Escape special characters in regular expressions generated for LINQ queries involving strings.

Author: rstam

Driver/Linq/Translators/SelectQuery.cs

@@ -824,7 +824,7 @@ private IMongoQuery BuildStringQuery(MethodCallExpression methodCallExpression)
                 return null;
             }
 
-            var pattern = (string)constantExpression.Value; // TODO: escape value
+            var pattern = Regex.Escape((string)constantExpression.Value);
             switch (methodCallExpression.Method.Name)
             {
                 case "Contains": pattern = ".*" + pattern + ".*"; break;
@@ -1103,8 +1103,7 @@ private string GetTrimCharsPattern(Expression trimCharsExpression)
                 }
                 else
                 {
-                    // TODO: handle special characters better
-                    sb.Append(c.ToString());
+                    sb.Append(Regex.Escape(c.ToString()));
                 }
             }
             if (sawDash)

DriverUnitTests/Linq/SelectQueryTests.cs

@@ -4259,6 +4259,29 @@ public void TestWhereSContainsAbcNot()
             Assert.AreEqual(4, Consume(query));
         }
 
+        [Test]
+        public void TestWhereSContainsDot()
+        {
+            var query = from c in _collection.AsQueryable<C>()
+                        where c.S.Contains(".")
+                        select c;
+
+            var translatedQuery = MongoQueryTranslator.Translate(query);
+            Assert.IsInstanceOf<SelectQuery>(translatedQuery);
+            Assert.AreSame(_collection, translatedQuery.Collection);
+            Assert.AreSame(typeof(C), translatedQuery.DocumentType);
+
+            var selectQuery = (SelectQuery)translatedQuery;
+            Assert.AreEqual("(C c) => c.S.Contains(\".\")", ExpressionFormatter.ToString(selectQuery.Where));
+            Assert.IsNull(selectQuery.OrderBy);
+            Assert.IsNull(selectQuery.Projection);
+            Assert.IsNull(selectQuery.Skip);
+            Assert.IsNull(selectQuery.Take);
+
+            Assert.AreEqual("{ \"s\" : /\\./s }", selectQuery.BuildQuery().ToJson());
+            Assert.AreEqual(0, Consume(query));
+        }
+
         [Test]
         public void TestWhereSEndsWithAbc()
         {
@@ -4794,7 +4817,7 @@ public void TestWhereSTrimStartsWithXyzNot()
         public void TestWhereSTrimStartTrimEndToLowerContainsXyz()
         {
             var query = from c in _collection.AsQueryable<C>()
-                        where c.S.TrimStart(' ', '-', '\t').TrimEnd().ToLower().Contains("xyz")
+                        where c.S.TrimStart(' ', '.', '-', '\t').TrimEnd().ToLower().Contains("xyz")
                         select c;
 
             var translatedQuery = MongoQueryTranslator.Translate(query);
@@ -4803,13 +4826,13 @@ where c.S.TrimStart(' ', '-', '\t').TrimEnd().ToLower().Contains("xyz")
             Assert.AreSame(typeof(C), translatedQuery.DocumentType);
 
             var selectQuery = (SelectQuery)translatedQuery;
-            Assert.AreEqual("(C c) => c.S.TrimStart(Char[]:{ ' ', '-', '\t' }).TrimEnd(Char[]:{ }).ToLower().Contains(\"xyz\")", ExpressionFormatter.ToString(selectQuery.Where));
+            Assert.AreEqual("(C c) => c.S.TrimStart(Char[]:{ ' ', '.', '-', '\t' }).TrimEnd(Char[]:{ }).ToLower().Contains(\"xyz\")", ExpressionFormatter.ToString(selectQuery.Where));
             Assert.IsNull(selectQuery.OrderBy);
             Assert.IsNull(selectQuery.Projection);
             Assert.IsNull(selectQuery.Skip);
             Assert.IsNull(selectQuery.Take);
 
-            Assert.AreEqual("{ \"s\" : /^[ \t-]*.*xyz.*\\s*$/is }", selectQuery.BuildQuery().ToJson());
+            Assert.AreEqual("{ \"s\" : /^[\\ \\.\\t-]*.*xyz.*\\s*$/is }", selectQuery.BuildQuery().ToJson());
             Assert.AreEqual(1, Consume(query));
         }