Fix NaN regression in double parameter validation

[wnvko-msft]

Fixes #11317

Description

Reverts ArgumentOutOfRangeException.ThrowIfNegative/ThrowIfNegativeOrZero usage on double parameters introduced in PR #8408. The ThrowIfNegative helper internally uses double.IsNegative() which returns true for NaN (because NaN has the sign bit set), while the original value < 0 check returns false per IEEE 754 semantics. This caused properties like FormattedText.LineHeight to reject NaN values that were previously valid (e.g., the default TextBox.LineHeight is NaN).

Affected files:

• FormattedText.cs - ValidateFontSize, LineHeight setter, MaxTextWidth setter
• D3DImage.cs - dpiX, dpiY constructor parameters
• TextFormatterImp.cs - FontRenderingEmSize, DefaultIncrementalTab validation

Also restores removed resource strings (ParameterCannotBeNegative, ParameterMustBeBetween, ParameterMustBeGreaterThanZero) and their xlf translation entries.

Customer Impact

Applications that pass NaN to double properties (most commonly FormattedText.LineHeight = textBox.LineHeight where the default is NaN) now throw ArgumentOutOfRangeException unexpectedly. This breaks existing code that worked in .NET Framework and up to .NET 8.

Regression

Yes. This is a regression introduced in .NET 9 by PR #8408. The behavior worked correctly in .NET Framework and all versions through .NET 8.

Testing

Added unit tests in PresentationCore.Tests covering the NaN regression:

• FormattedTextTests: Verifies LineHeight and MaxTextWidth accept double.NaN and 0.0 without throwing, while negative values still throw ArgumentOutOfRangeException.
• D3DImageTests: Verifies constructor accepts double.NaN for DPI parameters without throwing, while negative values still throw ArgumentOutOfRangeException.

Risk

Low. This is a targeted revert of the specific ThrowIfNegative calls on double parameters back to the original manual comparison pattern. Integer-parameter usages of ThrowIfNegative (which have no NaN concern) are left unchanged. The fix restores the exact validation semantics from .NET 8 and earlier.

Microsoft Reviewers: Open in CodeFlow

[Copilot]

Pull request overview

This PR fixes a .NET 9 regression in WPF where double-typed parameters/properties began rejecting NaN due to ArgumentOutOfRangeException.ThrowIfNegative* using floating-point sign-bit semantics that differ from the historical value < 0 checks. It restores the pre-.NET 9 validation behavior (notably allowing NaN where it previously flowed through), reintroduces the prior localized resource strings used by WPF’s custom exceptions, and adds targeted unit tests to prevent regressions.

Changes:

• Revert double validation from ThrowIfNegative* helpers back to manual comparisons (e.g., < 0, <= 0) to preserve historical NaN behavior.
• Restore WPF resource strings (ParameterCannotBeNegative, ParameterMustBeBetween, ParameterMustBeGreaterThanZero) and corresponding XLF entries.
• Add new unit tests validating NaN acceptance and negative-value rejection for FormattedText and D3DImage.

Reviewed changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/Microsoft.DotNet.Wpf/tests/UnitTests/PresentationCore.Tests/System/Windows/Media/FormattedText.Tests.cs	Adds unit tests for FormattedText.LineHeight / MaxTextWidth NaN/zero acceptance and negative rejection.
src/Microsoft.DotNet.Wpf/tests/UnitTests/PresentationCore.Tests/System/Windows/Interop/D3DImage.Tests.cs	Adds unit tests ensuring D3DImage constructor accepts NaN DPI and rejects negative DPI.
src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Media/textformatting/TextCharacters.cs	Restores manual validation for FontRenderingEmSize to avoid NaN being treated as negative/zero by throw helpers.
src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Media/FormattedText.cs	Restores manual double validation for ValidateFontSize, LineHeight, and MaxTextWidth to preserve NaN behavior.
src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/InterOp/D3DImage.cs	Restores manual validation for DPI parameters to preserve NaN behavior.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/Strings.resx	Reintroduces removed resource strings used for validation error messages.
src/Microsoft.DotNet.Wpf/src/PresentationCore/MS/internal/TextFormatting/TextFormatterImp.cs	Restores manual range checks for FontRenderingEmSize and DefaultIncrementalTab with WPF resource-based messages.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.cs.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.de.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.es.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.fr.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.it.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.ja.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.ko.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.pl.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.pt-BR.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.ru.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.tr.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.zh-Hans.xlf	Restores XLF entries for reintroduced resource strings.
src/Microsoft.DotNet.Wpf/src/PresentationCore/Resources/xlf/Strings.zh-Hant.xlf	Restores XLF entries for reintroduced resource strings.

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