@angular-eslint/eslint-plugin-template

What is @angular-eslint/eslint-plugin-template?

The @angular-eslint/eslint-plugin-template package is an ESLint plugin that provides linting rules for Angular templates. It helps developers to follow best practices and avoid common mistakes in their Angular template syntax by analyzing the templates and providing feedback.

What are @angular-eslint/eslint-plugin-template's main functionalities?

Banana in a box

This rule ensures that you are using the correct syntax for two-way data binding in Angular templates. The correct syntax is [(ngModel)], and the rule will report an error if it finds something like [ngModel] or (ngModel) instead.

"[(ngModel)]": "off"

Conditional complexity

This rule allows you to specify the maximum complexity that any *ngIf structural directive should have in your templates. It helps in maintaining readability and manageability of the template logic.

"template/conditional-complexity": ["error", { "maxComplexity": 5 }]"

Mouse events have key events

This rule ensures that mouse events like (click) are accompanied by corresponding keyboard events like (keyup) to maintain accessibility for users who rely on keyboard navigation.

"template/mouse-events-have-key-events": "error"

No any

This rule warns you when you use the 'any' type in your templates. Using 'any' can potentially bypass compile-time type checking, so it's generally a good practice to avoid it.

"template/no-any": "warn"

No autocompletion

This rule checks for the use of the 'autofocus' attribute in the template and reports it as an error. Autofocus can cause accessibility issues for users who rely on assistive technologies.

"template/no-autofocus": "error"

Other packages similar to @angular-eslint/eslint-plugin-template

eslint-plugin-react

This package provides linting rules for React and JSX. It is similar to @angular-eslint/eslint-plugin-template in that it helps enforce best practices and catch common mistakes in React applications.

eslint-plugin-vue

This package is an ESLint plugin for Vue.js applications. It includes a set of rules that apply to Vue templates, similar to how @angular-eslint/eslint-plugin-template applies rules to Angular templates.

eslint-plugin-jsx-a11y

This plugin focuses on enforcing accessibility rules in JSX elements, similar to how @angular-eslint/eslint-plugin-template enforces accessibility rules in Angular templates.

README

@angular-eslint/eslint-plugin-template

Please see https://github.com/angular-eslint/angular-eslint for full usage instructions and guidance.

Premade configs

• Premade configs

Rules

Possible problems

Key

• :white_check_mark: = recommended
• :wrench: = fixable
• :bulb: = has suggestions
• :accessibility: = included in accessibility preset

Rule	Description	:white_check_mark:	:wrench:	:bulb:	:accessibility:
no-duplicate-attributes	Ensures that there are no duplicate input properties or output event listeners			:bulb:

Suggestions

Key

• :white_check_mark: = recommended
• :wrench: = fixable
• :bulb: = has suggestions
• :accessibility: = included in accessibility preset

Rule	Description	:white_check_mark:	:wrench:	:bulb:	:accessibility:
alt-text	[Accessibility] Enforces alternate text for elements which require the alt, aria-label, aria-labelledby attributes.				:accessibility:
banana-in-box	Ensures that the two-way data binding syntax is correct	:white_check_mark:	:wrench:
button-has-type	Ensures that a button has a valid type specified
click-events-have-key-events	[Accessibility] Ensures that the click event is accompanied with at least one key event keyup, keydown or keypress.				:accessibility:
conditional-complexity	The conditional complexity should not exceed a rational limit
cyclomatic-complexity	Checks cyclomatic complexity against a specified limit. It is a quantitative measure of the number of linearly independent paths through a program's source code
elements-content	[Accessibility] Ensures that the heading, anchor and button elements have content in it				:accessibility:
eqeqeq	Requires === and !== in place of == and !=	:white_check_mark:	:wrench:	:bulb:
i18n	Ensures following best practices for i18n. Checks for missing i18n attributes on elements and attributes containing texts. Can also check for texts without i18n attribute, elements that do not use custom ID (@@) feature and duplicate custom IDs		:wrench:	:bulb:
interactive-supports-focus	[Accessibility] Ensures that elements with interactive handlers like (click) are focusable.				:accessibility:
label-has-associated-control	[Accessibility] Ensures that a label element/component is associated with a form element				:accessibility:
mouse-events-have-key-events	[Accessibility] Ensures that the mouse events mouseout and mouseover are accompanied by focus and blur events respectively. Coding for the keyboard is important for users with physical disabilities who cannot use a mouse, AT compatibility, and screenreader users. See more at https://www.w3.org/WAI/WCAG21/Understanding/keyboard				:accessibility:
no-any	The use of "$any" nullifies the compile-time benefits of Angular's type system			:bulb:
no-autofocus	[Accessibility] Ensures that the autofocus attribute is not used		:wrench:		:accessibility:
no-call-expression	Disallows calling expressions in templates, except for output handlers
no-distracting-elements	[Accessibility] Enforces that no distracting elements are used		:wrench:		:accessibility:
no-inline-styles	Disallows the use of inline styles in HTML templates
no-interpolation-in-attributes	Ensures that property-binding is used instead of interpolation in attributes.
no-negated-async	Ensures that async pipe results, as well as values used with the async pipe, are not negated	:white_check_mark:		:bulb:
no-positive-tabindex	Ensures that the tabindex attribute is not positive			:bulb:
prefer-control-flow	Ensures that the built-in control flow is used.
prefer-ngsrc	Ensures ngSrc is used instead of src for img elements
role-has-required-aria	[Accessibility] Ensures elements with ARIA roles have all required properties for that role.			:bulb:	:accessibility:
table-scope	[Accessibility] Ensures that the scope attribute is only used on the <th> element		:wrench:		:accessibility:
use-track-by-function	Ensures trackBy function is used
valid-aria	[Accessibility] Ensures that correct ARIA attributes and respective values are used			:bulb:	:accessibility:

Layout

Key

• :white_check_mark: = recommended
• :wrench: = fixable
• :bulb: = has suggestions
• :accessibility: = included in accessibility preset

Rule	Description	:white_check_mark:	:wrench:	:bulb:	:accessibility:
attributes-order	Ensures that HTML attributes and Angular bindings are sorted based on an expected order		:wrench:
prefer-self-closing-tags	Ensures that self-closing tags are used for elements with a closing tag but no content.		:wrench: