Merge branch 'master' into issue_456

# Conflicts:
#	CHANGELOG.md
#	fs/copy.py

Author: atollk

CHANGELOG.md

@@ -8,11 +8,20 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Unreleased
 
+### Added
+
+- Added `fs.copy.copy_file_if`, `fs.copy.copy_dir_if`, and `fs.copy.copy_fs_if`. 
+  Closes [#458](https://github.com/PyFilesystem/pyfilesystem2/issues/458).
+  
 ### Changed
 
 - FTP servers that do not support the MLST command now try to use the MDTM command to
   retrieve the last modification timestamp of a resource. 
   Closes [#456](https://github.com/PyFilesystem/pyfilesystem2/pull/456).
+  
+### Fixed
+
+- Fixed performance bugs in `fs.copy.copy_dir_if_newer`. Test cases were adapted to catch those bugs in the future.
 
 
 ## [2.4.13] - 2021-03-27

appveyor.yml

@@ -20,10 +20,12 @@ environment:
 
 install:
   # We need wheel installed to build wheels
-  - "%PYTHON%\\python.exe -m pip install pytest pytest-randomly pytest-cov psutil pyftpdlib mock"
+  - "%PYTHON%\\python.exe -m pip install -U pip wheel setuptools"
+  - "%PYTHON%\\python.exe -m pip install pytest"
+  - "%PYTHON%\\python.exe -m pip install -r tests/requirements.txt"
   - "%PYTHON%\\python.exe setup.py install"
 
 build: off
 
 test_script:
-  - "%PYTHON%\\python.exe -m pytest -v tests"
+  - "%PYTHON%\\python.exe -m pytest"