JavaScript

The v-bind directive is invalid when: - The directive does not have an attribute value.

It is considered a best practice to avoid 'polluting' the global scope with variables that are intended to be local to the script. Global variables created from a script can produce name collisions with global variables created from another script, which will usually lead to runtime errors or unexpected behavior. It is mostly useful for browser scripts.

In JavaScript, you can extend any object, including builtin or "native" objects. Sometimes people change the behavior of these native objects in ways that break the assumptions made about them in other parts of the code.

It is required to have a return value for every render method. A render function returns a virtual DOM node, commonly named VNode in the Vue ecosystem, which is an interface that allows Vue to write these objects in your browser DOM. They contain all the information necessary to work with Vue.

The following pattern:

Using promises is forbidden in places where the TypeScript compiler allows them but they are not handled properly. These situations can often arise due to a missing await keyword or just a misunderstanding of the way async functions are handled/awaited.

Single-file components should always order <script>, <template>, and <style> tags consistently, with <style> last. At least one of the other two is always necessary.

By default, parent scope attribute bindings that are not recognized as props will "fallthrough". This means that when we have a single-root component, these bindings will be applied to the root element of the child component as normal HTML attributes. When authoring a component that wraps a target element or another component, this may not always be the desired behavior.

Using literals like true, 0, and false on either side of a logical operator is unnecessary. For example, true && something will always evaluate to something.

'^([A-Z][a-z0-9]*)+Type$$' is the default pattern for type alias names.

React components use JSX, not HTML. So we need to use JSX attributes and React replicate the respective HTML property/attribute while rendering. Use of HTML property in JSX can sometimes lead to errors. For example, class is a keyword in JavaScript (JSX is an extension of JavaScript), so it will throw an error. However, in HTML it is a valid attribute.

Note: If you use React with Web Components, use the class attribute instead.

__proto__ property has been deprecated as of ECMAScript 3.1 and shouldn't be used. Use Object.getPrototypeOf and Object.setPrototypeOf instead.

When an argument is omitted from a function call, it will default to undefined. It is therefore redundant to explicitly pass an undefined literal as the last argument.

this.$scopedSlots members should not have more than 2 arguments. - Multiple Arguments create inconsistency.

Located potential errors resulting from misspellings of variable and parameter names, or accidental implicit globals.

Nesting JSX elements too deeply can confuse developers reading the code. To make maintenance and refactoring easier, DeepSource recommends limiting the maximum JSX tree depth to 4.

This rule prevents passing of props to elements. This rule only applies to DOM Nodes (e.g. <div />) and not Components (e.g. <Component />). The list of forbidden props can be customized with the forbid option.

Multiple non-null assertion operators (!s) are redundant, and may confuse the reader. Moreover, foo?.bar should always be preferred over foo!?.bar.

Ensures that any component or prop methods used to handle events are correctly prefixed.