[BryanFRD]

Summary

• Adds 28 unit tests across all generator modules:
  • types.rs (6 tests): config filename resolution
  • rng.rs (6 tests): determinism, range, message format
  • cli.rs (8 tests): arg parsing, defaults, error cases
  • tree.rs (8 tests): blob insertion, caching, repo builder
• Adds tempfile as dev-dependency for tree tests

Closes #36

[Copilot]

Pull request overview

Adds initial Rust unit test coverage for the generator crate to validate core helper logic and reduce reliance on broken integration validation.

Changes:

• Added unit tests for config filename resolution, RNG determinism/ranges/message formatting, CLI arg parsing, and git tree/repo builder behavior.
• Introduced tempfile as a dev-dependency to support repository-in-temp-dir tests.
• Updated Cargo.lock to reflect the new dev dependency and transitive crates.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
generator/src/types.rs	Adds unit tests for resolve_config_filename defaults and overrides.
generator/src/rng.rs	Adds unit tests for RNG determinism, ranges, and generated message/time shape.
generator/src/cli.rs	Adds unit tests for flag parsing, defaults, and error cases.
generator/src/tree.rs	Adds unit tests for tree insertion, caching invalidation, and commit chaining in a temp repo.
generator/Cargo.toml	Adds tempfile under [dev-dependencies] for tests.
generator/Cargo.lock	Locks tempfile and transitive dependencies.

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[Copilot]

git2::Commit::message() can include a trailing newline depending on libgit2 behavior, so asserting exact equality to Some("initial commit") can be brittle across versions/platforms. Consider asserting on commit.summary() == Some("initial commit") or comparing commit.message().unwrap().trim_end() instead.

Suggested change

	assert_eq!(commit.message(), Some("initial commit"));
	assert_eq!(commit.summary(), Some("initial commit"));

[Copilot]

different_seeds_differ is currently probabilistic because it compares values reduced modulo 1000; two different seeds could (rarely) produce the same 10-value sequence and make the test flaky. To make this deterministic, compare next_u64() outputs directly (the test module can access the private method) or increase robustness by checking that the underlying RNG state diverges.

Suggested change

	let vals_a: Vec<usize> = (0..10).map(|_| a.usize(1000)).collect();
	let vals_b: Vec<usize> = (0..10).map(|_| b.usize(1000)).collect();
	let vals_a: Vec<u64> = (0..10).map(|_| a.next_u64()).collect();
	let vals_b: Vec<u64> = (0..10).map(|_| b.next_u64()).collect();