Merge pull request #184 from spreadsheetlab/fix-issue-183

Fix: exception for parser references of special ranges

Author: joerivv

src/XLParser.Tests/FormulaAnalysisTest.cs

@@ -1212,6 +1212,44 @@ public void AbsoluteRowReference()
             Assert.AreEqual("$1", references.First().MaxLocation);
         }
 
+        [TestMethod]
+        public void RefError()
+        {
+            List<ParserReference> references = new FormulaAnalyzer("#REF!").ParserReferences().ToList();
+
+            Assert.AreEqual(1, references.Count);
+            Assert.AreEqual(ReferenceType.RefError, references.First().ReferenceType);
+            Assert.AreEqual("#REF!", references.First().LocationString);
+        }
+
+        [TestMethod]
+        public void RefErrorRange()
+        {
+            List<ParserReference> references = new FormulaAnalyzer("#REF!:#REF!").ParserReferences().ToList();
+
+            Assert.AreEqual(2, references.Count);
+            Assert.AreEqual("#REF!", references.First().LocationString);
+            Assert.AreEqual("#REF!", references.Last().LocationString);
+        }
+
+        [TestMethod]
+        public void RefErrorCellRange()
+        {
+            List<ParserReference> references = new FormulaAnalyzer("A1:#REF!").ParserReferences().ToList();
+
+            Assert.AreEqual(2, references.Count);
+            Assert.AreEqual("A1", references.First().LocationString);
+            Assert.AreEqual("#REF!", references.Last().LocationString);
+        }
+
+        [TestMethod]
+        public void IndirectFunctionRange()
+        {
+            List<ParserReference> references = new FormulaAnalyzer(@"INDIRECT(""A3""):INDIRECT(""A20000"")").ParserReferences().ToList();
+
+            Assert.AreEqual(0, references.Count);
+        }
+
         [TestMethod]
         public void ReferenceFunctionAsArgument()
         {

src/XLParser/ExcelFormulaParser.cs

@@ -415,6 +415,7 @@ public static IEnumerable<ParserReference> GetParserReferences(this ParseTreeNod
                 case GrammarNames.HorizontalRange:
                 case GrammarNames.VerticalRange:
                 case GrammarNames.StructuredReference:
+                case GrammarNames.RefError:
                     list.Add(new ParserReference(node));
                     break;
                 case GrammarNames.Reference:
@@ -424,9 +425,9 @@ public static IEnumerable<ParserReference> GetParserReferences(this ParseTreeNod
                 default:
                     if (node.IsRange())
                     {
-                        var rangeStart = GetParserReferences(node.ChildNodes[0].SkipToRelevant()).First();
-                        var rangeEnd = GetParserReferences(node.ChildNodes[2].SkipToRelevant()).First();
-                        if (rangeStart.ReferenceType == ReferenceType.Cell && rangeEnd.ReferenceType == ReferenceType.Cell)
+                        var rangeStart = GetParserReferences(node.ChildNodes[0]).FirstOrDefault();
+                        var rangeEnd = GetParserReferences(node.ChildNodes[2]).FirstOrDefault();
+                        if (rangeStart?.ReferenceType == ReferenceType.Cell && rangeEnd?.ReferenceType == ReferenceType.Cell)
                         {
                             ParserReference range = rangeStart;
                             range.MaxLocation = rangeEnd.MinLocation;
@@ -436,7 +437,7 @@ public static IEnumerable<ParserReference> GetParserReferences(this ParseTreeNod
                             list.Add(range);
                             break;
                         }
-                        if (rangeStart.ReferenceType == ReferenceType.Table && rangeEnd.ReferenceType == ReferenceType.Table && rangeStart.Name == rangeEnd.Name && rangeStart.TableColumns.Length == 1 && rangeEnd.TableColumns.Length == 1)
+                        if (rangeStart?.ReferenceType == ReferenceType.Table && rangeEnd?.ReferenceType == ReferenceType.Table && rangeStart.Name == rangeEnd.Name && rangeStart.TableColumns.Length == 1 && rangeEnd.TableColumns.Length == 1)
                         {
                             ParserReference range = rangeStart;
                             range.TableColumns = rangeStart.TableColumns.Concat(rangeEnd.TableColumns).ToArray();