fix(linter): update no-unnecessary-template-expression docs and test case

[camc314]

Update the rule documentation to match typescript-eslint behavior.
The rule catches unnecessary template expressions (interpolations),
not simple template literals without expressions.

Update test fixture to use a valid test case that triggers the rule.

[camc314]

• chore(oxlint): remove unused snapshots #17454
• fix(linter): update no-unnecessary-template-expression docs and test case #17453 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #17453 will not alter performance

_{Comparing c/12-29-fix_linter_update_no-unnecessary-template-expression_docs_and_test_case (a38892a) with main (8e83df2)¹}

Summary

✅ 4 untouched
⏩ 41 skipped²

Footnotes

1. No successful run was found on main (abb28dc) during the generation of this report, so 8e83df2 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 41 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[graphite-app]

Merge activity

• Dec 29, 10:51 AM UTC: camc314 added this pull request to the Graphite merge queue.
• Dec 29, 10:59 AM UTC: Merged by the Graphite merge queue.

[Copilot]

Pull request overview

This PR updates the no-unnecessary-template-expression linter rule documentation and test fixtures to accurately reflect that the rule targets unnecessary template expressions (interpolations), not simple template literals without expressions. The key clarification is that `hello` (template literal without interpolation) is allowed, while `${text}` (unnecessary wrapping of a string variable) should be flagged.

• Updated rule documentation with clearer explanations and more accurate examples
• Added explicit note that template literals without substitution expressions are allowed
• Updated test fixture from a non-triggering case to a valid case that properly demonstrates the rule

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
crates/oxc_linter/src/rules/typescript/no_unnecessary_template_expression.rs	Rewrote the rule documentation with accurate description, better examples, and clarification about what the rule does and doesn't flag
apps/oxlint/fixtures/tsgolint/no-unnecessary-template-expression.ts	Changed test case from `Hello world` (which doesn't trigger the rule) to `${text}` (which correctly triggers the rule)
apps/oxlint/src/snapshots/fixtures__tsgolint_--type-aware@oxlint.snap	Updated snapshot to reflect the new test case triggering the rule, increasing error count from 50 to 51

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[Copilot]

The "correct" example on line 48 shows const greeting = Hello ${name}!; which is described as "Template with non-trivial interpolation". However, this example could be misleading because according to the rule's purpose, wrapping a simple string variable in a template literal is unnecessary. The reason this is considered "correct" is because it has additional static content ("Hello " and "!") around the variable, making the template literal necessary for string composition. Consider clarifying the comment to say "Template with interpolation and static content" to better distinguish it from the incorrect example of just wrapping a variable.

Suggested change

	/// // Template with non-trivial interpolation
	/// // Template with interpolation and static content

[Copilot]

Unused variable wrapped.

Suggested change

const wrapped = `${text}`;