Strengthen test assertions across the suite#883
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… unseeded random Resolves all errors and warnings from the test-quality auditor across 19 existing test files. No new tests added, no production code changed. - Replace exact == on floating-point values with abs(a - b) < 1e-6 - Replace try! with try? in test HTML helpers - Replace weak assertions (#expect != nil) with #require() for fail-fast - Replace unseeded random with deterministic test data
Replace fixed test values with a SplitMix64-based seeded generator so tests remain deterministic while exercising realistic random inputs.
MrSkwiggs
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MrSkwiggs
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Thanks for the contributions 👍 A lot of these are quite nice, though some I believe are not entirely warranted. I've left comments below, please have a look 🙏
| var isPrimitive: Bool = Bool.random() | ||
| var isPrimitive: Bool | ||
| var body: some HTML { self } | ||
| func render() -> String { "<div id=\"\(id)\"></div>" } | ||
| } | ||
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| let mockHTMLElements = [ | ||
| MockHTML(id: "a"), | ||
| MockHTML(id: "b"), | ||
| MockHTML(id: "c") | ||
| ] | ||
| let mockHTMLElements: [MockHTML] = { | ||
| var rng = SeededRandomNumberGenerator(seed: 99) | ||
| return [ | ||
| MockHTML(id: "a", isPrimitive: rng.nextBool()), | ||
| MockHTML(id: "b", isPrimitive: rng.nextBool()), | ||
| MockHTML(id: "c", isPrimitive: rng.nextBool()) | ||
| ] | ||
| }() |
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I'm not entirely convinced adding seeded RNG here is really necessary
| func defaultDuration() async throws { | ||
| let data = AnimatableData(.opacity, value: "0") | ||
| #expect(data.duration == 0.35) | ||
| #expect(abs(data.duration - 0.35) < 1e-6) |
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I'd much prefer if we wrote an overload or helper function that did this for us in a more controlled manner. Right now this is very repetitive and easy to forget adding in future tests.
| #expect(text != nil) | ||
| _ = try #require(element.as(Text.self)) |
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In this exact scenario where we don't actually need the non-optional value, #require does not offer any benefit over checking for optionality with #expect(text != nil). In fact I would argue these specific changes make the test cases ever so slightly less readable
| let hoverID = try #require(firstHoverAnimationID(in: output)) | ||
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| #expect(hoverID != nil) | ||
| _ = hoverID |
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I don't believe this is a good change; we're now silently dismissing a test expectation
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| /// A deterministic random number generator using SplitMix64. | ||
| /// Use in tests to get reproducible "random" values across runs. | ||
| struct SeededRandomNumberGenerator: RandomNumberGenerator { |
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Again, not convinced we need this
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Summary
Small housekeeping pass over the existing test suite to tighten up assertions:
==on floating-point values with tolerance-based checks (abs(a - b) < 1e-6) in AnimatableData, Animation, Transition, and Percentage teststry!withtry?in the shared HTML test helpers (String-TestingHTML.swift), so a bad regex pattern returns nil instead of crashing the test runner#expect(x != nil)tolet x = try #require(x)where the unwrapped value is used by later assertions — gives a clear failure message and stops the test early instead of cascading nil-related failuresInt.random(),Double.random(), andBool.random()with fixed values so tests are reproducible across runsNo new tests, no production code changes. All 1,177 existing tests continue to pass.
Test plan
swift testpasses (1,177 tests, 214 suites)Sources/