Normalization APIs using the spans

[tarekgh]

Fixes #87757

[ghost]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[ghost]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[Copilot]

Copilot reviewed 5 out of 7 changed files in this pull request and generated 1 suggestion.

Files not reviewed (2)

• src/libraries/System.Runtime/ref/System.Runtime.cs: Evaluated as low risk
• src/libraries/System.Private.CoreLib/src/System/Globalization/Normalization.Nls.cs: Evaluated as low risk

Comments skipped due to low confidence (4)

src/libraries/System.Private.CoreLib/src/System/Globalization/Normalization.Icu.cs:229

• The parameter name 'strInput' should be 'source' to match the other methods.

private static void ValidateArguments(ReadOnlySpan<char> strInput, NormalizationForm normalizationForm, string paramName = "strInput")

src/libraries/System.Runtime/tests/System.Globalization.Extensions.Tests/Normalization/StringNormalizationTests.cs:74

• [nitpick] The comment about the extra character in the buffer for NLS should be documented more clearly.

Span<char> destination = new char[expected.Length + 1]; // NLS sometimes need extra character in the buffer mostly if need to insert the null terminator

src/libraries/System.Runtime/tests/System.Globalization.Extensions.Tests/Normalization/StringNormalizationTests.cs:121

• Ensure consistent error messages for invalid normalization forms.

Assert.Throws<ArgumentException>(() => "\uFB01".Normalize((NormalizationForm)7));

src/libraries/System.Private.CoreLib/src/System/StringNormalizationExtensions.cs:82

• The summary comment for the method GetNormalizedLength is not properly aligned. Ensure that all summary comments are consistent in formatting and detail.

/// <summary>

[ericstj]

/ba-g #110517 fixed build issue here

[ericstj]

Feedback has been addressed, builds passing modulo one known issue. I noticed a small whitespace issue which I will fix and merge.