Add repo.Reset() overload to allow replacing of index entries with commit entries

Fix #165

1 files changed, 156 insertions, 0 deletions

diff --git a/LibGit2Sharp.Tests/ResetHeadFixture.cs b/LibGit2Sharp.Tests/ResetHeadFixture.cs
new file mode 100644
index 00000000..44d43f06
--- /dev/null
+++ b/LibGit2Sharp.Tests/ResetHeadFixture.cs
@@ -0,0 +1,156 @@
+using System;
+using System.IO;
+using LibGit2Sharp.Tests.TestHelpers;
+using Xunit;
+using Xunit.Extensions;
+
+namespace LibGit2Sharp.Tests
+{
+    public class ResetHeadFixture : BaseFixture
+    {
+        [Theory]
+        [InlineData(true)]
+        [InlineData(false)]
+        public void ResetANewlyInitializedRepositoryThrows(bool isBare)
+        {
+            SelfCleaningDirectory scd = BuildSelfCleaningDirectory();
+
+            using (var repo = Repository.Init(scd.DirectoryPath, isBare))
+            {
+                Assert.Throws<LibGit2SharpException>(() => repo.Reset(ResetOptions.Soft));
+            }
+        }
+
+        [Fact]
+        public void SoftResetToTheHeadOfARepositoryDoesNotChangeTheTargetOfTheHead()
+        {
+            using (var repo = new Repository(BareTestRepoPath))
+            {
+                Branch oldHead = repo.Head;
+
+                repo.Reset(ResetOptions.Soft);
+
+                Assert.Equal(oldHead, repo.Head);
+            }
+        }
+
+        [Fact]
+        public void SoftResetSetsTheHeadToTheDereferencedCommitOfAChainedTag()
+        {
+            TemporaryCloneOfTestRepo path = BuildTemporaryCloneOfTestRepo();
+
+            using (var repo = new Repository(path.RepositoryPath))
+            {
+                Tag tag = repo.Tags["test"];
+                repo.Reset(ResetOptions.Soft, tag.CanonicalName);
+                Assert.Equal("e90810b8df3e80c413d903f631643c716887138d", repo.Head.Tip.Sha);
+            }
+        }
+
+        [Fact]
+        public void ResettingWithBadParamsThrows()
+        {
+            using (var repo = new Repository(BareTestRepoPath))
+            {
+                Assert.Throws<ArgumentNullException>(() => repo.Reset(ResetOptions.Soft, null));
+                Assert.Throws<ArgumentException>(() => repo.Reset(ResetOptions.Soft, ""));
+                Assert.Throws<LibGit2SharpException>(() => repo.Reset(ResetOptions.Soft, Constants.UnknownSha));
+            }
+        }
+
+        [Fact]
+        public void SoftResetSetsTheHeadToTheSpecifiedCommit()
+        {
+            /* Make the Head point to a branch through its name */
+            AssertSoftReset(b => b.Name, false, b => b.Name);
+        }
+
+        [Fact]
+        public void SoftResetSetsTheDetachedHeadToTheSpecifiedCommit()
+        {
+            /* Make the Head point to a commit through its sha (Detaches the Head) */
+            AssertSoftReset(b => b.Tip.Sha, true, b => "(no branch)");
+        }
+
+        private void AssertSoftReset(Func<Branch, string> branchIdentifierRetriever, bool shouldHeadBeDetached, Func<Branch, string> expectedHeadNameRetriever)
+        {
+            SelfCleaningDirectory scd = BuildSelfCleaningDirectory();
+
+            using (var repo = Repository.Init(scd.DirectoryPath)) 
+            {
+                FeedTheRepository(repo);
+
+                Tag tag = repo.Tags["mytag"];
+                Branch branch = repo.Branches["mybranch"];
+
+                string branchIdentifier = branchIdentifierRetriever(branch);
+                repo.Checkout(branchIdentifier);
+                Assert.Equal(shouldHeadBeDetached, repo.Info.IsHeadDetached);
+
+                string expectedHeadName = expectedHeadNameRetriever(branch);
+                Assert.Equal(expectedHeadName, repo.Head.Name);
+                Assert.Equal(branch.Tip.Sha, repo.Head.Tip.Sha);
+
+                /* Reset --soft the Head to a tag through its canonical name */
+                repo.Reset(ResetOptions.Soft, tag.CanonicalName);
+                Assert.Equal(expectedHeadName, repo.Head.Name);
+                Assert.Equal(tag.Target.Id, repo.Head.Tip.Id);
+
+                Assert.Equal(FileStatus.Staged, repo.Index.RetrieveStatus("a.txt"));
+
+                /* Reset --soft the Head to a commit through its sha */
+                repo.Reset(ResetOptions.Soft, branch.Tip.Sha);
+                Assert.Equal(expectedHeadName, repo.Head.Name);
+                Assert.Equal(branch.Tip.Sha, repo.Head.Tip.Sha);
+
+                Assert.Equal(FileStatus.Unaltered, repo.Index.RetrieveStatus("a.txt"));
+            }
+        }
+
+        private static void FeedTheRepository(Repository repo)
+        {
+            string fullPath = Path.Combine(repo.Info.WorkingDirectory, "a.txt");
+            File.WriteAllText(fullPath, "Hello\n");
+            repo.Index.Stage(fullPath);
+            repo.Commit("Initial commit", Constants.Signature, Constants.Signature);
+            repo.ApplyTag("mytag");
+
+            File.AppendAllText(fullPath, "World\n");
+            repo.Index.Stage(fullPath);
+
+            Signature shiftedSignature = Constants.Signature.TimeShift(TimeSpan.FromMinutes(1));
+            repo.Commit("Update file", shiftedSignature, shiftedSignature);
+            repo.CreateBranch("mybranch");
+
+            repo.Checkout("mybranch");
+
+            Assert.False(repo.Index.RetrieveStatus().IsDirty);
+        }
+
+        [Fact]
+        public void MixedResetRefreshesTheIndex()
+        {
+            SelfCleaningDirectory scd = BuildSelfCleaningDirectory();
+
+            using (var repo = Repository.Init(scd.DirectoryPath))
+            {
+                FeedTheRepository(repo);
+
+                Tag tag = repo.Tags["mytag"];
+
+                repo.Reset(ResetOptions.Mixed, tag.CanonicalName);
+
+                Assert.Equal(FileStatus.Modified, repo.Index.RetrieveStatus("a.txt"));
+            }
+        }
+
+        [Fact]
+        public void MixedResetInABareRepositoryThrows()
+        {
+            using (var repo = new Repository(BareTestRepoPath))
+            {
+                Assert.Throws<LibGit2SharpException>(() => repo.Reset(ResetOptions.Mixed));
+            }
+        }
+    }
+}