Struct rslint_core::groups::errors::NoCondAssign

pub struct NoCondAssign {
    pub allow_parens: bool,
}

Forbid the use of assignment expressions in conditions which may yield unwanted behavior.

Assignment expressions return the value assigned:

let foo = 5;

console.log(foo = 8); // 8
console.log(foo += 4) // foo + 4 (12 in this case)

Users often make a typo and end up using = instead of == or === in conditions in statements like if, while, do_while, and for. This is erroneous and is most likely unwanted behavior since the condition used will actually be the value assigned.

Incorrect Code Examples

let foo = 5;

if (foo = 6) {
//      ^^^ assignments return the value assigned, therefore the condition checks `6`
//          `6` is always truthy, therefore the if statement always runs even if we dont want it to.

} else {}
//^^^^ it makes this else unreachable

foo // 6

Fields

allow_parens: bool

Allow an assignment if they are enclosed in parentheses to allow things like reassigning a variable.

Implementations

impl NoCondAssign

pub fn new() -> Self

Trait Implementations

impl Clone for NoCondAssign

fn clone(&self) -> NoCondAssign

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl CstRule for NoCondAssign

fn check_node(&self, node: &SyntaxNode, ctx: &mut RuleCtx) -> Option<()>

Check an individual node in the syntax tree. You can use the match_ast macro to make matching a node to an ast node easier. The reason this uses nodes and not a visitor is because nodes are more flexible, converting them to an AST node has zero cost and you can easily traverse surrounding nodes. Defaults to doing nothing.

fn check_token(&self, token: &SyntaxToken, ctx: &mut RuleCtx) -> Option<()>

Check an individual token in the syntax tree. Defaults to doing nothing.

fn check_root(&self, root: &SyntaxNode, ctx: &mut RuleCtx) -> Option<()>

Check the root of the tree one time. This method is guaranteed to only be called once. The root's kind will be either SCRIPT or MODULE. Defaults to doing nothing.

impl Debug for NoCondAssign

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for NoCondAssign

fn default() -> Self

Returns the "default value" for a type.

impl<'de> Deserialize<'de> for NoCondAssign where
    NoCondAssign: Default, 

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl Rule for NoCondAssign

fn name(&self) -> &'static str

A unique, kebab-case name for the rule.

fn group(&self) -> &'static str

The name of the group this rule belongs to.

impl Serialize for NoCondAssign

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.