Rust: use all features by default

[redsun82]

This makes rust analysis turn on all features by default. A more restricted set of features can be specified via the cargo_features extractor option. In particular setting it to default will use default features instead (no features if no default is set for a crate).

Notice that this implementation currently does not allow to turn off all features for crates that have a non-empty default. It's to be discussed if we want to allow that, but we could use a special value like - or ! for that.

[Copilot]

Pull Request Overview

Enables all Cargo features by default in the extractor and lets users restrict features via the cargo_features option, with tests and docs updated accordingly.

• Introduces a cargo_features() helper to centralize default/all/selected feature logic and uses it in to_cargo_config.
• Expands integration tests to cover combinations of default, explicit features, and crates with non-empty default lists.
• Updates extractor option documentation to reflect that all features are enabled by default and default must be explicitly specified to limit to default features.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
rust/ql/integration-tests/options/features/test_features_option.py	Adds new test cases and marks to cover default-feature scenarios and crates with defaults
rust/extractor/src/config.rs	Adds cargo_features() helper and replaces inline logic in to_cargo_config
rust/codeql-extractor.yml	Updates cargo_features option description to match new default behavior

Comments suppressed due to low confidence (1)

rust/extractor/src/config.rs:129

• [nitpick] Method name cargo_features shadows the cargo_features field and could be confusing; consider renaming it to compute_cargo_features.

fn cargo_features(&self) -> CargoFeatures {

[Copilot]

Add a doc comment for cargo_features() to explain its behavior, particularly how default features and the deprecated '*' wildcard are handled.

Suggested change

	/// Determines the Cargo features to be used based on the configuration.
	///
	/// - If the `cargo_features` list is empty or contains the deprecated `'*'` wildcard,
	/// all features are enabled (`CargoFeatures::All`).
	/// - Otherwise, a subset of features is selected (`CargoFeatures::Selected`):
	/// - The `features` list excludes the `default` feature.
	/// - The `no_default_features` flag is set to `true` if the `default` feature is not present
	/// in the `cargo_features` list.
	///
	/// # Note
	/// The `'*'` wildcard is deprecated but retained for backward compatibility.

[aibaars]

Looks good to me. One typo that needs fixing, but otherwise OK.