Match a literal ] straight after a glob class [patch]

TextFilter.Test/TextFilterTests.cs

@@ -1064,6 +1064,40 @@
 		}
 	}
 
+	[TestMethod]
+	[DataRow("[a]]", "[a][]]")]
+	[DataRow("[]]]", "[]][]]")]
+	[DataRow("*[[][0-9]]", "*[[][0-9][]]")]
+	public void ExpandGlobClassesWritesALiteralBracketAfterAClassAsItsOwnClass(string token, string expected) =>
+		Assert.AreEqual(expected, TextFilter.ExpandGlobClasses(token));
+
+	[TestMethod]
+	[DataRow("*[[][0-9]]", "items[3]", "items[3")]
+	[DataRow("[a]]", "a]", "a")]
+	[DataRow("[ab]]", "b]", "b")]
+	[DataRow("[!a]]", "b]", "b")]
+	[DataRow("*[[][0-9a-f]]", "h[c]", "h[c")]
+	[DataRow("[a]]]", "a]]", "a]")]
+	[DataRow("*[[]DEBUG]*", "x[DEBUG]y", "xDEBUGy")]
+	public void GlobClassFollowedByALiteralBracketMatchesTheBracket(string pattern, string matching, string notMatching)
+	{
+		// DotNet.Glob read a "]" straight after a class as one more member of that class, so the pattern
+		// needed one character fewer than it was written with (#172).
+		foreach (TextFilterCaseSensitivity caseSensitivity in new[] { TextFilterCaseSensitivity.CaseSensitive, TextFilterCaseSensitivity.CaseInsensitive })
+		{
+			Assert.IsTrue(TextFilter.IsMatch(matching, pattern, TextFilterType.Glob, TextFilterMatchOptions.ByWholeString, caseSensitivity), $"{pattern} should match {matching} ({caseSensitivity})");
+			Assert.IsFalse(TextFilter.IsMatch(notMatching, pattern, TextFilterType.Glob, TextFilterMatchOptions.ByWholeString, caseSensitivity), $"{pattern} should not match {notMatching} ({caseSensitivity})");
+		}
+	}
+
+	[TestMethod]
+	public void FilterWithAClassFollowedByALiteralBracketKeepsAndExcludesTheRightItems()
+	{
+		List<string> items = ["items[3]", "items[3", "notes.txt"];
+		CollectionAssert.AreEqual(new List<string> { "items[3]" }, TextFilter.Filter(items, "*[[][0-9]]").ToList());
+		CollectionAssert.AreEqual(new List<string> { "items[3", "notes.txt" }, TextFilter.Filter(items, "-*[[][0-9]]").ToList());
+	}
+
 	[TestMethod]
 	[DataRow("-readme[a-")]
 	[DataRow("!readme[a-")]

TextFilter/TextFilter.cs

@@ -125,7 +125,7 @@
 	private static readonly TimeSpan RegexMatchTimeout = TimeSpan.FromSeconds(1);
 
 	[System.Diagnostics.CodeAnalysis.SuppressMessage("Performance", "SYSLIB1045:Convert to 'GeneratedRegexAttribute'.", Justification = "Not available in older frameworks")]
 	private static Regex RegexMatchAnything() => new(".*", RegexOptions.Compiled);
 
 	// Stands in for a pattern that has already run out of time once. The timeout bounds a single
 	// IsMatch call, so without this the same pathological pattern would pay it again for every word
@@ -300,7 +300,7 @@
 
 			return ExcludedTokenPrefixes.Contains(prefix)
 				? TextFilterTokenType.Excluded
 				: RequiredTokenPrefixes.Contains(prefix)
 				? TextFilterTokenType.Required
 				: TextFilterTokenType.Optional;
 		})
@@ -535,6 +535,15 @@
 
 			result.Append(token, index, open - index).Append(rewritten);
 			index = close + 1;
+
+			// DotNet.Glob reads a "]" straight after a class as one more member of it, so "[a]]" would
+			// match "a" and not "a]". Each such "]" is written as the one-member class "[]]", which it
+			// reads as the literal the pattern means.
+			while (index < token.Length && token[index] == ']')
+			{
+				result.Append("[]]");
+				index++;
+			}
 		}
 
 		return result.Append(token, index, token.Length - index).ToString();