Add unit tests for FindNearestMatchingLine

Author: jcansdale

src/GitHub.App/Services/NavigationService.cs

@@ -54,32 +54,7 @@ public IVsTextView FindActiveView()
             return hresult == VSConstants.S_OK ? view : null;
         }
 
-        string GetText(IVsTextView textView)
-        {
-            IVsTextLines buffer;
-            ErrorHandler.ThrowOnFailure(textView.GetBuffer(out buffer));
-
-            int line;
-            int index;
-            ErrorHandler.ThrowOnFailure(buffer.GetLastLineIndex(out line, out index));
-
-            string text;
-            ErrorHandler.ThrowOnFailure(buffer.GetLineText(0, 0, line, index, out text));
-            return text;
-        }
-
-        IVsTextView OpenDocument(string fullPath)
-        {
-            var logicalView = VSConstants.LOGVIEWID.TextView_guid;
-            IVsUIHierarchy hierarchy;
-            uint itemID;
-            IVsWindowFrame windowFrame;
-            IVsTextView view;
-            VsShellUtilities.OpenDocument(serviceProvider, fullPath, logicalView, out hierarchy, out itemID, out windowFrame, out view);
-            return view;
-        }
-
-        static int FindNearestMatchingLine(IList<string> fromLines, IList<string> toLines, int line)
+        public int FindNearestMatchingLine(IList<string> fromLines, IList<string> toLines, int line)
         {
             line = line < fromLines.Count ? line : fromLines.Count - 1; // VS shows one extra line at end
             var fromLine = fromLines[line];
@@ -107,6 +82,31 @@ static int FindNearestMatchingLine(IList<string> fromLines, IList<string> toLine
             }
         }
 
+        string GetText(IVsTextView textView)
+        {
+            IVsTextLines buffer;
+            ErrorHandler.ThrowOnFailure(textView.GetBuffer(out buffer));
+
+            int line;
+            int index;
+            ErrorHandler.ThrowOnFailure(buffer.GetLastLineIndex(out line, out index));
+
+            string text;
+            ErrorHandler.ThrowOnFailure(buffer.GetLineText(0, 0, line, index, out text));
+            return text;
+        }
+
+        IVsTextView OpenDocument(string fullPath)
+        {
+            var logicalView = VSConstants.LOGVIEWID.TextView_guid;
+            IVsUIHierarchy hierarchy;
+            uint itemID;
+            IVsWindowFrame windowFrame;
+            IVsTextView view;
+            VsShellUtilities.OpenDocument(serviceProvider, fullPath, logicalView, out hierarchy, out itemID, out windowFrame, out view);
+            return view;
+        }
+
         static IList<string> ReadLines(string text)
         {
             var lines = new List<string>();

test/UnitTests/GitHub.App/Services/NavigationServiceTests.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using GitHub.Services;
+using NUnit.Framework;
+using NSubstitute;
+
+public class NavigationServiceTests
+{
+    public class TheFindNearestMatchingLineMethod
+    {
+        [TestCase(new[] { "line" }, new[] { "line" }, 0, 0, Description = "Match same line")]
+        [TestCase(new[] { "line" }, new[] { "line_no_match" }, 0, -1, Description = "No matching line")]
+        [TestCase(new[] { "line" }, new[] { "", "line" }, 0, 1, Description = "Match line moved up")]
+        [TestCase(new[] { "", "line" }, new[] { "line" }, 1, 0, Description = "Match line moved down")]
+        [TestCase(new[] { "line", "line" }, new[] { "line", "line" }, 0, 0, Description = "Match nearest line")]
+        [TestCase(new[] { "line", "line" }, new[] { "line", "line" }, 1, 1, Description = "Match nearest line")]
+        [TestCase(new[] { "line" }, new[] { "line" }, 1, 0, Description = "Treat after last line the same as last line")]
+        public void FindNearestMatching(IList<string> fromLines, IList<string> toLines, int line, int expectLine)
+        {
+            var sp = Substitute.For<IServiceProvider>();
+            var target = new NavigationService(sp);
+
+            var matchingLine = target.FindNearestMatchingLine(fromLines, toLines, line);
+
+            Assert.That(matchingLine, Is.EqualTo(expectLine));
+        }
+    }
+}

test/UnitTests/UnitTests.csproj

@@ -234,6 +234,7 @@
     <Compile Include="GitHub.App\Models\RepositoryModelTests.cs" />
     <Compile Include="GitHub.App\Services\AvatarProviderTests.cs" />
     <Compile Include="GitHub.App\Services\GitClientTests.cs" />
+    <Compile Include="GitHub.App\Services\NavigationServiceTests.cs" />
     <Compile Include="GitHub.App\Services\OAuthCallbackListenerTests.cs" />
     <Compile Include="GitHub.App\Services\PullRequestServiceTests.cs" />
     <Compile Include="GitHub.App\Services\RepositoryCloneServiceTests.cs" />