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# Copyright (C) 2008, 2009 Michael Trier (mtrier@gmail.com) and contributors
#
# This module is part of GitPython and is released under the
# 3-Clause BSD License: https://opensource.org/license/bsd-3-clause/

import gc
import os
import os.path
import sys

import pytest

from test.lib import TestBase
from test.lib.helper import with_rw_directory


class Tutorials(TestBase):
    def tearDown(self):
        gc.collect()

    # ACTUALLY skipped by git.util.rmtree (in local onerror function), from the last
    # call to it via git.objects.submodule.base.Submodule.remove
    # (at "handle separate bare repository"), line 1062.
    #
    # @skipIf(HIDE_WINDOWS_KNOWN_ERRORS,
    #         "FIXME: helper.wrapper fails with: PermissionError: [WinError 5] Access is denied: "
    #         "'C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\test_work_tree_unsupportedryfa60di\\master_repo\\.git\\objects\\pack\\pack-bc9e0787aef9f69e1591ef38ea0a6f566ec66fe3.idx")  # noqa: E501
    @with_rw_directory
    def test_init_repo_object(self, rw_dir):
        # [1-test_init_repo_object]
        from git import Repo

        # rorepo is a Repo instance pointing to the git-python repository.
        # For all you know, the first argument to Repo is a path to the repository you
        # want to work with.
        repo = Repo(self.rorepo.working_tree_dir)
        assert not repo.bare
        # ![1-test_init_repo_object]

        # [2-test_init_repo_object]
        bare_repo = Repo.init(os.path.join(rw_dir, "bare-repo"), bare=True)
        assert bare_repo.bare
        # ![2-test_init_repo_object]

        # [3-test_init_repo_object]
        repo.config_reader()  # Get a config reader for read-only access.
        with repo.config_writer():  # Get a config writer to change configuration.
            pass  # Call release() to be sure changes are written and locks are released.
        # ![3-test_init_repo_object]

        # [4-test_init_repo_object]
        assert not bare_repo.is_dirty()  # Check the dirty state.
        repo.untracked_files  # Retrieve a list of untracked files.
        # ['my_untracked_file']
        # ![4-test_init_repo_object]

        # [5-test_init_repo_object]
        cloned_repo = repo.clone(os.path.join(rw_dir, "to/this/path"))
        assert cloned_repo.__class__ is Repo  # Clone an existing repository.
        assert Repo.init(os.path.join(rw_dir, "path/for/new/repo")).__class__ is Repo
        # ![5-test_init_repo_object]

        # [6-test_init_repo_object]
        with open(os.path.join(rw_dir, "repo.tar"), "wb") as fp:
            repo.archive(fp)
        # ![6-test_init_repo_object]

        # repository paths
        # [7-test_init_repo_object]
        assert os.path.isdir(cloned_repo.working_tree_dir)  # Directory with your work files.
        assert cloned_repo.git_dir.startswith(cloned_repo.working_tree_dir)  # Directory containing the git repository.
        assert bare_repo.working_tree_dir is None  # Bare repositories have no working tree.
        # ![7-test_init_repo_object]

        # heads, tags and references
        # heads are branches in git-speak
        # [8-test_init_repo_object]
        self.assertEqual(
            repo.head.ref,
            repo.heads.master,  # head is a sym-ref pointing to master.
            "It's ok if TC not running from `master`.",
        )
        self.assertEqual(repo.tags["0.3.5"], repo.tag("refs/tags/0.3.5"))  # You can access tags in various ways too.
        self.assertEqual(repo.refs.master, repo.heads["master"])  # .refs provides all refs, i.e. heads...

        if "TRAVIS" not in os.environ:
            self.assertEqual(repo.refs["origin/master"], repo.remotes.origin.refs.master)  # ... remotes ...
        self.assertEqual(repo.refs["0.3.5"], repo.tags["0.3.5"])  # ... and tags.
        # ![8-test_init_repo_object]

        # Create a new head/branch.
        # [9-test_init_repo_object]
        new_branch = cloned_repo.create_head("feature")  # Create a new branch ...
        assert cloned_repo.active_branch != new_branch  # which wasn't checked out yet ...
        self.assertEqual(new_branch.commit, cloned_repo.active_branch.commit)  # pointing to the checked-out commit.
        # It's easy to let a branch point to the previous commit, without affecting anything else.
        # Each reference provides access to the git object it points to, usually commits.
        assert new_branch.set_commit("HEAD~1").commit == cloned_repo.active_branch.commit.parents[0]
        # ![9-test_init_repo_object]

        # Create a new tag reference.
        # [10-test_init_repo_object]
        past = cloned_repo.create_tag(
            "past",
            ref=new_branch,
            message="This is a tag-object pointing to %s" % new_branch.name,
        )
        self.assertEqual(past.commit, new_branch.commit)  # The tag points to the specified commit
        assert past.tag.message.startswith("This is")  # and its object carries the message provided.

        now = cloned_repo.create_tag("now")  # This is a tag-reference. It may not carry meta-data.
        assert now.tag is None
        # ![10-test_init_repo_object]

        # Object handling
        # [11-test_init_repo_object]
        assert now.commit.message != past.commit.message
        # You can read objects directly through binary streams, no working tree required.
        assert (now.commit.tree / "VERSION").data_stream.read().decode("ascii").startswith("3")

        # You can traverse trees as well to handle all contained files of a particular commit.
        file_count = 0
        tree_count = 0
        tree = past.commit.tree
        for item in tree.traverse():
            file_count += item.type == "blob"
            tree_count += item.type == "tree"
        assert file_count and tree_count  # We have accumulated all directories and files.
        self.assertEqual(len(tree.blobs) + len(tree.trees), len(tree))  # A tree is iterable on its children.
        # ![11-test_init_repo_object]

        # Remotes allow handling push, pull and fetch operations.
        # [12-test_init_repo_object]
        from git import RemoteProgress

        class MyProgressPrinter(RemoteProgress):
            def update(self, op_code, cur_count, max_count=None, message=""):
                print(
                    op_code,
                    cur_count,
                    max_count,
                    cur_count / (max_count or 100.0),
                    message or "NO MESSAGE",
                )

        self.assertEqual(len(cloned_repo.remotes), 1)  # We have been cloned, so should be one remote.
        self.assertEqual(len(bare_repo.remotes), 0)  # This one was just initialized.
        origin = bare_repo.create_remote("origin", url=cloned_repo.working_tree_dir)
        assert origin.exists()
        for fetch_info in origin.fetch(progress=MyProgressPrinter()):
            print("Updated %s to %s" % (fetch_info.ref, fetch_info.commit))
        # Create a local branch at the latest fetched master. We specify the name
        # statically, but you have all information to do it programmatically as well.
        bare_master = bare_repo.create_head("master", origin.refs.master)
        bare_repo.head.set_reference(bare_master)
        assert not bare_repo.delete_remote(origin).exists()
        # push and pull behave very similarly.
        # ![12-test_init_repo_object]

        # index
        # [13-test_init_repo_object]
        self.assertEqual(new_branch.checkout(), cloned_repo.active_branch)  # Checking out branch adjusts the wtree.
        self.assertEqual(new_branch.commit, past.commit)  # Now the past is checked out.

        new_file_path = os.path.join(cloned_repo.working_tree_dir, "my-new-file")
        open(new_file_path, "wb").close()  # Create new file in working tree.
        cloned_repo.index.add([new_file_path])  # Add it to the index.
        # Commit the changes to deviate masters history.
        cloned_repo.index.commit("Added a new file in the past - for later merge")

        # Prepare a merge.
        master = cloned_repo.heads.master  # Right-hand side is ahead of us, in the future.
        merge_base = cloned_repo.merge_base(new_branch, master)  # Allows for a three-way merge.
        cloned_repo.index.merge_tree(master, base=merge_base)  # Write the merge result into index.
        cloned_repo.index.commit(
            "Merged past and now into future ;)",
            parent_commits=(new_branch.commit, master.commit),
        )

        # Now new_branch is ahead of master, which probably should be checked out and reset softly.
        # Note that all these operations didn't touch the working tree, as we managed it ourselves.
        # This definitely requires you to know what you are doing! :)
        assert os.path.basename(new_file_path) in new_branch.commit.tree  # New file is now in tree.
        master.commit = new_branch.commit  # Let master point to most recent commit.
        cloned_repo.head.reference = master  # We adjusted just the reference, not the working tree or index.
        # ![13-test_init_repo_object]

        # submodules

        # [14-test_init_repo_object]
        # Create a new submodule and check it out on the spot, setup to track master
        # branch of `bare_repo`. As our GitPython repository has submodules already that
        # point to GitHub, make sure we don't interact with them.
        for sm in cloned_repo.submodules:
            assert not sm.remove().exists()  # after removal, the sm doesn't exist anymore
        sm = cloned_repo.create_submodule("mysubrepo", "path/to/subrepo", url=bare_repo.git_dir, branch="master")

        # .gitmodules was written and added to the index, which is now being committed.
        cloned_repo.index.commit("Added submodule")
        assert sm.exists() and sm.module_exists()  # This submodule is definitely available.
        sm.remove(module=True, configuration=False)  # Remove the working tree.
        assert sm.exists() and not sm.module_exists()  # The submodule itself is still available.

        # Update all submodules, non-recursively to save time. This method is very powerful, go have a look.
        cloned_repo.submodule_update(recursive=False)
        assert sm.module_exists()  # The submodule's working tree was checked out by update.
        # ![14-test_init_repo_object]

    @with_rw_directory
    def test_references_and_objects(self, rw_dir):
        # [1-test_references_and_objects]
        import git

        repo = git.Repo.clone_from(self._small_repo_url(), os.path.join(rw_dir, "repo"), branch="master")

        heads = repo.heads
        master = heads.master  # Lists can be accessed by name for convenience.
        master.commit  # the commit pointed to by head called master.
        master.rename("new_name")  # Rename heads.
        master.rename("master")
        # ![1-test_references_and_objects]

        # [2-test_references_and_objects]
        tags = repo.tags
        tagref = tags[0]
        tagref.tag  # Tags may have tag objects carrying additional information
        tagref.commit  # but they always point to commits.
        repo.delete_tag(tagref)  # Delete or
        repo.create_tag("my_tag")  # create tags using the repo for convenience.
        # ![2-test_references_and_objects]

        # [3-test_references_and_objects]
        head = repo.head  # The head points to the active branch/ref.
        master = head.reference  # Retrieve the reference the head points to.
        master.commit  # From here you use it as any other reference.
        # ![3-test_references_and_objects]
        #
        # [4-test_references_and_objects]
        log = master.log()
        log[0]  # first (i.e. oldest) reflog entry
        log[-1]  # last (i.e. most recent) reflog entry
        # ![4-test_references_and_objects]

        # [5-test_references_and_objects]
        new_branch = repo.create_head("new")  # Create a new one.
        new_branch.commit = "HEAD~10"  # Set branch to another commit without changing index or working trees.
        repo.delete_head(new_branch)  # Delete an existing head - only works if it is not checked out.
        # ![5-test_references_and_objects]

        # [6-test_references_and_objects]
        new_tag = repo.create_tag("my_new_tag", message="my message")
        # You cannot change the commit a tag points to. Tags need to be re-created.
        self.assertRaises(AttributeError, setattr, new_tag, "commit", repo.commit("HEAD~1"))
        repo.delete_tag(new_tag)
        # ![6-test_references_and_objects]

        # [7-test_references_and_objects]
        new_branch = repo.create_head("another-branch")
        repo.head.reference = new_branch
        # ![7-test_references_and_objects]

        # [8-test_references_and_objects]
        hc = repo.head.commit
        hct = hc.tree
        assert hc != hct
        assert hc != repo.tags[0]
        assert hc == repo.head.reference.commit
        # ![8-test_references_and_objects]

        # [9-test_references_and_objects]
        self.assertEqual(hct.type, "tree")  # Preset string type, being a class attribute.
        assert hct.size > 0  # size in bytes
        assert len(hct.hexsha) == 40
        assert len(hct.binsha) == 20
        # ![9-test_references_and_objects]

        # [10-test_references_and_objects]
        self.assertEqual(hct.path, "")  # Root tree has no path.
        assert hct.trees[0].path != ""  # The first contained item has one though.
        self.assertEqual(hct.mode, 0o40000)  # Trees have the mode of a Linux directory.
        self.assertEqual(hct.blobs[0].mode, 0o100644)  # Blobs have specific mode, comparable to a standard Linux fs.
        # ![10-test_references_and_objects]

        # [11-test_references_and_objects]
        hct.blobs[0].data_stream.read()  # Stream object to read data from.
        hct.blobs[0].stream_data(open(os.path.join(rw_dir, "blob_data"), "wb"))  # Write data to a given stream.
        # ![11-test_references_and_objects]

        # [12-test_references_and_objects]
        repo.commit("master")
        repo.commit("v0.8.1")
        repo.commit("HEAD~10")
        # ![12-test_references_and_objects]

        # [13-test_references_and_objects]
        fifty_first_commits = list(repo.iter_commits("master", max_count=50))
        assert len(fifty_first_commits) == 50
        # This will return commits 21-30 from the commit list as traversed backwards master.
        ten_commits_past_twenty = list(repo.iter_commits("master", max_count=10, skip=20))
        assert len(ten_commits_past_twenty) == 10
        assert fifty_first_commits[20:30] == ten_commits_past_twenty
        # ![13-test_references_and_objects]

        # [14-test_references_and_objects]
        headcommit = repo.head.commit
        assert len(headcommit.hexsha) == 40
        assert len(headcommit.parents) > 0
        assert headcommit.tree.type == "tree"
        assert len(headcommit.author.name) != 0
        assert isinstance(headcommit.authored_date, int)
        assert len(headcommit.committer.name) != 0
        assert isinstance(headcommit.committed_date, int)
        assert headcommit.message != ""
        # ![14-test_references_and_objects]

        # [15-test_references_and_objects]
        import time

        time.asctime(time.gmtime(headcommit.committed_date))
        time.strftime("%a, %d %b %Y %H:%M", time.gmtime(headcommit.committed_date))
        # ![15-test_references_and_objects]

        # [16-test_references_and_objects]
        assert headcommit.parents[0].parents[0].parents[0] == repo.commit("master^^^")
        # ![16-test_references_and_objects]

        # [17-test_references_and_objects]
        tree = repo.heads.master.commit.tree
        assert len(tree.hexsha) == 40
        # ![17-test_references_and_objects]

        # [18-test_references_and_objects]
        assert len(tree.trees) > 0  # Trees are subdirectories.
        assert len(tree.blobs) > 0  # Blobs are files.
        assert len(tree.blobs) + len(tree.trees) == len(tree)
        # ![18-test_references_and_objects]

        # [19-test_references_and_objects]
        self.assertEqual(tree["smmap"], tree / "smmap")  # Access by index and by sub-path.
        for entry in tree:  # Intuitive iteration of tree members.
            print(entry)
        blob = tree.trees[1].blobs[0]  # Let's get a blob in a sub-tree.
        assert blob.name
        assert len(blob.path) < len(blob.abspath)
        self.assertEqual(tree.trees[1].name + "/" + blob.name, blob.path)  # This is how relative blob path generated.
        self.assertEqual(tree[blob.path], blob)  # You can use paths like 'dir/file' in tree,
        # ![19-test_references_and_objects]

        # [20-test_references_and_objects]
        assert tree / "smmap" == tree["smmap"]
        assert tree / blob.path == tree[blob.path]
        # ![20-test_references_and_objects]

        # [21-test_references_and_objects]
        # This example shows the various types of allowed ref-specs.
        assert repo.tree() == repo.head.commit.tree
        past = repo.commit("HEAD~5")
        assert repo.tree(past) == repo.tree(past.hexsha)
        self.assertEqual(repo.tree("v0.8.1").type, "tree")  # Yes, you can provide any refspec - works everywhere.
        # ![21-test_references_and_objects]

        # [22-test_references_and_objects]
        assert len(tree) < len(list(tree.traverse()))
        # ![22-test_references_and_objects]

        # [23-test_references_and_objects]
        index = repo.index
        # The index contains all blobs in a flat list.
        assert len(list(index.iter_blobs())) == len([o for o in repo.head.commit.tree.traverse() if o.type == "blob"])
        # Access blob objects.
        for (_path, _stage), _entry in index.entries.items():
            pass
        new_file_path = os.path.join(repo.working_tree_dir, "new-file-name")
        open(new_file_path, "w").close()
        index.add([new_file_path])  # Add a new file to the index.
        index.remove(["LICENSE"])  # Remove an existing one.
        assert os.path.isfile(os.path.join(repo.working_tree_dir, "LICENSE"))  # Working tree is untouched.

        self.assertEqual(index.commit("my commit message").type, "commit")  # Commit changed index.
        repo.active_branch.commit = repo.commit("HEAD~1")  # Forget last commit.

        from git import Actor

        author = Actor("An author", "author@example.com")
        committer = Actor("A committer", "committer@example.com")
        # Commit with a commit message, author, and committer.
        index.commit("my commit message", author=author, committer=committer)
        # ![23-test_references_and_objects]

        # [24-test_references_and_objects]
        from git import IndexFile

        # Load a tree into a temporary index, which exists just in memory.
        IndexFile.from_tree(repo, "HEAD~1")
        # Merge two trees three-way into memory...
        merge_index = IndexFile.from_tree(repo, "HEAD~10", "HEAD", repo.merge_base("HEAD~10", "HEAD"))
        # ...and persist it.
        merge_index.write(os.path.join(rw_dir, "merged_index"))
        # ![24-test_references_and_objects]

        # [25-test_references_and_objects]
        empty_repo = git.Repo.init(os.path.join(rw_dir, "empty"))
        origin = empty_repo.create_remote("origin", repo.remotes.origin.url)
        assert origin.exists()
        assert origin == empty_repo.remotes.origin == empty_repo.remotes["origin"]
        origin.fetch()  # Ensure we actually have data. fetch() returns useful information.
        # Set up a local tracking branch of a remote branch.
        empty_repo.create_head("master", origin.refs.master)  # Create local branch "master" from remote "master".
        empty_repo.heads.master.set_tracking_branch(origin.refs.master)  # Set local "master" to track remote "master.
        empty_repo.heads.master.checkout()  # Check out local "master" to working tree.
        # Three above commands in one:
        empty_repo.create_head("master", origin.refs.master).set_tracking_branch(origin.refs.master).checkout()
        # Rename remotes.
        origin.rename("new_origin")
        # Push and pull behaves similarly to `git push|pull`.
        origin.pull()
        origin.push()  # Attempt push, ignore errors.
        origin.push().raise_if_error()  # Push and raise error if it fails.
        # assert not empty_repo.delete_remote(origin).exists()     # Create and delete remotes.
        # ![25-test_references_and_objects]

        # [26-test_references_and_objects]
        assert origin.url == repo.remotes.origin.url
        with origin.config_writer as cw:
            cw.set("pushurl", "other_url")

        # Please note that in Python 2, writing origin.config_writer.set(...) is totally
        # safe. In py3 __del__ calls can be delayed, thus not writing changes in time.
        # ![26-test_references_and_objects]

        # [27-test_references_and_objects]
        hcommit = repo.head.commit
        hcommit.diff()  # diff tree against index.
        hcommit.diff("HEAD~1")  # diff tree against previous tree.
        hcommit.diff(None)  # diff tree against working tree.

        index = repo.index
        index.diff()  # diff index against itself yielding empty diff.
        index.diff(None)  # diff index against working copy.
        index.diff("HEAD")  # diff index against current HEAD tree.
        # ![27-test_references_and_objects]

        # [28-test_references_and_objects]
        # Traverse added Diff objects only
        for diff_added in hcommit.diff("HEAD~1").iter_change_type("A"):
            print(diff_added)
        # ![28-test_references_and_objects]

        # [29-test_references_and_objects]
        # Reset our working tree 10 commits into the past.
        past_branch = repo.create_head("past_branch", "HEAD~10")
        repo.head.reference = past_branch
        assert not repo.head.is_detached
        # Reset the index and working tree to match the pointed-to commit.
        repo.head.reset(index=True, working_tree=True)

        # To detach your head, you have to point to a commit directly.
        repo.head.reference = repo.commit("HEAD~5")
        assert repo.head.is_detached
        # Now our head points 15 commits into the past, whereas the working tree
        # and index are 10 commits in the past.
        # ![29-test_references_and_objects]

        # [30-test_references_and_objects]
        # Check out the branch using git-checkout.
        # It will fail as the working tree appears dirty.
        self.assertRaises(git.GitCommandError, repo.heads.master.checkout)
        repo.heads.past_branch.checkout()
        # ![30-test_references_and_objects]

        # [31-test_references_and_objects]
        git = repo.git
        git.checkout("HEAD", b="my_new_branch")  # Create a new branch.
        git.branch("another-new-one")
        git.branch("-D", "another-new-one")  # Pass strings for full control over argument order.
        git.for_each_ref()  # '-' becomes '_' when calling it.
        # ![31-test_references_and_objects]

        repo.git.clear_cache()

    @pytest.mark.xfail(
        sys.platform == "cygwin",
        reason="Cygwin GitPython can't find SHA for submodule",
        raises=ValueError,
    )
    def test_submodules(self):
        # [1-test_submodules]
        repo = self.rorepo
        sms = repo.submodules

        assert len(sms) == 1
        sm = sms[0]
        self.assertEqual(sm.name, "gitdb")  # GitPython has gitdb as its one and only (direct) submodule...
        self.assertEqual(sm.children()[0].name, "smmap")  # ...which has smmap as its one and only submodule.

        # The module is the repository referenced by the submodule.
        assert sm.module_exists()  # The module is available, which doesn't have to be the case.
        assert sm.module().working_tree_dir.endswith("gitdb")
        # The submodule's absolute path is the module's path.
        assert sm.abspath == sm.module().working_tree_dir
        self.assertEqual(len(sm.hexsha), 40)  # Its sha defines the commit to check out.
        assert sm.exists()  # Yes, this submodule is valid and exists.
        # Read its configuration conveniently.
        assert sm.config_reader().get_value("path") == sm.path
        self.assertEqual(len(sm.children()), 1)  # Query the submodule hierarchy.
        # ![1-test_submodules]

    @with_rw_directory
    def test_add_file_and_commit(self, rw_dir):
        import git

        repo_dir = os.path.join(rw_dir, "my-new-repo")
        file_name = os.path.join(repo_dir, "new-file")

        r = git.Repo.init(repo_dir)
        # This function just creates an empty file.
        open(file_name, "wb").close()
        r.index.add([file_name])
        r.index.commit("initial commit")

        # ![test_add_file_and_commit]