Reject conditional after root object

Author: xPaw

ValveKeyValue/ValveKeyValue.Test/MultipleRootObjectsTestCase.cs

@@ -53,7 +53,6 @@ public void StrayObjectEndInTextThrows()
             Assert.That(ex.Message, Does.Contain("Found data after the root object at line 4, column 1"));
         }
 
-        // A stray '}' used to end the read loop early, silently discarding everything after it.
         [Test]
         public void SecondRootObjectAfterStrayObjectEndInTextThrows()
         {
@@ -64,6 +63,18 @@ public void SecondRootObjectAfterStrayObjectEndInTextThrows()
                 () => KVSerializer.Create(KVSerializationFormat.KeyValues1Text).Deserialize(stream));
         }
 
+        [TestCase("[$NEVERDEFINED]")]
+        [TestCase("[!$NEVERDEFINED]")]
+        public void TrailingConditionalAfterRootInTextThrows(string conditional)
+        {
+            var text = "\"a\"\n{\n\t\"k\" \"v\"\n}\n" + conditional + "\n";
+
+            using var stream = new MemoryStream(Encoding.UTF8.GetBytes(text));
+            var ex = Assert.Throws<KeyValueException>(
+                () => KVSerializer.Create(KVSerializationFormat.KeyValues1Text).Deserialize(stream));
+            Assert.That(ex.Message, Does.Contain("Found data after the root object at line 5, column 1"));
+        }
+
         [Test]
         public void SecondRootObjectInBinaryThrows()
         {

ValveKeyValue/ValveKeyValue/Deserialization/KeyValues1/KV1TextReader.cs

@@ -240,6 +240,13 @@ void HandleCondition(string text)
                 throw tokenReader.MakeSyntaxException($"Found conditional while in state {stateMachine.Current} at {tokenReader.TokenStartPosition}.");
             }
 
+            // A conditional between a root object's name and its '{' is valid and applies to that
+            // object, but after the root has closed it would otherwise discard the entire document.
+            if (stateMachine.Current == KV1TextReaderState.InObjectAfterValue && stateMachine.IsAtDocumentLevel)
+            {
+                throw tokenReader.MakeSyntaxException($"Found data after the root object at {tokenReader.TokenStartPosition}, documents with multiple root objects are not supported.");
+            }
+
             bool matches;
 
             try