Incorrect shutil.copytree() behaviour with symlinks

[vajdaz]

BPO	47049
Nosy	@vajdaz
PRs	bpo-47049: Fix incorrect shutil.copytree() behaviour with symlinks #31967

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2022-03-17.18:50:19.316>
labels = ['type-bug', 'library', '3.11']
title = 'Incorrect shutil.copytree() behaviour with symlinks'
updated_at = <Date 2022-04-04.22:13:23.663>
user = 'https://github.com/vajdaz'

bugs.python.org fields:

activity = <Date 2022-04-04.22:13:23.663>
actor = 'vajdaz'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2022-03-17.18:50:19.316>
creator = 'vajdaz'
dependencies = []
files = []
hgrepos = []
issue_num = 47049
keywords = ['patch']
message_count = 2.0
messages = ['415437', '416700']
nosy_count = 1.0
nosy_names = ['vajdaz']
pr_nums = ['31967']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue47049'
versions = ['Python 3.11']

[vajdaz]

shutil.copytree incorrectly does not copy symlink contents if called
with symlink=False and ignore_dangling_symlinks=True.

The wrong behaviour can be reproduced like this:

$ tree
.
└── a
    ├── a.txt
    └── b
        └── a.txt -> ../a.txt

$ python3 -c "import shutil;shutil.copytree('a/b', 'c', symlinks=False, ignore_dangling_symlinks=True)"

As a result directoy c will be created but it will remain empty.
Expected result is a file c/a.txt with the contents of a/b/a.txt.

[vajdaz]

Because I am a first contributor, the automatic quality checks on GitHub have to be manually started by somebody. How can I reqest this and by whom?

[eakr9014]

This still seems to be an issue even though the underlying PR was closed. Even though ignore_dangling_symlinks is passed to recursive calls of copy_tree now, the function will still incorrectly classify symlinks as dangling even if they aren't because it attempts to do a os.readlink relative to the current working directory, not the copied directory