Clarify AlwaysUseLowerCamelCase docs on the test-code carve-out

[adityasingh2400]

Problem

The AlwaysUseLowerCamelCase rule documentation says the rule "does not apply to test code" (code that imports XCTest or has a function marked with @Test). That is not what the rule does. The test-code carve-out only relaxes the restriction on underscores; the lower camel-case requirement still applies, so a test function whose name begins with a capital letter is still diagnosed.

For example, this still produces a warning even though the function is marked @Test:

import Testing

struct MyTests {
  @Test func MyTestCase() {}  // warning: [AlwaysUseLowerCamelCase] rename the function 'MyTestCase' using lowerCamelCase
}

This matches the behavior described by the maintainer in #1129: underscores are permitted in test names by convention, but UpperCamelCase is not allowed just because something is a test.

Fix

Reword the rule's doc comment to describe the actual behavior: underscores are allowed in test function names, while the lower camel-case requirement otherwise still applies. RuleDocumentation.md is regenerated from that comment via swift run generate-swift-format.

This is a documentation-only change; the rule's behavior is unchanged.

Testing

swift build and swift test --filter AlwaysUseLowerCamelCaseTests pass. The existing tests already cover both halves of the clarified wording: underscores are accepted in test names (testIgnoresUnderscoresInTestNames, testIgnoresFunctionsWithTestAttributes) while invalid casing is still flagged (testInvalidFunctionCasing).

Fixes #1129.

[allevato]

Suggested change

	/// code is defined as code which:
	/// * Contains the line `import XCTest`
	/// * The function is marked with `@Test` attribute
	/// * Has a function marked with the `@Test` attribute
	/// functions are functions that either:
	/// * start with `test` in a file containing `import XCTest`, or
	/// * are marked with the `@Test` attribute.

[adityasingh2400]

Thanks @allevato, applied your suggested wording verbatim. The doc comment now reads "Test functions are functions that either: start with test in a file containing import XCTest, or are marked with the @Test attribute." Build and strict lint both pass.

[allevato]

Thanks @allevato, applied your suggested wording verbatim. The doc comment now reads "Test functions are functions that either: start with test in a file containing import XCTest, or are marked with the @Test attribute." Build and strict lint both pass.

Please make sure the Markdown file is updated as well (running the generator will do this).

[adityasingh2400]

Done, regenerated Documentation/RuleDocumentation.md with generate-swift-format. The AlwaysUseLowerCamelCase section now matches the updated doc comment. Ready for another look.

[adityasingh2400]

Heads up: the red CI here is a transient infrastructure failure, not the doc change. Every failed job, including unrelated ones like the shell, YAML, and license-header checks, failed at the Checkout repository step and then skipped the actual check. The only change in the last commit is the regenerated RuleDocumentation.md, so a re-run should bring it back green. I do not have permission to re-run it from my side.