Improve listing performance by using go-git (#6478)

* Use go-git for tree reading and commit info lookup.

Signed-off-by: Filip Navara <navara@emclient.com>

* Use TreeEntry.IsRegular() instead of ObjectType that was removed.

Signed-off-by: Filip Navara <navara@emclient.com>

* Use the treePath to optimize commit info search.

Signed-off-by: Filip Navara <navara@emclient.com>

* Extract the latest commit at treePath along with the other commits.

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix listing commit info for a directory that was created in one commit and never modified after.

Signed-off-by: Filip Navara <navara@emclient.com>

* Avoid nearly all external 'git' invocations when doing directory listing (.editorconfig code path is still hit).

Signed-off-by: Filip Navara <navara@emclient.com>

* Use go-git for reading blobs.

Signed-off-by: Filip Navara <navara@emclient.com>

* Make SHA1 type alias for plumbing.Hash in go-git.

Signed-off-by: Filip Navara <navara@emclient.com>

* Make Signature type alias for object.Signature in go-git.

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix GetCommitsInfo for repository with only one commit.

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix PGP signature verification.

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix issues with walking commit graph across merges.

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix typo in condition.

Signed-off-by: Filip Navara <navara@emclient.com>

* Speed up loading branch list by keeping the repository reference (and thus all the loaded packfile indexes).

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix lising submodules.

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix build

Signed-off-by: Filip Navara <navara@emclient.com>

* Add back commit cache because of name-rev

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix tests

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix code style

* Fix spelling

* Address PR feedback

Signed-off-by: Filip Navara <navara@emclient.com>

* Update vendor module list

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix getting trees by commit id

Signed-off-by: Filip Navara <navara@emclient.com>

* Fix remaining unit test failures

* Fix GetTreeBySHA

* Avoid running `git name-rev` if not necessary

Signed-off-by: Filip Navara <navara@emclient.com>

* Move Branch code to git module

* Clean up GPG signature verification and fix it for tagged commits

* Address PR feedback (import formatting, copyright headers)

* Make blob lookup by SHA working

* Update tests to use public API

* Allow getting content from any type of object through the blob interface

* Change test to actually expect the object content that is in the GIT repository

* Change one more test to actually expect the object content that is in the GIT repository

* Add comments

1 files changed, 21 insertions, 8 deletions

diff --git a/modules/git/repo_tree.go b/modules/git/repo_tree.go
index 3fa491d529..8a024fe6ac 100644
--- a/modules/git/repo_tree.go
+++ b/modules/git/repo_tree.go
@@ -1,19 +1,23 @@
 // Copyright 2015 The Gogs Authors. All rights reserved.
+// Copyright 2019 The Gitea Authors. All rights reserved.
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
 package git
 
+import (
+	"gopkg.in/src-d/go-git.v4/plumbing"
+)
+
 func (repo *Repository) getTree(id SHA1) (*Tree, error) {
-	treePath := filepathFromSHA1(repo.Path, id.String())
-	if isFile(treePath) {
-		_, err := NewCommand("ls-tree", id.String()).RunInDir(repo.Path)
-		if err != nil {
-			return nil, ErrNotExist{id.String(), ""}
-		}
+	gogitTree, err := repo.gogitRepo.TreeObject(plumbing.Hash(id))
+	if err != nil {
+		return nil, err
 	}
 
-	return NewTree(repo, id), nil
+	tree := NewTree(repo, id)
+	tree.gogitTree = gogitTree
+	return tree, nil
 }
 
 // GetTree find the tree object in the repository.
@@ -31,5 +35,14 @@ func (repo *Repository) GetTree(idStr string) (*Tree, error) {
 	if err != nil {
 		return nil, err
 	}
-	return repo.getTree(id)
+	commitObject, err := repo.gogitRepo.CommitObject(plumbing.Hash(id))
+	if err != nil {
+		return nil, err
+	}
+	treeObject, err := repo.getTree(SHA1(commitObject.TreeHash))
+	if err != nil {
+		return nil, err
+	}
+	treeObject.CommitID = id
+	return treeObject, nil
 }