Merge pull request #1519 from libgit2/ethomson/tree_entries_by_id

TreeDefinition: allow `Add` a blob by ID

Author: ethomson

LibGit2Sharp.Tests/TreeDefinitionFixture.cs

@@ -266,6 +266,49 @@ public void CanAddAnExistingBlob(string blobSha, string targetPath)
             }
         }
 
+        [Theory]
+        [InlineData("a8233120f6ad708f843d861ce2b7228ec4e3dec6", "README_TOO")]
+        [InlineData("a8233120f6ad708f843d861ce2b7228ec4e3dec6", "1/README")]
+        [InlineData("45b983be36b73c0788dc9cbcb76cbb80fc7bb057", "1/another_one.txt")]
+        [InlineData("45b983be36b73c0788dc9cbcb76cbb80fc7bb057", "another_one.txt")]
+        public void CanAddBlobById(string blobSha, string targetPath)
+        {
+            string path = SandboxBareTestRepo();
+            using (var repo = new Repository(path))
+            {
+                TreeDefinition td = TreeDefinition.From(repo.Head.Tip.Tree);
+                Assert.Null(td[targetPath]);
+
+                var objectId = new ObjectId(blobSha);
+
+                td.Add(targetPath, objectId, Mode.NonExecutableFile);
+
+                TreeEntryDefinition fetched = td[targetPath];
+                Assert.NotNull(fetched);
+
+                Assert.Equal(objectId, fetched.TargetId);
+                Assert.Equal(Mode.NonExecutableFile, fetched.Mode);
+            }
+        }
+
+        [Fact]
+        public void CannotAddTreeById()
+        {
+            const string treeSha = "7f76480d939dc401415927ea7ef25c676b8ddb8f";
+            const string targetPath = "1/2";
+
+            string path = SandboxBareTestRepo();
+            using (var repo = new Repository(path))
+            {
+                TreeDefinition td = TreeDefinition.From(repo.Head.Tip.Tree);
+                Assert.Null(td[targetPath]);
+
+                var objectId = new ObjectId(treeSha);
+
+                Assert.Throws<ArgumentException>(() => td.Add(targetPath, objectId, Mode.Directory));
+            }
+        }
+
         [Fact]
         public void CanAddAnExistingSubmodule()
         {

LibGit2Sharp/TreeDefinition.cs

@@ -201,6 +201,23 @@ public virtual TreeDefinition Add(string targetTreeEntryPath, string filePath, M
             return Add(targetTreeEntryPath, ted);
         }
 
+        /// <summary>
+        /// Adds or replaces a <see cref="TreeEntryDefinition"/> from an existing blob specified by its Object ID at the specified <paramref name="targetTreeEntryPath"/> location.
+        /// </summary>
+        /// <param name="targetTreeEntryPath">The path within this <see cref="TreeDefinition"/>.</param>
+        /// <param name="id">The object ID for this entry.</param>
+        /// <param name="mode">The file related <see cref="Mode"/> attributes.</param>
+        /// <returns>The current <see cref="TreeDefinition"/>.</returns>
+        public virtual TreeDefinition Add(string targetTreeEntryPath, ObjectId id, Mode mode)
+        {
+            Ensure.ArgumentNotNull(id, "id");
+            Ensure.ArgumentConformsTo(mode, m => m.HasAny(TreeEntryDefinition.BlobModes), "mode");
+
+            TreeEntryDefinition ted = TreeEntryDefinition.From(id, mode);
+
+            return Add(targetTreeEntryPath, ted);
+        }
+
         /// <summary>
         /// Adds or replaces a <see cref="TreeEntryDefinition"/>, dynamically built from the provided <see cref="Tree"/>, at the specified <paramref name="targetTreeEntryPath"/> location.
         /// </summary>

LibGit2Sharp/TreeEntryDefinition.cs

@@ -54,6 +54,8 @@ internal static TreeEntryDefinition From(TreeEntry treeEntry)
 
         internal static TreeEntryDefinition From(Blob blob, Mode mode)
         {
+            Ensure.ArgumentNotNull(blob, "blob");
+
             return new TreeEntryDefinition
             {
                 Mode = mode,
@@ -63,6 +65,19 @@ internal static TreeEntryDefinition From(Blob blob, Mode mode)
             };
         }
 
+        internal static TreeEntryDefinition From(ObjectId id, Mode mode)
+        {
+            Ensure.ArgumentNotNull(id, "id");
+            Ensure.ArgumentNotNull(mode, "mode");
+
+            return new TreeEntryDefinition
+            {
+                Mode = mode,
+                TargetType = TreeEntryTargetType.Blob,
+                TargetId = id
+            };
+        }
+
         internal static TreeEntryDefinition TransientBlobFrom(string filePath, Mode mode)
         {
             Ensure.ArgumentConformsTo(mode, m => m.HasAny(BlobModes), "mode");