From e89a35d5e03c8139596743b9f88ddfc18a484808 Mon Sep 17 00:00:00 2001
From: Rob Martens <robert.martens@gmail.com>
Date: Wed, 1 May 2024 14:27:30 -0400
Subject: [PATCH] Allow negative literals in conditions

---
 MonoDevelop.MSBuild.Tests/MSBuildConditionTests.cs              | 2 ++
 .../Language/Expressions/ExpressionParser.Conditions.cs         | 2 +-
 MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.cs    | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/MonoDevelop.MSBuild.Tests/MSBuildConditionTests.cs b/MonoDevelop.MSBuild.Tests/MSBuildConditionTests.cs
index 65cd3407..a939e574 100644
--- a/MonoDevelop.MSBuild.Tests/MSBuildConditionTests.cs
+++ b/MonoDevelop.MSBuild.Tests/MSBuildConditionTests.cs
@@ -131,6 +131,8 @@ public void TestParenGrouping ()
 		[TestCase ("'$(foo)' == '' and ('$(bar)' == '')")] // paren group at end of expression string
 		[TestCase ("")] // empty expression
 		[TestCase (" ")] // whitespace only
+		[TestCase ("'$(foo)' > 1.0")] // decimal literal
+		[TestCase ("'$(foo)' > -1.0")] // negative decimal literal
 		public void TestParseNoError (string expressionString)
 		{
 			var expression = ExpressionParser.ParseCondition (expressionString, 0);
diff --git a/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.Conditions.cs b/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.Conditions.cs
index 8617dac3..1d80af84 100644
--- a/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.Conditions.cs
+++ b/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.Conditions.cs
@@ -161,7 +161,7 @@ static ExpressionNode ParseConditionOperand (string buffer, ref int offset, int
 			int start = offset;
 
 			var ch = buffer[start];
-			if (ch == '.' || char.IsDigit (ch)) {
+			if (ch == '-' || ch == '.' || char.IsDigit (ch)) {
 				return ReadArgumentNumber (buffer, ref offset, endOffset, baseOffset, out hasError);
 			}
 
diff --git a/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.cs b/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.cs
index 22c4d828..34cd60f2 100644
--- a/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.cs
+++ b/MonoDevelop.MSBuild/Language/Expressions/ExpressionParser.cs
@@ -642,7 +642,7 @@ static ExpressionNode ReadArgumentNumber (string buffer, ref int offset, int end
 					goto case '0';
 				case ',': case ')': case ']': case ' ': case '\r': case '\n':  case '\t':
 					return Result (ref offset, out hasError);
-				case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9':
+				case '-': case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9':
 					offset++;
 					continue;
 				default: