
1.0
no-octal-literal
Do not use octal literals or escaped octal sequences.
0.0.1
no-regex-spaces
Do not use multiple spaces in a regular expression literal. Similar to the ESLint no-regex-spaces rule.
1.0
no-relative-imports
Do not use relative paths when importing external modules or ES6 import declarations. The advantages of removing all relative paths from imports is that:
- The import name will be consistent across all files and subdirectories so searching for usages is much easier.
- Moving source files to different folders will not require you to edit your import statements.
- It will be possible to copy and paste import lines between files regardless of the file location.
- version control diffs will be simplified by having overall fewer edits to the import lines.
Option
allow-siblings
can be passed to allow relative imports for files in the same or nested folders.
Note: we don't often recommend this rule. See #435 for discussion.
- version control diffs will be simplified by having overall fewer edits to the import lines.
Option
2.0.5
no-reserved-keywords
Deprecated - This rule can be replaced with TSLint's variable-name. Do not use reserved keywords as names of local variables, fields, functions, or other identifiers. Since version 2.0.9 this rule accepts a parameter called allow-quoted-properties
. If true, interface properties in quotes will be ignored. This can be a useful way to avoid verbose suppress-warning comments for generated d.ts files.
This rule has some overlap with the tslint variable-name rule; however, the rule here finds more keywords and more usages.
0.0.1, 2.0.9
no-single-line-block-comment
Avoid single line block comments and use single line comments instead. Block comments do not nest properly and have no advantages over normal single-line comments.
2.0.10
no-stateless-class
Deprecated - This rule can be replaced with TSLint's no-unnecessary-class. A stateless class represents a failure in the object oriented design of the system. A class without state is better modeled as a module or given some state. A stateless class is defined as a class with only static members and no parent class.
2.0.4
no-string-based-set-immediate
Do not use the version of setImmediate that accepts code as a string argument. However, it is acceptable to use the version of setImmediate where a direct reference to a function is provided as the callback argument.
0.0.1
no-string-based-set-interval
Do not use the version of setInterval that accepts code as a string argument. However, it is acceptable to use the version of setInterval where a direct reference to a function is provided as the callback argument.
0.0.1
no-string-based-set-timeout
Do not use the version of setTimeout that accepts code as a string argument. However, it is acceptable to use the version of setTimeout where a direct reference to a function is provided as the callback argument.
0.0.1
no-suspicious-comment
Do not use suspicious comments, such as BUG, HACK, FIXME, LATER, LATER2, TODO. We recommend that you run this rule before each release as a quality checkpoint. Reference: CWE-546 Suspicious Comment.
2.0.11
no-typeof-undefined
Do not use the idiom typeof x === 'undefined'
. You can safely use the simpler x === undefined
or perhaps x == null
if you want to check for either null or undefined.
2.0.8
no-unexternalized-strings
Ensures that double quoted strings are passed to a localize call to provide proper strings for different locales. The rule can be configured using an object literal as documented in the feature request.
2.0.1
no-unnecessary-bind
Deprecated - This rule is in the TSLint product as unnecessary-bind
. Do not bind 'this' as the context for a function literal or lambda expression. If you bind 'this' as the context to a function literal, then you should just use a lambda without the bind. If you bind 'this' as the context to a lambda, then you can remove the bind call because 'this' is already the context for lambdas. Works for Underscore methods as well.
1.0
no-unnecessary-field-initialization
Do not unnecessarily initialize the fields of a class to values they already have. For example, there is no need to explicitly set a field to undefined
in the field's initialization or in the class' constructor. Also, if a field is initialized to a constant value (null, a string, a boolean, or some number) then there is no need to reassign the field to this value within the class constructor.
2.0.9
no-unnecessary-local-variable
Do not declare a variable only to return it from the function on the next line. It is always less code to simply return the expression that initializes the variable.
2.0.4
no-unnecessary-override
Do not write a method that only calls super() on the parent method with the same arguments. You can safely remove methods like this and Javascript will correctly dispatch the method to the parent object.
2.0.4
no-unnecessary-semicolons
Remove unnecessary semicolons.
0.0.1
no-unsupported-browser-code
Avoid writing browser-specific code for unsupported browser versions. Browser versions are specified in the rule configuration options, eg: [true, [ "IE 11", "Firefox > 40", "Chrome >= 45" ] ]
. Browser-specific blocks of code can then be designated with a single-line comment, like so: // Browser specific: IE 10
, or with a jsdoc like this: @browserspecific chrome 40
.
2.0.10
no-useless-files
Avoid keeping files around that only contain commented out code, are completely empty, or only contain whitespace characters.
4.0.2
no-var-self
Deprecated - This rule can be replaced with TSLint's no-this-assignment. Do not use var self = this
; instead, manage scope with arrow functions/lambdas. Self variables are a common practice in JavaScript but can be avoided in TypeScript. By default the rule bans any assignments of the this
reference. If you want to enforce a naming convention or allow some usages then configure the rule with a regex. By default the rule is configured with (?!)
which matches nothing. You can pass ^self$
to allow variables named self or pass ^(?!self$)
to allow anything other than self, for example.
2.0.8
no-with-statement
Do not use with
statements. Assign the item to a new variable instead.
0.0.1
non-literal-fs-path
Detect fs
function calls with a non literal filepath. For security reasons, it may be best to only pass string literals as filesystem paths. Otherwise, it may be possible for an attacker to read and write arbitrary files on your system through path traversal attacks.
6.0.0-beta
non-literal-require
Detect require()
function calls for something that is not a string literal. For security reasons, it may be best to only require()
string literals. Otherwise, it may be possible for an attacker to somehow change the value and download arbitrary Javascript into your page.
2.0.14
possible-timing-attack
Avoid timing attacks by not making direct string comparisons to sensitive data. Do not compare against variables named password, secret, api, apiKey, token, auth, pass, or hash. For more info see [Using Node.js Event Loop for Timing Attacks](https://snyk.io/blog/node-js-timing-attack-ccc-ctf).
2.0.11
prefer-array-literal
Use array literal syntax when declaring or instantiating array types. For example, prefer the Javascript form of string[]
to the TypeScript form Array<string>
. Prefer []
over new Array()
. Prefer [4, 5]
over new Array(4, 5)
. Prefer [undefined, undefined]
over new Array(2)
.
Since 2.0.10, this rule can be configured to allow Array
type parameters. To ignore type parameters, configure the rule with the values: [true, {"allow-type-parameters": true}]
.
Since 6.2.0-beta, you can lift restriction on Array
constructor calls with a single argument (to create empty array of a given length). If type information is available - rule will allow only a single argument of number
type. To allow empty array creation, configure the rule with the values: [true, {"allow-size-argument": true}]
.
This rule has some overlap with the TSLint array-type rule; however, the version here catches more instances.
1.0, 2.0.10, 6.2.0-beta
prefer-type-cast
Prefer the tradition type casts instead of the new 'as-cast' syntax. For example, prefer <string>myVariable
instead of myVariable as string`` . Rule ignores any file ending in .tsx. If you prefer the opposite and want to see the `as` type casts, then enable the tslint rule named 'no-angle-bracket-type-assertion'. ``
2.0.4
promise-must-complete
When a Promise instance is created, then either the reject() or resolve() parameter must be called on it within all code branches in the scope. For more examples see the feature request.
This rule has some overlap with the tslint no-floating-promises rule, but they are substantially different.
1.0
react-a11y-accessible-headings
For accessibility of your website, there should be no more than 2 H1 heading elements, HTML heading elements must be concise, used for structuring information on the page and non-empty.
6.0.0
react-a11y-anchors
For accessibility of your website, anchor element link text should be at least 4 characters long. Links with the same HREF should have the same link text. Links that point to different HREFs should have different link text. This can be relaxed to allow differences in cases using ignore-case
option. You can also allow differences in leading/trailing whitespace by adding {"ignore-whitespace": "trim"}
option or all whitespace by adding {"ignore-whitespace": "all"}
option. Links with images and text content, the alt attribute should be unique to the text content or empty. An an anchor element's href prop value must not be undefined, null, or just #.
References:
- WCAG Rule 38: Link text should be as least four 4 characters long
- WCAG Rule 39: Links with the same HREF should have the same link text
- WCAG Rule 41: Links that point to different HREFs should have different link text
- WCAG Rule 43: Links with images and text content, the alt attribute should be unique to the text content or empty
2.0.11
react-a11y-aria-unsupported-elements
For accessibility of your website, enforce that elements that do not support ARIA roles, states, and properties do not have those attributes.
2.0.11
react-a11y-event-has-role
For accessibility of your website, elements with event handlers must have explicit role or implicit role.
References:
2.0.11
react-a11y-iframes
Enforce that iframe elements are not empty, have title, and are unique.
6.1.0
react-a11y-image-button-has-alt
For accessibility of your website, enforce that inputs element with type="image"
must have non-empty alt attribute.
2.0.11
react-a11y-img-has-alt
Enforce that an img
element contains the alt
attribute or role='presentation'
for a decorative image. All images must have alt
text to convey their purpose and meaning to screen reader users. Besides, the alt
attribute specifies an alternate text for an image, if the image cannot be displayed.
This rule accepts as a parameter a string array for tag names other than img to also check. For example, if you use a custom tag named 'Image' then configure the rule with: [true, ['Image']]
.
References:
- Web Content Accessibility Guidelines 1.0
- ARIA Presentation Role
- WCAG Rule 31: If an image has an alt or title attribute, it should not have a presentation role
2.0.11
react-a11y-input-elements
For accessibility of your website, HTML input boxes and text areas must include default, place-holding characters.
References:
6.0.0-beta
react-a11y-lang
For accessibility of your website, HTML elements must have a lang attribute and the attribute must be a valid language code.
References:
- H58: Using language attributes to identify changes in the human language
- lang attribute must have a valid value
- List of ISO 639-1 codes
2.0.11
react-a11y-media-captions
Enforce that video and audio elements have captions and descriptions.
@next
react-a11y-meta
For accessibility of your website, HTML meta elements must not have http-equiv="refresh"
.
2.0.11
react-a11y-mouse-event-has-key-event
For accessibility of your website, elements with mouseOver/mouseOut should be accompanied by onFocus/onBlur keyboard events.
6.2.0-beta
react-a11y-no-onchange
For accessibility of your website, enforce usage of onBlur over onChange on select menus. References:
- OnChange Event Accessibility Issues
- Guideline 8. Ensure direct accessibility of embedded user interfaces.
6.0.0-beta
react-a11y-props
For accessibility of your website, enforce all aria-*
attributes are valid. Elements cannot use an invalid aria-*
attribute. This rule will fail if it finds an aria-*
attribute that is not listed in WAI-ARIA states and properties.
2.0.11
react-a11y-proptypes
For accessibility of your website, enforce the type of aria state and property values are correct.
2.0.11
react-a11y-required
For accessibility of your website, enforce that required input elements have aria-required set to true.
References:
6.0.0-beta
react-a11y-role
For accessibility of your website, elements with aria roles must use a **valid**, **non-abstract** aria role. A reference to role definitions can be found at [WAI-ARIA roles](https://www.w3.org/TR/wai-aria-1.1/#role_definitions).
References:
2.0.11
react-a11y-role-has-required-aria-props
For accessibility of your website, elements with aria roles must have all required attributes according to the role.
References:
- ARIA Definition of Roles
- WCAG Rule 90: Required properties and states should be defined
- WCAG Rule 91: Required properties and states must not be empty
2.0.11
react-a11y-role-supports-aria-props
For accessibility of your website, enforce that elements with explicit or implicit roles defined contain only aria-*
properties supported by that role
. Many aria attributes (states and properties) can only be used on elements with particular roles. Some elements have implicit roles, such as <a href='hrefValue' />
, which will be resolved to role='link'
. A reference for the implicit roles can be found at Default Implicit ARIA Semantics.
References:
- ARIA attributes can only be used with certain roles
- Check aria properties and states for valid roles and properties
- Check that 'ARIA-' attributes are valid properties and states
2.0.11
react-a11y-tabindex-no-positive
For accessibility of your website, enforce tabindex value is **not greater than zero**. Avoid positive tabindex attribute values to synchronize the flow of the page with keyboard tab order.
References:
2.0.11
react-a11y-titles
For accessibility of your website, HTML title elements must not be empty, must be more than one word, and must not be more than 60 characters long.
References:
- WCAG 2.0 - Requirement 2.4.2 Page Titled (Level A)
- OAA-Accessibility Rule 13: Title element should not be empty
- OAA-Accessibility Rule 24: Title content should be concise
- OAA-Accessibility Rule 25: Title text must contain more than one word
2.0.11
react-anchor-blank-noopener
For security reasons, anchor tags with target="_blank"
should also include rel="noreferrer"
. In order to restrict the behavior window.opener
access, the original page needs to add a rel="noopener"
attribute to any link that has target="_blank"
. However, Firefox does not support that tag, so you should actually use rel="noopener noreferrer"
for full coverage.
By default, the rule considers the use of rel="noreferrer"
as sufficient. The option 'force-rel-redundancy'
can be passed to require rel="noopener noreferrer"
.
For more info see: The target="_blank" vulnerability by example.
2.0.11
react-iframe-missing-sandbox
React iframes must specify a sandbox attribute. If specified as an empty string, this attribute enables extra restrictions on the content that can appear in the inline frame. The value of the attribute can either be an empty string (all the restrictions are applied), or a space-separated list of tokens that lift particular restrictions. You many not use both allow-scripts and allow-same-origin at the same time, as that allows the embedded document to programmatically remove the sandbox attribute in some scenarios.
2.0.10
react-no-dangerous-html
Do not use React's dangerouslySetInnerHTML API. This rule finds usages of the dangerouslySetInnerHTML API (but not any JSX references). For more info see the react-no-dangerous-html Rule wiki page.
0.0.2
react-this-binding-issue
Several errors can occur when using React and React.Component subclasses. When using React components you must be careful to correctly bind the 'this' reference on any methods that you pass off to child components as callbacks. For example, it is common to define a private method called 'onClick' and then specify onClick={this.onClick}
as a JSX attribute. If you do this then the 'this' reference will be undefined when your private method is invoked. The React documentation suggests that you bind the 'this' reference on all of your methods within the constructor: this.onClick = this.onClick.bind(this);
. This rule will create a violation if:
- a method reference is passed to a JSX attribute without being bound in the constructor
- a method is bound multiple times in the constructor
Another issue that can occur is binding the 'this' reference to a function within the render() method. For example, many people will create an anonymous lambda within the JSX attribute to avoid the 'this' binding issue:
onClick={() => { this.onClick(); }}
. The problem with this is that a new instance of an anonymous function is created every time render() is invoked. When React compares virutual DOM properties within shouldComponentUpdate() then the onClick property will look like a new property and force a re-render. You should avoid this pattern because creating function instances within render methods breaks any logic within shouldComponentUpdate() methods. This rule creates violations if: - an anonymous function is passed as a JSX attribute
- if a function instantiated in local scope is passed as a JSX attribute
This rule can be configured via the "allow-anonymous-listeners" parameter. If you want to suppress violations for the anonymous listener scenarios then configure that rule like this:
"react-this-binding-issue": [ true, { 'allow-anonymous-listeners': true } ]
, you can also pass in array of string which can act as bind method decorators:"react-this-binding-issue": [true, {'bind-decorators': ['autobind']}]
2.0.8, 2.0.9
react-tsx-curly-spacing
Consistently use spaces around the brace characters of JSX attributes. You can either allow or ban spaces between the braces and the values they enclose.
One of the two following options are required:
"always"
enforces a space inside of curly braces (default)"never"
disallows spaces inside of curly braces By default, braces spanning multiple lines are not allowed with either setting. If you want to allow them you can specify an additional allowMultiline property with the value false.
Examples:"react-tsx-curly-spacing": [true, "always"]
"react-tsx-curly-spacing": [true, "never"]
"react-tsx-curly-spacing": [true, "never", {"allowMultiline": false}]
References:- eslint-plugin-react jsx-curly-spacing rule
- tslint-react jsx-curly-spacing rule
2.0.14
react-unused-props-and-state
Remove unneeded properties defined in React Props and State interfaces. Any interface named Props or State is defined as a React interface. All fields in these interfaces must be referenced. This rule can be configured with regexes to match custom Props and State interface names.
Example for including all interfaces ending with Props or State: [ true, { 'props-interface-regex': 'Props$', 'state-interface-regex': 'State$' } ]
.
2.0.10
underscore-consistent-invocation
Enforce a consistent usage of the _ functions. By default, invoking underscore functions should begin with wrapping a variable in an underscore instance: _(list).map(...)
. An alternative is to prefer using the static methods on the _ variable: _.map(list, ...)
. The rule accepts a single parameter called 'style' which can be the value 'static' or 'instance': [true, { "style": "static" }]
.
2.0.10
use-named-parameter
Do not reference the arguments object by numerical index; instead, use a named parameter. This rule is similar to JSLint's Use a named parameter rule.
0.0.3
use-simple-attributes
Simpler attributes in JSX and TSX files helps keep code clean and readable. Separate complex expressions into their own line and use clear variable names to make your code more understandable.
6.0.0
valid-typeof
Deprecated - This rule is now enforced by the TypeScript compiler. Ensures that the results of typeof are compared against a valid string. This rule aims to prevent errors from likely typos by ensuring that when the result of a typeof operation is compared against a string, that the string is a valid value. Similar to the valid-typeof ESLint rule.
1.0
void-zero
void 0
, which resolves to undefined
, can be confusing to newcomers. Exclusively use undefined
to reduce ambiguity.
6.1.0