Promote Int128/UInt128 arithmetic overflow to Double by KirtiRamchandani · Pull Request #27602 · PowerShell/PowerShell
Summary
Fixes [Int128] and [UInt128] arithmetic overflow silently wrapping instead of promoting to [double] like [Int64].
Problem
[Int128]::MaxValue + [Int128]::MaxValue # wrapped instead of promoting ([Int128]::MaxValue + [Int128]::MaxValue).GetType().Name # was Int128, should be Double
Fix
- Recognize
Int128/UInt128as numeric types - Add
Int128Ops/UInt128Opswith BigInteger overflow detection - Route binary numeric operations through the custom numeric pipeline
- Add Pester tests in
ArithmeticOperators.Tests.ps1
Fixes #26677
Route Int128 and UInt128 through the numeric operations pipeline with dedicated overflow handling, matching Int64 behavior instead of relying on native wrapping operators. Fixes PowerShell#26677
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Pull request overview
Note
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Adds Int128/UInt128 support to PowerShell numeric type handling and binary operator binding, including overflow behavior (promotion to Double) and targeted tests.
Changes:
- Introduces
Int128Ops/UInt128Opsimplementations for arithmetic and comparisons. - Updates numeric type classification/helpers and type lists to include
Int128/UInt128. - Adds Pester tests validating overflow promotion to
Double(and non-overflow preservation forInt128).
Reviewed changes
Copilot reviewed 5 out of 5 changed files in this pull request and generated 9 comments.
Show a summary per file
| File | Description |
|---|---|
| test/powershell/Language/Operators/ArithmeticOperators.Tests.ps1 | Adds tests for overflow promotion behavior for 64/128-bit integer arithmetic. |
| src/System.Management.Automation/utils/ExtensionMethods.cs | Extends numeric-type helpers to treat Int128/UInt128 as numeric/integer. |
| src/System.Management.Automation/engine/runtime/Operations/NumericOps.cs | Adds operator implementations for Int128 and UInt128. |
| src/System.Management.Automation/engine/runtime/Binding/Binders.cs | Routes binary numeric ops to the new 128-bit operator implementations. |
| src/System.Management.Automation/engine/LanguagePrimitives.cs | Includes Int128/UInt128 in numeric/integer type arrays used in conversions. |
Comment on lines +2447 to +2456
| else if (target.LimitType.IsInt128Type() || arg.LimitType.IsInt128Type()) | ||
| { | ||
| opImplType = typeof(Int128Ops); | ||
| argType = typeof(Int128); | ||
| } | ||
| else if (target.LimitType.IsUInt128Type() || arg.LimitType.IsUInt128Type()) | ||
| { | ||
| opImplType = typeof(UInt128Ops); | ||
| argType = typeof(UInt128); | ||
| } |
Comment on lines +399 to +408
| internal static object Add(Int128 lhs, Int128 rhs) | ||
| { | ||
| System.Numerics.BigInteger biResult = (System.Numerics.BigInteger)lhs + (System.Numerics.BigInteger)rhs; | ||
| if (biResult >= Int128.MinValue && biResult <= Int128.MaxValue) | ||
| { | ||
| return (Int128)biResult; | ||
| } | ||
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| return (double)biResult; | ||
| } |
Comment on lines +397 to +400
| internal static class Int128Ops | ||
| { | ||
| internal static object Add(Int128 lhs, Int128 rhs) | ||
| { |
| return (double)biResult; | ||
| } | ||
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| internal static object Sub(Int128 lhs, Int128 rhs) |
| return (double)biResult; | ||
| } | ||
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| internal static object Multiply(Int128 lhs, Int128 rhs) |
| return (double)biResult; | ||
| } | ||
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| internal static object Divide(Int128 lhs, Int128 rhs) |
| return (double)lhs / (double)rhs; | ||
| } | ||
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| internal static object Remainder(Int128 lhs, Int128 rhs) |
| return lhs % rhs; | ||
| } | ||
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| internal static object CompareEq(Int128 lhs, Int128 rhs) { return (lhs == rhs) ? Boxed.True : Boxed.False; } |
| # Copyright (c) Microsoft Corporation. | ||
| # Licensed under the MIT License. | ||
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| Describe "Arithmetic overflow promotion" -Tags "CI","RequireAdminOnWindows" { |