Fix TrimmedEquals logic and add negative test cases

Correct TrimmedEquals null/empty handling for StringSegment overloads. Update tests to use correct overloads and add negative cases for both char and span trimming.

Author: electricessence

Source/Extensions.Equals.cs

@@ -146,9 +146,8 @@ public static bool TrimmedEquals(this string? source, ReadOnlySpan<char> other,
 	/// <inheritdoc cref="TrimmedEquals(string?, StringSegment, ReadOnlySpan{char}, StringComparison)"/>
 	public static bool TrimmedEquals(this string? source, StringSegment other, char trimChar, StringComparison comparisonType = StringComparison.Ordinal)
 	{
-		bool otherHasValue = !other.HasValue;
-		if (source is null) return otherHasValue;
-		if (otherHasValue) return false;
+		if (source is null) return !other.HasValue;
+		if (!other.HasValue) return false;
 		int slen = source.Length, olen = other.Length;
 		if (slen < olen) return false;
 		ReadOnlySpan<char> span = source.AsSpan().Trim(trimChar);

Tests/EqualityTests.cs

@@ -102,7 +102,7 @@ public void TrimmedEquals(string value, string? other, StringComparison comparis
 	public void TrimmedEqualsChar(string value, string? other, StringComparison comparison = StringComparison.Ordinal)
 	{
 		Assert.True(value.TrimmedEquals(other, ' ', comparison));
-		Assert.True(value.TrimmedEquals(other!.AsSegment(), comparison));
+		Assert.True(value.TrimmedEquals(other!.AsSegment(), ' ', comparison));
 		Assert.True(value.TrimmedEquals(other.AsSpan(), ' ', comparison));
 	}
 
@@ -115,6 +115,28 @@ public void TrimmedEqualsChar(string value, string? other, StringComparison comp
 	public void TrimmedEqualsChars(string? value, string? other, StringComparison comparison = StringComparison.Ordinal)
 	{
 		Assert.True(value.TrimmedEquals(other, Chars.Span, comparison));
+		Assert.True(value.TrimmedEquals(other!.AsSegment(), Chars.Span, comparison));
 		Assert.True(value.TrimmedEquals(other.AsSpan(), Chars.Span, comparison));
 	}
+
+	[Fact]
+	public void TrimmedEqualsCharNegativeCases()
+	{
+		Assert.False(" hello ".TrimmedEquals("world", ' '));
+		Assert.False(" hello ".TrimmedEquals("world".AsSegment(), ' '));
+		Assert.False(" hello ".TrimmedEquals("hell", ' '));
+		Assert.False(" hello ".TrimmedEquals("hell".AsSegment(), ' '));
+		Assert.False("x".TrimmedEquals("y".AsSegment(), ' '));
+		Assert.False("  x  ".TrimmedEquals("y".AsSegment(), ' '));
+	}
+
+	[Fact]
+	public void TrimmedEqualsCharsNegativeCases()
+	{
+		Assert.False("	 hello ".TrimmedEquals("world", Chars.Span));
+		Assert.False("	 hello ".TrimmedEquals("world".AsSegment(), Chars.Span));
+		Assert.False("	 hello ".TrimmedEquals("hell", Chars.Span));
+		Assert.False("	 hello ".TrimmedEquals("hell".AsSegment(), Chars.Span));
+		Assert.False("	x	".TrimmedEquals("y".AsSegment(), Chars.Span));
+	}
 }