Optimise searching for placeholders - #1370
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Mocking the init method is messy because then the code in the real `__init__` method doesn’t get run, so properties like `content` don’t get set. We can still test the same thing (which arguments the `Field` is instantiated with) by mocking the whole class. Then any downstream code which is looking at the field will be dealing with a mock, which returns something for properties like `content` which don’t exist.
If a string doesn’t have an opening parentheses then we can guarantee it doesn’t have any placeholders in it. We can take advantage of this to skip the expensive regex search. Benchmark for string with no placeholders: ```shell python -m timeit -s "import random; import string; from notifications_utils.field import Field; s = ''.join(random.choices(string.ascii_uppercase + string.digits + string.whitespace, k=1000))" "Field(s).placeholders" ``` Before > 50000 loops, best of 5: 7.68 usec per loop After > 500000 loops, best of 5: 536 nsec per loop 14× faster Benchmark for same string with one placeholder right at the end: ```shell python -m timeit -s "import random; import string; from notifications_utils.field import Field; s = ''.join(random.choices(string.ascii_uppercase + string.digits + string.whitespace, k=1000)) + '((name))'" "Field(s).placeholders" ``` Before > 50000 loops, best of 5: 9.06 usec per loop After > 50000 loops, best of 5: 9.06 usec per loop No change.
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BlessedDev
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If a string doesn’t have an opening parentheses then we can guarantee it doesn’t have any placeholders in it.
We can take advantage of this to skip the expensive regex search.
Benchmark for string with no placeholders
Before
After
14× faster
Benchmark for same string with one placeholder right at the end
Before
After
No change.