Adds ability to escape identifiers w/ tests

Author: Josh Schwartzberg

QueryBuilder.Tests/HelperTests.cs

@@ -224,5 +224,14 @@ public void ExpandParameters()
 
             Assert.Equal("where id = ? or id in (?,?) or id in ()", expanded);
         }
+
+        [Theory]
+        [InlineData(@"ANY('\{1,2,3,4,5\}')", @"\", "{", "[", @"ANY('\{1,2,3,4,5\}')")]
+        [InlineData(@"ANY('{1,2,3,4,5}')", @"\", "{", "[", @"ANY('[1,2,3,4,5}')")]
+        public void ReplaceIdentifierUnlessEscaped(string input, string escapeCharacter, string identifier, string newIdentifier, string expected)
+        {
+            var result = input.ReplaceIdentifierUnlessEscaped(escapeCharacter, identifier, newIdentifier);
+            Assert.Equal(expected, result);
+        }
     }
 }

QueryBuilder/Compilers/Compiler.cs

@@ -15,6 +15,7 @@ public partial class Compiler
         protected virtual string ColumnAsKeyword { get; set; } = "AS ";
         protected virtual string TableAsKeyword { get; set; } = "AS ";
         protected virtual string LastId { get; set; } = "";
+        protected virtual string EscapeCharacter { get; set; } = "\\";
 
         protected Compiler()
         {
@@ -809,12 +810,11 @@ public virtual string WrapIdentifiers(string input)
             return input
 
                 // deprecated
-                .Replace("{", this.OpeningIdentifier)
-                .Replace("}", this.ClosingIdentifier)
+                .ReplaceIdentifierUnlessEscaped(this.EscapeCharacter,"{", this.OpeningIdentifier)
+                .ReplaceIdentifierUnlessEscaped(this.EscapeCharacter,"}", this.ClosingIdentifier)
 
-                .Replace("[", this.OpeningIdentifier)
-                .Replace("]", this.ClosingIdentifier);
+                .ReplaceIdentifierUnlessEscaped(this.EscapeCharacter,"[", this.OpeningIdentifier)
+                .ReplaceIdentifierUnlessEscaped(this.EscapeCharacter,"]", this.ClosingIdentifier);
         }
-
     }
 }

QueryBuilder/Helper.cs

@@ -158,5 +158,15 @@ public static IEnumerable<string> Repeat(this string str, int count)
         {
             return Enumerable.Repeat(str, count);
         }
+        
+        public static string ReplaceIdentifierUnlessEscaped(this string input, string escapeCharacter, string identifier, string newIdentifier)
+        {
+            var nonEscapedRegex = new Regex($@"(?<!\{escapeCharacter}){identifier}");
+            if (nonEscapedRegex.IsMatch(identifier))
+            {
+                return nonEscapedRegex.Replace(input, newIdentifier);
+            }
+            return input.Replace(escapeCharacter + identifier, newIdentifier);
+        }
     }
 }