test: add tests for gadget utility module

[mrhapile]

Add tests for gadget utility module

ref #20

This PR adds a test file for the utility functions implemented in src/gadgets/utility.tsx.

The tests verify that the exported utility functions behave correctly for valid inputs and handle edge cases safely. These tests follow the existing testing conventions used in the repository and contribute to improving the overall test coverage of the gadgets module.

How to use

Reviewers can validate this PR by running the test suite locally.

Steps:

1. Checkout this branch.
2. Install dependencies if necessary.
3. Run the test suite.

Testing done

Commands executed:

npm install
npm test

Result:

The test suite runs successfully and the new test file src/gadgets/utility.test.tsx executes without errors.

[Copilot]

Pull request overview

Adds Vitest coverage for the gadgets utility helpers in src/gadgets/utility.tsx to improve test coverage for the gadgets module (ref #20).

Changes:

• Added a new utility.test.tsx file covering processDataColumn, processGadgetData, createGadgetCallbacks, and MAX_DATA_LIMIT.
• Included a mock for Headlamp Link to validate React element creation without relying on the actual plugin components.

---

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[Copilot]

This file’s indentation/formatting (e.g., 4-space indents) doesn’t match the prevailing formatting in this repo (most TS/TSX files use 2-space indentation and appear Prettier-formatted, e.g. src/gadgets/utility.tsx). Running the repo formatter on this test file will avoid noisy diffs and potential lint failures.

[Copilot]

The mock fns (mockSetGadgetData/mockSetBufferedGadgetData/mockSetLoading) are shared across multiple top-level describe blocks, but vi.clearAllMocks() is only run in the first describe('gadget utility module', ...). This can cause test-order coupling as the file grows (later tests may inherit call history). Consider adding a top-level beforeEach (or afterEach) to reset mocks for the whole file, or move all tests under the same describe that has the reset.

Suggested change

	describe('gadget utility module', () => {
	beforeEach(() => {
	vi.clearAllMocks();
	});
	beforeEach(() => {
	vi.clearAllMocks();
	});
	describe('gadget utility module', () => {

[Copilot]

This test is asserting a thrown TypeError for a missing field, which contradicts the PR description that utility functions “handle edge cases safely” and will lock in a crashy behavior (and brittle error text). Prefer updating processDataColumn to return a safe value (e.g., ''/null) when getProperty returns undefined, and assert that behavior here; alternatively, if throwing is intended, update the test name/description to match and avoid asserting on an engine-specific error message.

[Copilot]

The test name says it verifies slicing to MAX_DATA_LIMIT, but it only adds a single element and never exercises the slicing logic. Either extend the test to append > MAX_DATA_LIMIT items and assert the result length/contents, or rename the test to reflect what it actually checks (that non-metric data is massaged and appended).

Suggested change

	const prevState = { ds1: [] }; // ds1 mapping
	const nextState = updaterFn(prevState);
	expect(Array.isArray(nextState.ds1)).toBe(true);
	expect(nextState.ds1.length).toBe(1);
	expect(nextState.ds1[0]).toEqual({ 'k8s.podName': 'my-pod' });
	const existingItems = Array.from({ length: MAX_DATA_LIMIT }, (_v, i) => ({
	'k8s.podName': `existing-${i}`,
	}));
	const prevState = { ds1: existingItems }; // ds1 mapping
	const nextState = updaterFn(prevState);
	expect(Array.isArray(nextState.ds1)).toBe(true);
	expect(nextState.ds1.length).toBe(MAX_DATA_LIMIT);
	// Oldest item should have been dropped, newest massaged item appended
	expect(nextState.ds1[0]).toEqual({ 'k8s.podName': 'existing-1' });
	expect(nextState.ds1[nextState.ds1.length - 1]).toEqual({ 'k8s.podName': 'my-pod' });

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 2 comments.

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[Copilot]

The test file indentation/formatting doesn’t match the repository’s typical Prettier style (most TS/TSX files use 2-space indentation). Please run the formatter (or reformat this block) so CI lint/format checks don’t fail due to inconsistent whitespace.

Suggested change

	Link: ({ routeName, params, children }: any) => (
	<a data-testid="mock-link" href={`${routeName}/${JSON.stringify(params)}`}>
	{children}
	</a>
	),
	Link: ({ routeName, params, children }: any) => (
	<a data-testid="mock-link" href={`${routeName}/${JSON.stringify(params)}`}>
	{children}
	</a>
	),

[Copilot]

React is imported but never referenced. If the project is using the automatic JSX runtime (as several files do), this will be flagged as an unused import; consider removing it to avoid lint/tsc failures.

Suggested change

import React from 'react';

[illume]

Thanks for your contributions!

Please let us know if you want to continue this by addressing the review comments? If not that's ok, we can take over the PR (and finish it or close it ourselves).