BaseFixture: easy creation of a config-isolated repository

We should try to keep the user's configuration away from the tests as it
may affect what the code ends up doing. To that effect,
InitIsolatedRepository() returns a Repository with some dummy
configuration.

This includes moving the fetch tests over to this.

Author: carlosmn

LibGit2Sharp.Tests/FetchFixture.cs

@@ -16,9 +16,7 @@ public class FetchFixture : BaseFixture
         [InlineData("git://github.com/libgit2/TestGitRepository.git")]
         public void CanFetchIntoAnEmptyRepository(string url)
         {
-            string repoPath = InitNewRepository();
-
-            using (var repo = new Repository(repoPath))
+            using (var repo = InitIsolatedRepository())
             {
                 Remote remote = repo.Network.Remotes.Add(remoteName, url);
 
@@ -55,9 +53,7 @@ public void CanFetchIntoAnEmptyRepositoryWithCredentials()
             InconclusiveIf(() => string.IsNullOrEmpty(Constants.PrivateRepoUrl),
                 "Populate Constants.PrivateRepo* to run this test");
 
-            string repoPath = InitNewRepository();
-
-            using (var repo = new Repository(repoPath))
+            using (var repo = InitIsolatedRepository())
             {
                 Remote remote = repo.Network.Remotes.Add(remoteName, Constants.PrivateRepoUrl);
 
@@ -79,9 +75,7 @@ public void CanFetchIntoAnEmptyRepositoryWithCredentials()
         [InlineData("git://github.com/libgit2/TestGitRepository.git")]
         public void CanFetchAllTagsIntoAnEmptyRepository(string url)
         {
-            string repoPath = InitNewRepository();
-
-            using (var repo = new Repository(repoPath))
+            using (var repo = InitIsolatedRepository())
             {
                 Remote remote = repo.Network.Remotes.Add(remoteName, url);
 
@@ -116,9 +110,7 @@ public void CanFetchAllTagsIntoAnEmptyRepository(string url)
         [InlineData("git://github.com/libgit2/TestGitRepository.git", "master", "first-merge")]
         public void CanFetchCustomRefSpecsIntoAnEmptyRepository(string url, string localBranchName, string remoteBranchName)
         {
-            string repoPath = InitNewRepository();
-
-            using (var repo = new Repository(repoPath))
+            using (var repo = InitIsolatedRepository())
             {
                 Remote remote = repo.Network.Remotes.Add(remoteName, url);
 
@@ -153,9 +145,7 @@ public void FetchRespectsConfiguredAutoTagSetting(TagFetchMode tagFetchMode, int
         {
             string url = "http://github.com/libgit2/TestGitRepository";
 
-            string repoPath = InitNewRepository();
-
-            using (var repo = new Repository(repoPath))
+            using (var repo = InitIsolatedRepository())
             {
                 Remote remote = repo.Network.Remotes.Add(remoteName, url);
                 Assert.NotNull(remote);

LibGit2Sharp.Tests/TestHelpers/BaseFixture.cs

@@ -154,6 +154,11 @@ protected string InitNewRepository(bool isBare = false)
             return Repository.Init(scd.DirectoryPath, isBare);
         }
 
+        protected Repository InitIsolatedRepository(bool isBare = false)
+        {
+            return new Repository(InitNewRepository(), options: BuildFakeConfigs(BuildSelfCleaningDirectory()));
+        }
+
         public void Register(string directoryPath)
         {
             directories.Add(directoryPath);