[Windows] Fix for Argument Exception raised when the GetStringSize method of ICanvas called with default font

[SyedAbdulAzeemSF4852]

Issue Details

• Argument Exception raised when the GetStringSize method of ICanvas called with default font.

Root Cause

• The Weight property of the FontWeight class, used when creating a CanvasTextFormat object, only accepts values in the range of 1 to 999. However, when the GetStringSize method is called using the default font, its weight is 0. Assigning this value causes an ArgumentException because it falls outside the expected range.

Description of Change

• Before assigning the font's weight to the Weight property of the FontWeight class while creating a CanvasTextFormat object, clamped the font's Weight value using Math.Clamp to ensure it stays within the valid range of 1 to 999.

• Reference : FontWeight Struct

Validated the behaviour in the following platforms

• Windows
• Android
• iOS
• Mac

Issues Fixed

Fixes #20419

Output

Before Fix	After Fix

[Copilot]

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (3)

src/Graphics/src/Graphics/Platforms/Windows/PlatformStringSizeService.cs:33

• Consider adding a unit test that explicitly verifies the clamped FontWeight value to prevent potential regressions.

FontWeight = new FontWeight { Weight = (ushort)Math.Clamp(font.Weight, 1, 999) },

src/Graphics/src/Graphics/Platforms/Windows/FontExtensions.cs:33

• Consider adding a unit test to verify that FontWeight is correctly clamped for both non-null and null font scenarios.

FontWeight = new FontWeight { Weight = (ushort)Math.Clamp(font?.Weight ?? FontWeights.Regular, 1, 999) },

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue20419.cs:15

• [nitpick] Consider enhancing the test to include assertions that verify the clamped font weight instead of solely waiting for a UI element, ensuring that the fix is directly validated.

[Test]

[jsuarezruiz]

/azp run MAUI-UITests-public

[jsuarezruiz]

We need the same approach in different classes. Can create an extension method and reuse it.

[rmarinho]

should we add a extension method to parse this?

[SyedAbdulAzeemSF4852]

@jsuarezruiz , I've updated the fix by creating the CanvasTextFormat instance using the ToCanvasTextFormat extension method defined in FontExtensions.

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[jsuarezruiz]

/azp run MAUI-UITests-public

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Azure Pipelines successfully started running 1 pipeline(s).

The base branch was changed.