Fix #148 allow text reader skip over container

amazon-ion · Dec 19, 2022 · 627d26f · 627d26f
1 parent ff73b85
commit 627d26f
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Showing 2 changed files with 41 additions and 3 deletions.
diff --git a/Amazon.IonDotnet.Tests/Internals/TextReaderTest.cs b/Amazon.IonDotnet.Tests/Internals/TextReaderTest.cs
@@ -350,5 +350,32 @@ public void Blob_PartialRead(int size, int step)
             var reader = new UserTextReader(text);
             ReaderTestCommon.Blob_PartialRead(size, step, reader);
         }
+
+        [TestMethod()]
+        public void SkipOverListInStruct()
+        {
+            var reader = new UserTextReader("{ somelist: [ 1 ] }");
+            Assert.AreEqual(IonType.Struct, reader.MoveNext());
+            reader.StepIn();
+            Assert.AreEqual(IonType.List, reader.MoveNext());
+            Assert.AreEqual("somelist", reader.CurrentFieldName);
+            // Now skip over the list instead of stepping into it
+            Assert.AreEqual(IonType.None, reader.MoveNext());
+            reader.StepOut(); // Step out of struct
+            Assert.AreEqual(IonType.None, reader.MoveNext());
+        }
+
+        [TestMethod()]
+        public void SkipOverStructInList()
+        {
+            var reader = new UserTextReader("[{}]");
+            Assert.AreEqual(IonType.List, reader.MoveNext());
+            reader.StepIn();
+            Assert.AreEqual(IonType.Struct, reader.MoveNext());
+            // Skip over the struct instead of stepping in
+            Assert.AreEqual(IonType.None, reader.MoveNext());
+            reader.StepOut(); // Step out of list
+            Assert.AreEqual(IonType.None, reader.MoveNext());
+        }
     }
 }
diff --git a/Amazon.IonDotnet/Internals/Text/RawTextReader.cs b/Amazon.IonDotnet/Internals/Text/RawTextReader.cs
@@ -152,6 +152,8 @@ public void StepIn()
 
             this.state = GetStateAtContainerStart(this.valueType);
             this.containerStack.PushContainer(this.valueType);
+            var closeSymbol = this.GetClosingTokenForContainerType(this.valueType);
+            this.expectedContainerClosingSymbol.Push(closeSymbol);
             this.scanner.MarkTokenFinished();
 
             this.FinishValue();
@@ -605,17 +607,14 @@ private void ParseNext()
                         break;
                     case ActionStartStruct:
                         this.valueType = IonType.Struct;
-                        this.expectedContainerClosingSymbol.Push(TextConstants.TokenCloseBrace);
                         this.state = StateBeforeFieldName;
                         return;
                     case ActionStartList:
                         this.valueType = IonType.List;
-                        this.expectedContainerClosingSymbol.Push(TextConstants.TokenCloseSquare);
                         this.state = StateBeforeAnnotationContained;
                         return;
                     case ActionStartSexp:
                         this.valueType = IonType.Sexp;
-                        this.expectedContainerClosingSymbol.Push(TextConstants.TokenCloseParen);
                         this.state = StateBeforeAnnotationSexp;
                         return;
                     case ActionStartLob:
@@ -757,6 +756,18 @@ private char GetCharacterValueOfClosingContainerToken(int tokenCode)
             }
         }
 
+        private int GetClosingTokenForContainerType(IonType containerType)
+        {
+            switch (containerType)
+            {
+                case IonType.Struct: return TextConstants.TokenCloseBrace;
+                case IonType.List: return TextConstants.TokenCloseSquare;
+                case IonType.Sexp: return TextConstants.TokenCloseParen;
+                default:
+                    throw new Exception("Invalid value type while determining expectedContainerClosingSymbol");
+            }
+        }
+
         private void ReadNullType(bool trailingWhitespace)
         {
             var kwt = trailingWhitespace ? TextConstants.KeywordNone : this.scanner.PeekNullTypeSymbol();