match with one arm whose pattern only binds a name
ID |
rust.maintainability.match_single_binding |
Severity |
info |
Remediation Complexity |
trivial |
Remediation Risk |
low |
Remediation Effort |
low |
Resource |
Control Flow |
Language |
Rust |
Description
Reports a match with a single arm whose pattern is a plain binding, a _, or a tuple of bindings. Nothing is being discriminated - the arm always runs - so the construct is a let written as control flow.
Rationale
A match tells the reader that a value is being discriminated and that the arms are the alternatives worth considering. When there is one arm and its pattern matches everything, that promise is false: the reader stops to work out which cases are covered, and the body sits one indentation level deeper than it needs to for no gain.
The following code illustrates the pattern detected by this rule:
pub fn binding_arm(x: i32) {
// FLAGGED: match with one arm whose pattern only binds a name
match x {
y => println!("{}", y),
}
}