Detect github.my-company-server.com as GitHub

src/shared/GitHub.Tests/GitHubHostProviderTests.cs

@@ -30,10 +30,26 @@ public void GitHubHostProvider_IsGitHubDotCom(string input, bool expected)
         // show a helpful error message in the call to `GenerateCredentialAsync` instead.
         [InlineData("http://github.com", true)]
         [InlineData("http://gist.github.com", true)]
-        [InlineData("https://github.com", true)]
-        [InlineData("https://gist.github.com", true)]
         [InlineData("ssh://github.com", false)]
         [InlineData("https://example.com", false)]
+
+        [InlineData("https://github.com", true)]
+        [InlineData("https://github.con", false)] // No support of phony similar tld.
+        [InlineData("https://gist.github.con", false)] // No support of phony similar tld.
+        [InlineData("https://foogithub.com", false)] // No support of non github.com domains.
+        [InlineData("https://api.github.com", false)] // No support of github.com subdomains.
+        [InlineData("https://gist.github.com", true)] // Except gists.
+
+        [InlineData("http://github.my-company-server.com", true)]
+        [InlineData("http://gist.github.my-company-server.com", true)]
+        [InlineData("https://github.my-company-server.com", true)]
+        [InlineData("https://gist.github.my-company-server.com", true)]
+        [InlineData("https://gist.my-company-server.com", false)]
+        [InlineData("https://my-company-server.com", false)]
+        [InlineData("https://github.my.company.server.com", true)]
+        [InlineData("https://foogithub.my-company-server.com", false)]
+        [InlineData("https://api.github.my-company-server.com", false)]
+        [InlineData("https://gist.github.my.company.server.com", true)]
         public void GitHubHostProvider_IsSupported(string uriString, bool expected)
         {
             Uri uri = new Uri(uriString);
@@ -55,6 +71,10 @@ public void GitHubHostProvider_IsSupported(string uriString, bool expected)
         [Theory]
         [InlineData("https://github.com", "https://github.com")]
         [InlineData("https://gist.github.com", "https://github.com")]
+        [InlineData("https://github.my-company-server.com", "https://github.my-company-server.com")]
+        [InlineData("https://gist.github.my-company-server.com", "https://github.my-company-server.com")]
+        [InlineData("https://github.my.company.server.com", "https://github.my.company.server.com")]
+        [InlineData("https://gist.github.my.company.server.com", "https://github.my.company.server.com")]
         public void GitHubHostProvider_GetCredentialServiceUrl(string uriString, string expectedService)
         {
             Uri uri = new Uri(uriString);

src/shared/GitHub/GitHubHostProvider.cs

@@ -52,16 +52,35 @@ public override bool IsSupported(InputArguments input)
                 return false;
             }
 
-            // Split port number and hostname from host input argument
-            input.TryGetHostAndPort(out string hostName, out _);
-
             // We do not support unencrypted HTTP communications to GitHub,
             // but we report `true` here for HTTP so that we can show a helpful
             // error message for the user in `CreateCredentialAsync`.
-            return (StringComparer.OrdinalIgnoreCase.Equals(input.Protocol, "http") ||
-                    StringComparer.OrdinalIgnoreCase.Equals(input.Protocol, "https")) &&
-                   (StringComparer.OrdinalIgnoreCase.Equals(hostName, GitHubConstants.GitHubBaseUrlHost) ||
-                    StringComparer.OrdinalIgnoreCase.Equals(hostName, GitHubConstants.GistBaseUrlHost));
+            if (!StringComparer.OrdinalIgnoreCase.Equals(input.Protocol, "http") &&
+                !StringComparer.OrdinalIgnoreCase.Equals(input.Protocol, "https"))
+            {
+                return false;
+            }
+
+            // Split port number and hostname from host input argument
+            input.TryGetHostAndPort(out string hostName, out _);
+
+            if (StringComparer.OrdinalIgnoreCase.Equals(hostName, GitHubConstants.GitHubBaseUrlHost) ||
+                StringComparer.OrdinalIgnoreCase.Equals(hostName, GitHubConstants.GistBaseUrlHost))
+            {
+                return true;
+            }
+
+            string[] domains = hostName.Split(new char[] { '.' });
+
+            // github[.subdomain].domain.tld
+            if (domains.Length >= 3 && domains[0] == "github")
+                return true;
+
+            // gist.github[.subdomain].domain.tld
+            if (domains.Length >= 4 && domains[0] == "gist" && domains[1] == "github")
+                return true;
+
+            return false;
         }
 
         public override string GetServiceName(InputArguments input)
@@ -264,10 +283,11 @@ private static Uri NormalizeUri(Uri uri)
             }
 
             // Special case for gist.github.com which are git backed repositories under the hood.
-            // Credentials for these repositories are the same as the one stored with "github.com"
-            if (uri.DnsSafeHost.Equals(GitHubConstants.GistBaseUrlHost, StringComparison.OrdinalIgnoreCase))
-            {
-                return new Uri("https://" + GitHubConstants.GitHubBaseUrlHost);
+            // Credentials for these repositories are the same as the one stored with "github.com".
+            // Same for gist.github[.subdomain].domain.tld. The general form was already checked via IsSupported.
+            int firstDot = uri.DnsSafeHost.IndexOf(".");
+            if (uri.DnsSafeHost.Substring(0, firstDot).Equals("gist", StringComparison.OrdinalIgnoreCase)) {
+                return new Uri("https://" + uri.DnsSafeHost.Substring(firstDot+1));
             }
 
             return uri;