JAVASCRIPT.md

Javascript Linter Rules

Below is a list of rules we use for our eslint.

this is adapted from documentation here

note: we use "extends": "eslint:recommended" property in our configuration file (read more)

• constructor-super
• jsx-quotes
• jsx-one-expression-per-line
• max-len
• max-statements
• no-case-declarations
• no-class-assign
• no-compare-neg-zero
• no-cond-assign
• no-console
• no-const-assign
• no-constant-condition
• no-control-regex
• no-debugger
• no-delete-var
• no-dupe-args
• no-dupe-class-members
• no-dupe-keys
• no-duplicate-case
• no-empty-character-class
• no-empty-pattern
• no-empty
• no-ex-assign
• no-extra-boolean-cast
• no-extra-semi
• no-fallthrough
• no-func-assign
• no-global-assign
• no-inner-declarations
• no-invalid-regexp
• no-irregular-whitespace
• no-mixed-spaces-and-tabs
• no-new-symbol
• no-obj-calls
• no-octal
• no-redeclare
• no-regex-spaces
• no-self-assign
• no-sparse-arrays
• no-this-before-super
• no-undef
• no-unexpected-multiline
• no-unreachable
• no-unsafe-finally
• no-unsafe-negation
• no-unused-labels
• no-unused-vars
• no-useless-escape
• no-var
• react/display-name
• react/forbid-prop-types
• react/jsx-curly-spacing
• react/jsx-key
• react/jsx-no-duplicate-props
• react/jsx-no-undef
• react/jsx-pascal-case
• react/jsx-uses-react
• react/jsx-uses-vars
• react/no-danger
• react/no-did-mount-set-state
• react/no-did-update-set-state
• react/no-direct-mutation-state
• react/no-multi-comp
• react/no-unknown-property
• react/prefer-es6-class
• react/prop-types
• react/react-in-jsx-scope
• react/self-closing-comp
• react/sort-comp
• require-yield
• semi
• use-isnan
• valid-typeof

no-compare-neg-zero

• disallow comparing against -0 read more

no-cond-assign

• disallow assignment operators in conditional expressions read more

no-console

• disallow the use of console read more

no-constant-condition

• disallow constant expressions in conditions read more

no-control-regex

• disallow control characters in regular expressions read more

no-debugger

• disallow the use of debugger read more

no-dupe-args

• disallow duplicate arguments in function definitions read more

no-dupe-keys

• disallow duplicate keys in object literals read more

no-duplicate-case

• disallow duplicate case labels read more

no-empty

• disallow empty block statements read more

no-empty-character-class

• disallow empty character classes in regular expressions read more

no-ex-assign

• disallow reassigning exceptions in catch clauses read more

no-extra-boolean-cast

• disallow unnecessary boolean casts read more

no-extra-semi

• disallow unnecessary semicolons read more

no-func-assign

• disallow reassigning function declarations read more

no-inner-declarations

• disallow variable or function declarations in nested blocks read more

no-invalid-regexp

• disallow invalid regular expression strings in RegExp constructors read more

no-irregular-whitespace

• disallow irregular whitespace outside of strings and comments read more

no-obj-calls

• disallow calling global object properties as functions read more

no-regex-spaces

• disallow multiple spaces in regular expressions read more

no-sparse-arrays

• disallow sparse arrays read more

no-unexpected-multiline

• disallow confusing multiline expressions read more

no-unreachable

• disallow unreachable code after return, throw, continue, and break statements read more

no-unsafe-finally

• disallow control flow statements infinallyblocks read more

no-unsafe-negation

• disallow negating the left operand of relational operators read more

use-isnan

• require calls toisNaN() when checking for NaN read more

valid-typeof

• enforce comparing typeof expressions against valid strings read more

no-case-declarations

• disallow lexical declarations in case clauses read more

no-empty-pattern

• disallow empty destructuring patterns read more

no-fallthrough

• disallow fallthrough of case statements read more

no-global-assign

• disallow assignments to native objects or read-only global variables read more

no-octal

• disallow octal literals read more

no-redeclare

• disallow variable redeclaration read more

no-self-assign

• disallow assignments where both sides are exactly the same read more

no-unused-labels

• disallow unused labels read more

no-useless-escape

• disallow unnecessary escape characters read more

no-delete-var

• disallow deleting variables read more

no-undef

• disallow the use of undeclared variables unless mentioned in /*global*/ comments read more

no-unused-vars

• disallow unused variables read more

no-mixed-spaces-and-tabs

• disallow mixed spaces and tabs for indentation read more

constructor-super

• require super() calls in constructors read more

no-class-assign

• disallow reassigning class members read more

no-const-assign

• disallow reassigning const variables read more

no-dupe-class-members

• disallow duplicate class members read more

no-new-symbol

• disallow new operators with the Symbol object read more

no-this-before-super

• disallow this/super before calling super() in constructors read more

require-yield

• require generator functions to contain yield read more

no-var

• require let or const instead of var read more

semi

• require semicolons read more

jsx-quotes

• enforce the consistent use of double quotes in JSX attributes read more

max-len

• enforce a maximum line length read more

max-statements

• enforce a maximum number of statements allowed in function blocks read more

react/display-name

• prevent missing displayName in a React component definition read more

react/forbid-prop-types

• checks all JSX components and verifies that no forbidden propsTypes are used. read more

react/jsx-curly-spacing

• aims to maintain consistency around the spacing inside of JSX attributes and expressions inside element children. read more

react/jsx-key

• warn if an element that likely requires a key prop--namely, one present in an array literal or an arrow function expression. read more

react/jsx-no-duplicate-props

• prevent duplicate properties in JSX read more

react/jsx-no-undef

• disallows undeclared variables in JSX read more

react/jsx-pascal-case

• enforces coding style that user-defined JSX components are defined and referenced in PascalCase. read more

react/jsx-uses-react

• prevent React being incorrectly marked as unused read more

react/jsx-uses-vars

• prevent variables used in JSX to be incorrectly marked as unused read more

react/no-danger

• prevent usage of dangerous JSX properties read more

react/no-did-mount-set-state

• prevent usage of setState in componentDidMount read more

react/no-did-update-set-state

• prevent usage of setState in componentDidUpdate read more

react/no-direct-mutation-state

• prevent direct mutation of this.state read more

react/no-multi-comp

• prevent multiple component definition per file read more

react/no-unknown-property

• prevent usage of unknown DOM property read more

react/prefer-es6-class

• enforce ES6 class for React Components read more

react/prop-types

• prevent missing props validation in a React component definition read more

react/react-in-jsx-scope

• Prevent missing React when using JSX read more

react/self-closing-comp

• prevent extra closing tags for components without children read more

react/sort-comp

• enforce component methods order read more