Fix bug with multiple var refs in quoted strings/identifiers.

- Fix incorrect result or index-out-of-range exception when multiple variable
  replacements occur in a quoted string or in a quoted identifier.

Author: sharpjs

CHANGES.md

@@ -10,6 +10,8 @@ Most lines should begin with one of these words:
 -->
 
 ## [1.0.2](https://github.com/sharpjs/Prequel/compare/release/1.0.1..release/1.0.2)
+- Fix incorrect result or index-out-of-range exception when multiple variable 
+  replacements occur in a quoted string or in a quoted identifier.
 
 ## [1.0.1](https://github.com/sharpjs/Prequel/compare/release/1.0.0..release/1.0.1)
 - Fix missing IntelliSense.

Prequel.Tests/SqlCmdPreprocessorTests.cs

@@ -224,11 +224,11 @@ public void Process_VariableReplacement_Normal(string eol, string eof)
         };
 
         var batches = preprocessor.Process(
-            Lines(eol, eof, "a $(FOO) b")
+            Lines(eol, eof, "a $(FOO) b $(foo) c")
         );
 
         batches.Should().Equal(
-            Lines(eol, eof, "a bar b")
+            Lines(eol, eof, "a bar b bar c")
         );
     }
 
@@ -285,11 +285,11 @@ public void Process_VariableReplacement_InSingleQuotedString(string eol, string
         };
 
         var batches = preprocessor.Process(
-            Lines(eol, eof, "a 'b '' $(fOO) c' d")
+            Lines(eol, eof, "a 'b '' $(fOO) $(Foo) c' d")
         );
 
         batches.Should().Equal(
-            Lines(eol, eof, "a 'b '' bar c' d")
+            Lines(eol, eof, "a 'b '' bar bar c' d")
         );
     }
 
@@ -303,11 +303,11 @@ public void Process_VariableReplacement_InBracketQuotedIdentifier(string eol, st
         };
 
         var batches = preprocessor.Process(
-            Lines(eol, eof, "a [b ]] $(fOo) c] d")
+            Lines(eol, eof, "a [b ]] $(fOo) $(foO) c] d")
         );
 
         batches.Should().Equal(
-            Lines(eol, eof, "a [b ]] bar c] d")
+            Lines(eol, eof, "a [b ]] bar bar c] d")
         );
     }
 

Prequel/SqlCmdPreprocessor.cs

@@ -350,7 +350,7 @@ private void PerformVariableReplacement(StringBuilder builder, string text)
                 return;
             }
 
-            builder.Append(text, start, match.Index);
+            builder.Append(text, start, match.Index - start);
             builder.Append(GetVariableReplacement(match));
 
             start = match.Index + match.Length;