Fix max length error on conlist with type int

[yohanvalencia]

Change Summary

The list length displayed an incorrect error message when constrained to only integer types

Example Code:

from pydantic_core import SchemaValidator, ValidationError

v = SchemaValidator(
    {
        'type': 'typed-dict',
        'fields': {
            'foo': {
                'type': 'typed-dict-field',
                'schema': {
                    'type': 'list',
                    'max_length': 4,
                    'items_schema': {'type': 'int'},
                },
            },
        },
    }
)

try:
    v.validate_python({'foo': list(range(9))})
except ValidationError as e:
    print(e)

Before: List should have at most 4 items after validation, not 5.
Now: List should have at most 4 items after validation, not 9.

Related issue number

fix pydantic/pydantic#7059

Checklist

• Unit tests for the changes exist
• Documentation reflects the changes where applicable
• Pydantic tests pass with this pydantic-core (except for expected changes)
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

Selected Reviewer: @dmontagu

[codecov]

Codecov Report

Merging #902 (5e139b0) into main (7f7d03d) will increase coverage by 0.05%.
Report is 9 commits behind head on main.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #902      +/-   ##
==========================================
+ Coverage   93.78%   93.84%   +0.05%     
==========================================
  Files         105      105              
  Lines       15331    15459     +128     
  Branches       25       25              
==========================================
+ Hits        14378    14507     +129     
+ Misses        947      946       -1     
  Partials        6        6              

Files Changed	Coverage Δ
src/input/return_enums.rs	85.59% <100.00%> (+0.64%)	⬆️

... and 11 files with indirect coverage changes

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[codspeed-hq]

CodSpeed Performance Report

Merging #902 will not alter performance

_{Comparing yvalencia91:max-length-error-with-type-int (5e139b0) with main (7f7d03d)}

Summary

✅ 138 untouched benchmarks

[yohanvalencia]

Since the actual size of the list is 15 and not 11 I decided to change the values.

[yohanvalencia]

Please review

[adriangb]

I see that this is also happening in #914. I might make a PR to make just this change so we avoid conflicts

[adriangb]

So if it's somethign that has a len (like a list) we use that, if it doesn't have a len we use DEFAULT_CAPACITY. That means that if you feed a generator in you'll end up with an error message that includes whatever DEFAULT_CAPACITY is, right?

[yohanvalencia]

That's right, for the first part but for the generator I realise it wasn't working. The max_length need to be caught by a None condition. So if someone validates this:

from pydantic_core import SchemaValidator


def infinite_generator():
    i = 0
    while True:
        yield i
        i += 1


v = SchemaValidator({'type': 'list'})
v.validate_python(infinite_generator())

Then the error message will be:

Otherwise, this will run into an infinite loop.

[adriangb]

Sorry meant to request changes in the earlier review.

[yohanvalencia]

Please review

[samuelcolvin]

this is a mistake, we need to revert it ASAP.

[davidhewitt]

Improved in #990