repeated-argument

A call is given the same value for two parameters.

Group: Tests
Runs: On by default
Level: warning
Reads: Tests
Fix: None: which value to change is the author's choice
Defends: Fidelity: when the code is broken, the test fails.

Why

The test passes one value to two positional parameters of a call, so code that swaps them or reads one twice still passes. Values are compared as values, so 0x10 and 16 are the same. A repeated default such as 0 or "" is left to trivial-inputs.

The fix, as Ur suggests it: give each parameter a different value.

For agents

Give each parameter of a call under test a different value, so a test fails when the code swaps or confuses them.

Example

shop/orders.py

def line_total(quantity, unit_price):
    return quantity * unit_price

tests/test_orders.py

from shop.orders import line_total


def test_line_total():
    assert line_total(4, 4) == 16

What Ur prints

$ ur lint --rule repeated-argument
warning[repeated-argument]: test `test_line_total` passes one value to two parameters, so swapping them goes unnoticed
  --> ./tests/test_orders.py:5:12 test `test_line_total`
  = step 1: ./tests/test_orders.py:5:23 a value
  = step 2: ./tests/test_orders.py:5:26 the same value again
  = hint: give each parameter a different value
  = see: Choosing Values for Robust Tests, Google Testing Blog (2026-06-04), https://testing.googleblog.com/2026/06/choosing-values-for-robust-tests.html
0 clone classes and 1 test finding in 2 files

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Source

Choosing Values for Robust Tests, Google Testing Blog (2026-06-04).