Find line end from GitHub URL

Author: jcansdale

src/GitHub.App/Services/GitHubContext.cs

@@ -12,5 +12,6 @@ public class GitHubContext
         public int? Issue { get; set; }
         public string Path { get; set; }
         public int? Line { get; set; }
+        public int? LineEnd { get; set; }
     }
 }

src/GitHub.App/Services/GitHubContextService.cs

@@ -35,7 +35,7 @@ public class GitHubContextService
         static readonly Regex windowTitlePathRegex = new Regex($"{path} at {branch} · {owner}/{repo}( · GitHub)? - ", RegexOptions.Compiled);
         static readonly Regex windowTitleBranchesRegex = new Regex($"Branches · {owner}/{repo}( · GitHub)? - ", RegexOptions.Compiled);
 
-        static readonly Regex urlLineRegex = new Regex($"#L(?<line>[0-9]+)$", RegexOptions.Compiled);
+        static readonly Regex urlLineRegex = new Regex($"#L(?<line>[0-9]+)(-L(?<lineEnd>[0-9]+))?$", RegexOptions.Compiled);
 
         public GitHubContext FindContextFromUrl(string url)
         {
@@ -50,14 +50,16 @@ public GitHubContext FindContextFromUrl(string url)
                 return null;
             }
 
+            var (line, lineEnd) = FindLine(uri);
             return new GitHubContext
             {
                 Host = uri.Host,
                 Owner = uri.Owner,
                 RepositoryName = uri.RepositoryName,
                 Path = FindPath(uri),
                 PullRequest = FindPullRequest(uri),
-                Line = FindLine(uri)
+                Line = line,
+                LineEnd = lineEnd
             };
         }
 
@@ -158,18 +160,26 @@ public GitHubContext FindContextFromWindowTitle(string windowTitle)
         }
 
 
-        static int? FindLine(UriString gitHubUrl)
+        static (int? lineStart, int? lineEnd) FindLine(UriString gitHubUrl)
         {
             var url = gitHubUrl.ToString();
 
             var match = urlLineRegex.Match(url);
             if (match.Success)
             {
                 int.TryParse(match.Groups["line"].Value, out int line);
-                return line;
+
+                var lineEndGroup = match.Groups["lineEnd"];
+                if (string.IsNullOrEmpty(lineEndGroup.Value))
+                {
+                    return (line, null);
+                }
+
+                int.TryParse(lineEndGroup.Value, out int lineEnd);
+                return (line, lineEnd);
             }
 
-            return null;
+            return (null, null);
         }
 
         string FindPath(UriString uri)

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

@@ -104,6 +104,19 @@ public void Line(string url, int? expectLine)
             Assert.That(context.Line, Is.EqualTo(expectLine));
         }
 
+        [TestCase("https://github.com/github/VisualStudio", null, null)]
+        [TestCase("https://github.com/github/VisualStudio/blob/master/Code.cs#L115", 115, null)]
+        [TestCase("https://github.com/github/VisualStudio/blob/master/Code.cs#L115-L116", 115, 116)]
+        public void LineEnd(string url, int? expectLine, int? expectLineEnd)
+        {
+            var target = new GitHubContextService();
+
+            var context = target.FindContextFromUrl(url);
+
+            Assert.That(context.Line, Is.EqualTo(expectLine));
+            Assert.That(context.LineEnd, Is.EqualTo(expectLineEnd));
+        }
+
         [TestCase("foo", true)]
         [TestCase("ssh://[email protected]:443/benstraub/libgit2", true)]
         [TestCase("https://github.com/github/VisualStudio", false)]