From f577d12fbc6a5136b238b4d8e7e361578a66ddd6 Mon Sep 17 00:00:00 2001 From: Kate Tsuyu Date: Fri, 28 Aug 2020 11:20:42 -0400 Subject: std.math.divCeil: conform to more test cases --- lib/std/math.zig | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'lib/std/math.zig') diff --git a/lib/std/math.zig b/lib/std/math.zig index fef33ead9b..03a945163a 100644 --- a/lib/std/math.zig +++ b/lib/std/math.zig @@ -623,12 +623,16 @@ fn testDivFloor() void { pub fn divCeil(comptime T: type, numerator: T, denominator: T) !T { @setRuntimeSafety(false); - if (numerator <= 0) return divTrunc(T, numerator, denominator); - if (@typeInfo(T) == .Float) { - if (denominator == 0) return error.DivisionByZero; - return @ceil(numerator / denominator); + if (denominator == 0) return error.DivisionByZero; + if (@typeInfo(T) == .Float) return @ceil(numerator / denominator); + if (T.is_signed and numerator < 0 and denominator < 0) { + if (numerator == minInt(T) and denominator == -1) + return error.Overflow; + return @divFloor(numerator + 1, denominator) + 1; } - return (try divFloor(T, numerator - 1, denominator)) + 1; + if (numerator > 0 and denominator > 0) + return @divFloor(numerator - 1, denominator) + 1; + return @divTrunc(numerator, denominator); } test "math.divCeil" { @@ -638,11 +642,18 @@ test "math.divCeil" { fn testDivCeil() void { testing.expect((divCeil(i32, 5, 3) catch unreachable) == 2); testing.expect((divCeil(i32, -5, 3) catch unreachable) == -1); + testing.expect((divCeil(i32, 5, -3) catch unreachable) == -1); + testing.expect((divCeil(i32, -5, -3) catch unreachable) == 2); + testing.expect((divCeil(i32, 0, 5) catch unreachable) == 0); + testing.expect((divCeil(u32, 0, 5) catch unreachable) == 0); testing.expectError(error.DivisionByZero, divCeil(i8, -5, 0)); testing.expectError(error.Overflow, divCeil(i8, -128, -1)); + testing.expect((divCeil(f32, 0.0, 5.0) catch unreachable) == 0.0); testing.expect((divCeil(f32, 5.0, 3.0) catch unreachable) == 2.0); testing.expect((divCeil(f32, -5.0, 3.0) catch unreachable) == -1.0); + testing.expect((divCeil(f32, 5.0, -3.0) catch unreachable) == -1.0); + testing.expect((divCeil(f32, -5.0, -3.0) catch unreachable) == 2.0); } pub fn divExact(comptime T: type, numerator: T, denominator: T) !T { -- cgit v1.2.3