test: unit tests for get_package and get_partitions methods

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Addresses review feedback from #54 requesting unit test coverage for the new get_package and get_partitions methods in project models.

Changes

• Added tests for Project.get_package():

  • Successful package retrieval
  • Error when no packages defined
  • Error when package not found

• Added tests for PackagesProject.get_partitions():

  • Returns ["default"] when no packages defined
  • Returns ["default", "package/<name>", ...] when packages defined

def test_get_package_success(default_project):
    package = default_project.get_package("package-1")
    assert package.version == "2.0"

def test_get_partitions_with_packages():
    packages_project = project.PackagesProject(
        packages={"pkg-a": Package(version="1.0"), "pkg-b": Package(version="2.0")}
    )
    result = packages_project.get_partitions()
    assert result == ["default", "package/pkg-a", "package/pkg-b"]

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[cmatsuoka]

We can land this directly on main after landing #54

[Copilot]

Pull request overview

This PR adds unit test coverage for two methods in project models: Project.get_package() and PackagesProject.get_partitions(), addressing review feedback from a previous PR (#54).

• Tests for successful package retrieval and error cases (no packages, package not found)
• Tests for partition generation with and without packages defined

---

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[Copilot]

The test uses multiple assertions to verify the result instead of a single comprehensive assertion. Since get_partitions() returns a deterministic list, use a single assertion comparing the full result. Replace lines 131-135 with: assert result == [\"default\", \"package/pkg-a\", \"package/pkg-b\"]. This is clearer, more maintainable, and catches ordering issues.

Suggested change

	assert result is not None
	assert "default" in result
	assert "package/pkg-a" in result
	assert "package/pkg-b" in result
	assert len(result) == 3
	assert result == ["default", "package/pkg-a", "package/pkg-b"]

[Copilot]

This assertion is redundant. The get_partitions() method always returns a list (either [\"default\"] or a list with packages), never None. The return type annotation list[str] | None appears to allow None, but examining the implementation shows it always returns a list. This check can be removed.

Suggested change

assert result is not None

[Copilot]

This assertion is redundant. The get_package() method either returns a Package or raises an exception, so it can never return None. Line 91 already verifies the package content by checking the version. Remove this assertion.

Suggested change

assert package is not None

[lengau]

@copilot rebase this on main.

[Copilot]

@copilot rebase this on main.

I'm unable to perform git rebase operations as I don't have access to force push. Could you please rebase this branch on main?