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Math.max starts from -Infinity and Math.min from +Infinity - #31
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Math.max started from Number.MIN_VALUE, the smallest positive number, so the maximum of negative numbers was 2.2e-308 (Math.max(-3, -5)). Math.min started from Number.MAX_VALUE, so Math.min() and Math.min(Infinity) were 1.79e308. Both now start from the infinities, as in JavaScript, and a NaN argument makes the result NaN. tests/math.ts already checks Math.max(-1, -7), but through an `any` helper whose `!==` could not see the difference (compiler PR #535). The new tests/math_max_min.ts checks with typed comparisons. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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Problem
Math.maxstarted its running maximum atNumber.MIN_VALUE, which is the smallest positive double, not the most negative one. So any all-negative input returned 2.2e-308:Math.minstarted atNumber.MAX_VALUE, soMath.min()andMath.min(Infinity)returned 1.79e308 instead ofInfinity.Reported in TypeScriptCompiler
docs/bugs/native-ts-graphics-findings.md(issue 5, a camera pitch clamp broke).Fix
Start from
-Infinity/+Infinity, and returnNaNif any argument isNaN, as JavaScript does.Why tests/math.ts didn't catch it
tests/math.ts:107checksisEq(Math.max(-1, -7), -1). ButisEq(x: any, y: any)uses!==, and the compiler answered false for ananynumber compared with ananyinteger. Compiler PR ASDAlexander77/TypeScriptCompiler#535 fixes that; with it,tests/math.tsreports this bug. The newtests/math_max_min.tsuses typed comparisons, so it fails on the old library with either compiler.Testing
tests.ps1release compile + JIT (gc), with a compiler built from current main plus #535: 163/163 pass on both. The new test fails against the current library (assertion failed: Math.max(-3, -5)).🤖 Generated with Claude Code