Add Stashes.Remove

LibGit2Sharp.Tests/StashFixture.cs

@@ -3,6 +3,7 @@
 using System.Linq;
 using LibGit2Sharp.Tests.TestHelpers;
 using Xunit;
+using Xunit.Extensions;
 
 namespace LibGit2Sharp.Tests
 {
@@ -21,7 +22,7 @@ public void CannotAddStashAgainstBareRepository()
         }
 
         [Fact]
-        public void CanAddStash()
+        public void CanAddAndRemoveStash()
         {
             TemporaryCloneOfTestRepo path = BuildTemporaryCloneOfTestRepo(StandardTestRepoWorkingDirPath);
             using (var repo = new Repository(path.RepositoryPath))
@@ -61,6 +62,17 @@ public void CanAddStash()
                 // Stash history has been shifted
                 Assert.Equal(repo.Lookup<Commit>("stash@{0}").Sha, secondStash.Target.Sha);
                 Assert.Equal(repo.Lookup<Commit>("stash@{1}").Sha, stash.Target.Sha);
+
+                //Remove one stash
+                repo.Stashes.Remove("stash@{0}");
+                Assert.Equal(1, repo.Stashes.Count());
+                Stash newTopStash = repo.Stashes.First();
+                Assert.Equal("stash@{0}", newTopStash.CanonicalName);
+                Assert.Equal(stash.Target.Sha, newTopStash.Target.Sha);
+
+                // Stash history has been shifted
+                Assert.Equal(stash.Target.Sha, repo.Lookup<Commit>("stash").Sha);
+                Assert.Equal(stash.Target.Sha, repo.Lookup<Commit>("stash@{0}").Sha);
             }
         }
 
@@ -183,5 +195,19 @@ public void CanStashIgnoredFiles()
                 Assert.NotNull(blob);
             }
         }
+
+        [Theory]
+        [InlineData("stah@{0}")]
+        [InlineData("stash@{0")]
+        [InlineData("stash@{fake}")]
+        [InlineData("dummy")]
+        public void RemovingStashWithBadParamShouldThrow(string stashRefLog)
+        {
+            TemporaryCloneOfTestRepo path = BuildTemporaryCloneOfTestRepo(StandardTestRepoWorkingDirPath);
+            using (var repo = new Repository(path.RepositoryPath))
+            {
+                Assert.Throws<ArgumentException>(() => repo.Stashes.Remove(stashRefLog));
+            }
+        }
     }
 }

LibGit2Sharp/Core/NativeMethods.cs

@@ -953,6 +953,9 @@ internal static extern int git_stash_foreach(
             git_stash_cb callback,
             IntPtr payload);
 
+        [DllImport(libgit2)]
+        internal static extern int git_stash_drop(RepositorySafeHandle repo, UIntPtr index);
+
         [DllImport(libgit2)]
         internal static extern int git_status_file(
             out FileStatus statusflags,

LibGit2Sharp/Core/Proxy.cs

@@ -1801,6 +1801,15 @@ public static ICollection<TResult> git_stash_foreach<TResult>(
                 GitErrorCode.NotFound);
         }
 
+        public static void git_stash_drop(RepositorySafeHandle repo, int index)
+        {
+            using (ThreadAffinity())
+            {
+                int res = NativeMethods.git_stash_drop(repo, (UIntPtr) index);
+                Ensure.BooleanResult(res);
+            }
+        }
+
         #endregion
 
         #region git_status_

LibGit2Sharp/StashCollection.cs

@@ -1,4 +1,5 @@
-using System.Collections;
+using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Globalization;
@@ -77,6 +78,42 @@ public virtual Stash Add(Signature stasher, string message = null, StashOptions
             return new Stash(repo, oid, 0);
         }
 
+        /// <summary>
+        ///   Remove a single stashed state from the stash list.
+        /// </summary>
+        /// <param name = "stashRefLog">The log reference of the stash to delete. Pattern is "stash@{i}" where i is the index of the stash to remove</param>
+        public virtual void Remove(string stashRefLog)
+        {
+            Ensure.ArgumentNotNullOrEmptyString(stashRefLog, "stashRefLog");
+
+            int index;
+            if(!TryExtractStashIndexFromRefLog(stashRefLog, out index) || index < 0)
+            {
+                throw new ArgumentException("must be a valid stash log reference. Pattern is 'stash@{i}' where 'i' is an integer", "stashRefLog");
+            }
+
+            Proxy.git_stash_drop(repo.Handle, index);
+        }
+
+        private static bool TryExtractStashIndexFromRefLog(string stashRefLog, out int index)
+        {
+            index = -1;
+
+            if (!stashRefLog.StartsWith("stash@{"))
+            {
+                return false;
+            }
+
+            if (!stashRefLog.EndsWith("}"))
+            {
+                return false;
+            }
+
+            var indexAsString = stashRefLog.Substring(7, stashRefLog.Length - 8);
+
+            return int.TryParse(indexAsString, out index);
+        }
+
         private string DebuggerDisplay
         {
             get