trivial-expression

An expression always gives the same answer, or hands back one of its inputs.

Group

Code

Runs

On by default

Level

warning

Reads

Every file

Fix

--fix fixes it: replaces the expression with its answer where the parts it drops run no effects

Why

Part of this expression does nothing: whatever its inputs, the expression evaluates to a constant or to one of its own parts, as x * 1 is x and x - x is 0. Replace it with its answer, or fix the operand that was meant. Each finding lists the language assumptions the simplification relied on.

The fix, as Ur suggests it: replace it with its answer, or fix the operand that was meant.

For agents

Write no operation or conditional whose result is a constant or one of its own operands, such as x * 1 or a if c else a.

def line_total(price: int, quantity: int) -> int:
    return price * 1 * quantity

$ ur lint --rule trivial-expression
warning[trivial-expression]: `price * 1` is always `price`
  --> ./app/orders.py:2:12 expression in `line_total`
  = assumes: trusted-annotations
  = hint: replace it with its answer, or fix the operand that was meant; `--fix` does this
0 clone classes and 1 trivial expression in 1 file