Support datamodel-code-generator 0.59

[koxudaxi]

Summary

• Update datamodel-code-generator to the latest 0.59 series.
• Handle boolean JSON Schema variants in discriminator object-variant detection.
• Refresh the shadowed-import expected output for the new generated import behavior.

Validation

• uv run pytest
• ./scripts/lint.sh

Summary by CodeRabbit

• Bug Fixes

  • Enhanced discriminator variant processing to correctly handle non-object and boolean schema representations.
  • Updated generated code templates to use direct type references instead of aliases.

• Tests

  • Added test coverage for boolean variant discriminator handling.

• Chores

  • Updated dependencies.

[github-actions]

📚 Docs Preview: https://pr-589.fastapi-code-generator.pages.dev

[coderabbitai]

Walkthrough

The PR updates the parser to handle boolean schemas in discriminator variants, bumps the datamodel-code-generator dependency from 0.56.1 to 0.59, and updates expected test templates to reflect the new behavior. The core change guards _is_object_discriminator_variant against non-object inputs and validates the logic with a new test.

Changes

Boolean Discriminator Variant Support

Layer / File(s)	Summary
Parser boolean discriminator variant logic fastapi_code_generator/parser.py	_is_object_discriminator_variant now accepts JsonSchemaObject | bool input, explicitly returns False for non-object types, and resolves $ref before checking object properties or recursing into allOf.
Parser test for boolean variant discriminator removal tests/test_parser.py	New test verifies that get_field_extras removes the discriminator field when a oneOf variant contains a boolean schema value alongside object schemas.
Dependency update and expected template adjustment pyproject.toml, tests/data/expected/openapi/default_template/shadowed_imports/main.py	datamodel-code-generator[http] updated from 0.56.1 to 0.59; expected test template imports datetime.date directly instead of aliased, and get_actions_ parameter type changes from Optional[date_aliased] to Optional[date].

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• koxudaxi/fastapi-code-generator#566: Parser change to _is_object_discriminator_variant aligns with discriminator-stripping logic for non-object union variants.

Poem

🐰 Schemas once boolean now handled with care,
The parser checks type before object's declare,
Dependencies rise from 0.56 to beyond,
Templates refresh with the new magic wand,
✨ Discriminators dance where they belong.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'Support datamodel-code-generator 0.59' directly aligns with the main objective of upgrading the project to support datamodel-code-generator 0.59 series, which is reflected in all four changed files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch support-datamodel-code-generator-0.59

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[codspeed-hq]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

✅ 1 untouched benchmark

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_{Comparing support-datamodel-code-generator-0.59 (f3405b5) with main (a1e6ae2)}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (a1e6ae2) to head (f3405b5).

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #589   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           17        17           
  Lines         1351      1357    +6     
  Branches       139       140    +1     
=========================================
+ Hits          1351      1357    +6     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@pyproject.toml`:
- Line 31: The dependency bump to datamodel-code-generator (>=0.59,<0.60)
introduces breaking codegen changes; regenerate all generated models (the code
produced by datamodel-code-generator), run snapshot/unit tests, and update any
custom templates to account for the new flags and attributes — specifically
update template logic that relied on field.required to use
field.use_default_with_required where appropriate, adapt templates/consumers of
RootModel/payload changes, remove usages/imports of internal classes
ValidatedDefault and WrappedDefault, handle TypedDict import deduplication, and
adjust dict key handling for patternProperties/propertyNames; after regen, fix
any typing/validation diffs and re-run tests to confirm all snapshots and type
checks pass.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: d8ef0a02-875d-466b-b6f5-3d1af885691e

📥 Commits

Reviewing files that changed from the base of the PR and between a1e6ae2 and f3405b5.

⛔ Files ignored due to path filters (1)

• uv.lock is excluded by !**/*.lock

📒 Files selected for processing (4)

• fastapi_code_generator/parser.py
• pyproject.toml
• tests/data/expected/openapi/default_template/shadowed_imports/main.py
• tests/test_parser.py

[github-actions]

Breaking Change Analysis

Result: Breaking changes detected

Reasoning: The PR contains two breaking changes: (1) Generated code output changed - the shadowed import aliasing behavior from datamodel-code-generator 0.59 now uses direct type references instead of _aliased suffixes, which changes the generated FastAPI code output. This is confirmed by the test expectation change from from datetime import date as date_aliased to from datetime import date. (2) The dependency floor for datamodel-code-generator jumped from 0.56.1 to 0.59, dropping compatibility with three minor versions that users may have been using.

Content for Release Notes

Code Generation Changes

• Shadowed imports no longer use aliases - Generated code that previously aliased conflicting imports (e.g., from datetime import date as date_aliased) now uses the direct type reference (e.g., from datetime import date). Function signatures also change accordingly (e.g., date_aliased → date). Users who regenerate code may see different output, and downstream code referencing aliased names will need updating. (Support datamodel-code-generator 0.59 #589)

Python or Dependency Support Changes

• datamodel-code-generator minimum version raised from 0.56.1 to 0.59 - The required version of datamodel-code-generator[http] changed from >=0.56.1,<0.57 to >=0.59,<0.60, dropping support for versions 0.56.x through 0.58.x. Users pinned to older versions of datamodel-code-generator will need to upgrade. (Support datamodel-code-generator 0.59 #589)

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This analysis was performed by Claude Code Action

[github-actions]

🎉 Released in 0.7.0

This PR is now available in the latest release. See the release notes for details.