#32 - Year parser.

Author: techyian

readme.md

@@ -302,7 +302,7 @@ https://github.com/Apress/beg-sql-server-reporting-services/blob/master/Beginnin
 | Date & Time  | Today           | Complete      |                            |
 | Date & Time  | Weekday         | Complete      |                            |
 | Date & Time  | WeekdayName     | Complete      |                            |
-| Date & Time  | Year            | Not started   |                            |
+| Date & Time  | Year            | Complete      |                            |
 
 ### Math
 

src/ReportViewer.NET/Parsers/DateAndTime/YearParser.cs

@@ -0,0 +1,55 @@
+using ReportViewer.NET.DataObjects;
+using ReportViewer.NET.Extensions;
+using System;
+using System.Collections.Generic;
+using System.Text.RegularExpressions;
+
+namespace ReportViewer.NET.Parsers.DateAndTime
+{
+    public class YearParser : BaseParser
+    {
+        public static Regex YearRegex = RegexCommon.GenerateParserRegex("Year");
+
+        public YearParser(
+            string currentString,
+            ExpressionFieldOperator op,
+            ReportExpression currentExpression,
+            IEnumerable<IDictionary<string, object>> dataSetResults,
+            IDictionary<string, object> values,
+            int currentRowNumber,
+            IEnumerable<DataSet> dataSets,
+            DataSet activeDataset,
+            ReportRDL report
+        ) : base(currentString, op, currentExpression, dataSetResults, values, currentRowNumber, dataSets, activeDataset, YearRegex, report)
+        {
+        }
+
+        public override (Type, object) ExtractExpressionValue(string fieldName, string dataSetName)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override void Parse()
+        {
+            var match = YearRegex.Match(CurrentString);
+            var matchValue = match.Value;
+
+            // Remove the surrounding Day including open & close brace so we can inspect inner members and see if they too contain program flow expressions. 
+            matchValue = matchValue.MatchValueSubString(5);
+
+            var dtt = this.Report.Parser.ParseReportExpressionString(
+                matchValue,
+                this.DataSetResults,
+                this.Values,
+                this.CurrentRowNumber,
+                this.DataSets,
+                this.ActiveDataset,
+                null
+            ).ExpressionAsDateTime();
+
+            CurrentExpression.Index = match.Index;
+            CurrentExpression.ResolvedType = typeof(int);
+            CurrentExpression.Value = dtt.Year;
+        }
+    }
+}

src/ReportViewer.NET/Parsers/ExpressionFieldOperator.cs

@@ -72,6 +72,7 @@ public enum ExpressionFieldOperator
         Today,
         Weekday,
         WeekdayName,
+        Year,
         FormatCurrency,
         RowNumber
     }

src/ReportViewer.NET/Parsers/ExpressionParser.cs

@@ -659,6 +659,15 @@ ref string proposedString
                 weekdayNameParser.Parse();
                 proposedString = weekdayNameParser.GetProposedString();
             }
+
+            if (YearParser.YearRegex.IsMatch(currentString) &&
+                (currentExpression.Operator == ExpressionFieldOperator.None || YearParser.YearRegex.Match(currentString).Index < currentExpression.Index)
+            )
+            {
+                var yearParser = new YearParser(currentString, ExpressionFieldOperator.Year, currentExpression, dataSetResults, values, currentRowNumber, dataSets, activeDataset, _report);
+                yearParser.Parse();
+                proposedString = yearParser.GetProposedString();
+            }
         }
 
         private void SearchMathFunctions()

test/ReportViewer.NET.Tests/Parsers/DateAndTime/YearParserTests.cs

@@ -0,0 +1,64 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using ReportViewer.NET.DataObjects;
+using ReportViewer.NET.Extensions;
+using ReportViewer.NET.Parsers;
+
+namespace ReportViewer.NET.Tests.Parsers.DateAndTime
+{
+    [TestClass]
+    public class YearParserTests
+    {
+        private ExpressionParser _expressionParser;
+        private ReportRDL _report;
+
+        public YearParserTests()
+        {
+            var report = TestHelper.PrimeReport();
+
+            _report = report;
+            _expressionParser = new ExpressionParser(report);
+        }
+
+        [TestMethod]
+        public void Year_Returns_Integer()
+        {
+            // Arrange
+            var expr = "=Year(\"January 15, 2010 14:15:30\")";
+
+            // Act
+            var result = _expressionParser.ParseReportExpressionString(
+                expr,
+                null,
+                null,
+                1,
+                _report.DataSets,
+                null,
+                null
+            ).ExpressionAsInt();
+
+            // Assert
+            Assert.AreEqual(2010, result);
+        }
+
+        [TestMethod]
+        public void Day_Returns_Integer_Nested_DateAdd()
+        {
+            // Arrange
+            var expr = "=Year(DateAdd(\"yyyy\", 3, \"January 15, 2010 14:15:30\"))";
+
+            // Act
+            var result = _expressionParser.ParseReportExpressionString(
+                expr,
+                null,
+                null,
+                1,
+                _report.DataSets,
+                null,
+                null
+            ).ExpressionAsInt();
+
+            // Assert
+            Assert.AreEqual(2013, result);
+        }
+    }
+}