Skip to content

fromisoformat-replace-z (FURB162)

Added in 0.12.0 · Related issues · View source

Derived from the refurb linter.

Fix is always available.

What it does

Checks for datetime.fromisoformat() calls where the only argument is an inline replacement of Z with a zero offset timezone.

Why is this bad?

On Python 3.11 and later, datetime.fromisoformat() can handle most ISO 8601 formats including ones affixed with Z, so such an operation is unnecessary.

More information on unsupported formats can be found in the official documentation.

Example

from datetime import datetime


date = "2025-01-01T00:00:00Z"

datetime.fromisoformat(date.replace("Z", "+00:00"))
datetime.fromisoformat(date[:-1] + "-00")
datetime.fromisoformat(date.strip("Z", "-0000"))
datetime.fromisoformat(date.rstrip("Z", "-00:00"))

Use instead:

from datetime import datetime


date = "2025-01-01T00:00:00Z"

datetime.fromisoformat(date)

Fix safety

The fix is always marked as unsafe, as it might change the program's behaviour.

For example, working code might become non-working:

d = "Z2025-01-01T00:00:00Z"  # Note the leading `Z`

datetime.fromisoformat(d.strip("Z") + "+00:00")  # Fine
datetime.fromisoformat(d)  # Runtime error

References