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if-else-block-instead-of-dict-get (SIM401)

Added in v0.0.219 · Related issues · View source

Derived from the flake8-simplify linter.

Fix is sometimes available.

What it does

Checks for if statements that can be replaced with dict.get calls.

Why is this bad?

dict.get() calls can be used to replace if statements that assign a value to a variable in both branches, falling back to a default value if the key is not found. When possible, using dict.get is more concise and more idiomatic.

Under preview mode, this rule will also suggest replacing if-else expressions with dict.get calls.

Example

foo = {}
if "bar" in foo:
    value = foo["bar"]
else:
    value = 0

Use instead:

foo = {}
value = foo.get("bar", 0)

If preview mode is enabled:

value = foo["bar"] if "bar" in foo else 0

Use instead:

value = foo.get("bar", 0)

References