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mock-keyword-in-code

Category: Mock Data
Severity: Info (in strings) / Warning (in identifiers)
Triggered by: pyscn check --select mockdata

What it does

Flags identifiers and string literals that contain common placeholder keywords: mock, fake, dummy, test, sample, example, placeholder, stub, fixture, temp, foo, bar, baz, lorem, ipsum.

Why is this a problem?

These words are what you type while you're still figuring something out. They're fine in a notebook, a test file, or a five-minute spike — but when one survives into production it usually means a stub was never replaced. The name foo in a checked-in module is almost never what the author meant to ship.

Matches in identifiers are treated as warnings because a bound name (foo = get_user()) changes behaviour. Matches in string literals are info-level because a leftover "fake_user" is more often cosmetic than broken — but still worth reviewing before a release.

Example

def create_user():
    name = "fake_user"    # string literal matches
    foo = get_user()      # identifier `foo` matches
    return foo

Use instead

Remove the placeholder. Use real data, read from configuration, or move the stub into a test fixture where it belongs.

def create_user(name: str):
    user = get_user(name)
    return user

Options

Option Default Description
mock_data.enabled false Opt-in; the whole category is off by default.
mock_data.keywords (built-in list) Override the keyword list for this rule.
mock_data.min_severity "info" "warning" keeps only identifier matches.
mock_data.ignore_tests true Skip files that look like tests.
mock_data.ignore_patterns [] Regex patterns matched against file paths; matches are suppressed.

References