Throws when HEAD is missing

nulltoken · nulltoken · commit 3e6563007178 · 2013-03-01T10:18:36.000+01:00
Fix libgit2#351
diff --git a/LibGit2Sharp.Tests/RepositoryFixture.cs b/LibGit2Sharp.Tests/RepositoryFixture.cs
@@ -502,5 +502,20 @@ public void CanReadRepositoryMessage()
                 Assert.Equal(testMessage, repo.Info.Message);
             }
         }
+
+        [Fact]
+        public void AccessingADeletedHeadThrows()
+        {
+            SelfCleaningDirectory scd = BuildSelfCleaningDirectory();
+
+            using (var repo = Repository.Init(scd.DirectoryPath))
+            {
+                Assert.NotNull(repo.Head);
+
+                File.Delete(Path.Combine(repo.Info.Path, "HEAD"));
+
+                Assert.Throws<LibGit2SharpException>(() => repo.Head);
+            }
+        }
     }
 }
diff --git a/LibGit2Sharp/Repository.cs b/LibGit2Sharp/Repository.cs
@@ -164,6 +164,11 @@ public Branch Head
             {
                 Reference reference = Refs.Head;
 
+                if (reference == null)
+                {
+                    throw new LibGit2SharpException("Corrupt repository. The 'HEAD' reference is missing.");
+                }
+
                 if (reference is SymbolicReference)
                 {
                     return new Branch(this, reference);

Original file line number	Diff line number	Diff line change
`@@ -502,5 +502,20 @@ public void CanReadRepositoryMessage()`
`502`	`502`	`Assert.Equal(testMessage, repo.Info.Message);`
`503`	`503`	`}`
`504`	`504`	`}`
	`505`	`+`
	`506`	`+ [Fact]`
	`507`	`+ public void AccessingADeletedHeadThrows()`
	`508`	`+ {`
	`509`	`+ SelfCleaningDirectory scd = BuildSelfCleaningDirectory();`
	`510`	`+`
	`511`	`+ using (var repo = Repository.Init(scd.DirectoryPath))`
	`512`	`+ {`
	`513`	`+ Assert.NotNull(repo.Head);`
	`514`	`+`
	`515`	`+ File.Delete(Path.Combine(repo.Info.Path, "HEAD"));`
	`516`	`+`
	`517`	`+ Assert.Throws<LibGit2SharpException>(() => repo.Head);`
	`518`	`+ }`
	`519`	`+ }`
`505`	`520`	`}`
`506`	`521`	`}`
Original file line number	Diff line number	Diff line change
`@@ -164,6 +164,11 @@ public Branch Head`
`164`	`164`	`{`
`165`	`165`	`Reference reference = Refs.Head;`
`166`	`166`
	`167`	`+ if (reference == null)`
	`168`	`+ {`
	`169`	`+ throw new LibGit2SharpException("Corrupt repository. The 'HEAD' reference is missing.");`
	`170`	`+ }`
	`171`	`+`
`167`	`172`	`if (reference is SymbolicReference)`
`168`	`173`	`{`
`169`	`174`	`return new Branch(this, reference);`