Expose low level Index.Add()

Author: nulltoken

LibGit2Sharp.Tests/IndexFixture.cs

@@ -392,5 +392,37 @@ public void CanRemoveAnEntryFromTheIndex(string pathInTheIndex, FileStatus expec
                 Assert.Equal(expectedAfterStatus, after);
             }
         }
+
+        [Theory]
+        [InlineData("new_untracked_file.txt", FileStatus.Untracked, FileStatus.Added)]
+        [InlineData("modified_unstaged_file.txt", FileStatus.Modified, FileStatus.Staged)]
+        public void CanAddAnEntryToTheIndexFromAFileInTheWorkdir(string pathInTheWorkdir, FileStatus expectedBeforeStatus, FileStatus expectedAfterStatus)
+        {
+            var path = SandboxStandardTestRepoGitDir();
+            using (var repo = new Repository(path))
+            {
+                var before = repo.RetrieveStatus(pathInTheWorkdir);
+                Assert.Equal(expectedBeforeStatus, before);
+
+                repo.Index.Add(pathInTheWorkdir);
+
+                var after = repo.RetrieveStatus(pathInTheWorkdir);
+                Assert.Equal(expectedAfterStatus, after);
+            }
+        }
+
+        [Fact]
+        public void AddingAnEntryToTheIndexFromAUnknwonFileInTheWorkdirThrows()
+        {
+            var path = SandboxStandardTestRepoGitDir();
+            using (var repo = new Repository(path))
+            {
+                const string filePath = "i_dont_exist.txt";
+                var before = repo.RetrieveStatus(filePath);
+                Assert.Equal(FileStatus.Nonexistent, before);
+
+                Assert.Throws<NotFoundException>(() => repo.Index.Add(filePath));
+            }
+        }
     }
 }

LibGit2Sharp/Index.cs

@@ -178,6 +178,26 @@ public virtual void Remove(string indexEntryPath)
             UpdatePhysicalIndex();
         }
 
+        /// <summary>
+        /// Adds a file from the workdir in the <see cref="Index"/>.
+        /// <para>
+        ///   If an entry with the same path already exists in the <see cref="Index"/>,
+        ///   the newly added one will overwrite it.
+        /// </para>
+        /// </summary>
+        /// <param name="pathInTheWorkdir">The path, in the working directory, of the file to be added.</param>
+        public virtual void Add(string pathInTheWorkdir)
+        {
+            if (pathInTheWorkdir == null)
+            {
+                throw new ArgumentNullException("pathInTheWorkdir");
+            }
+
+            Proxy.git_index_add_bypath(handle, pathInTheWorkdir);
+
+            UpdatePhysicalIndex();
+        }
+
         private void UpdatePhysicalIndex()
         {
             Proxy.git_index_write(handle);