pathlib2 Library

Common errors

• ModuleNotFoundError: No module named 'pathlib2'

  cause The `pathlib2` package is not installed in the current Python environment or the environment where the code is being executed.
  fix Install the package using pip: `pip install pathlib2` or `pip3 install pathlib2` if you are targeting a specific Python 3 environment.

• TypeError: argument should be a str object or an os.PathLike object returning str, not <class 'pathlib.PosixPath'>

  cause This error often occurs in Python environments (typically Python < 3.4 or 3.5) where `pathlib2` is explicitly used, but a `pathlib.Path` object from the standard library `pathlib` (which might be incidentally installed or available) is passed to a function expecting a `pathlib2.Path` or a string.
  fix Ensure consistent usage of either `pathlib` or `pathlib2`. If targeting older Python versions, always import from `pathlib2` and convert any `pathlib.Path` objects to `pathlib2.Path` or a string if necessary, e.g., `import pathlib2 as pathlib` and explicitly convert objects with `pathlib2.Path(str(some_pathlib_path))`.

• TypeError: unsupported operand type(s) for +: 'PosixPath' and 'str'

  cause This error arises when attempting to concatenate a `pathlib2.Path` object (or `pathlib.Path` from the standard library) directly with a string using the `+` operator, as `Path` objects do not support string concatenation.
  fix Use the `/` operator for path concatenation, which is the idiomatic way to join paths with `pathlib` and `pathlib2`. Alternatively, convert the `Path` object to a string explicitly using `str()` before concatenation if string operations are truly needed. Example: `my_path / 'filename.txt'` or `str(my_path) + '.bak'`.

• AttributeError: 'PosixPath' object has no attribute 'rfind'

  cause This error occurs when a method specific to string objects, like `rfind` (often used with `os.path`), is called on a `pathlib2.Path` object (or `pathlib.Path`). `Path` objects are not strings and have their own set of methods for path manipulation.
  fix Instead of string-based methods, use the object-oriented methods provided by the `pathlib2.Path` object. For example, to get the directory name, use `.parent`; to get the filename, use `.name`. If a string representation is absolutely required for string methods, convert the `Path` object to a string first using `str(my_path).rfind(...)`.

Warnings

• breaking For Python 3.4 and newer, use the standard library module `pathlib` instead of `pathlib2`. `pathlib2` is a backport for older Python versions only.
  Fix: Remove `pathlib2` from your dependencies and change imports from `from pathlib2 import Path` to `from pathlib import Path`.
• gotcha `pathlib2`'s API reflects an older state of the standard library `pathlib`. It does not include features, methods, or bug fixes introduced in `pathlib` in more recent Python versions (e.g., Python 3.5+).
  Fix: If you require newer `pathlib` features, you must migrate to a Python version where the standard library `pathlib` includes those features and switch away from `pathlib2`.
• gotcha The `pathlib2` project is maintained by Jazzband, which implies community maintenance for its intended purpose (older Python versions). Active feature development or significant updates to align with the latest `pathlib` API are not expected.
  Fix: Be aware that `pathlib2` is stable but not actively evolving. For projects needing active development or modern `pathlib` features, prioritize Python versions with a current standard library `pathlib`.

Install

• pip install pathlib2 Install `pathlib2`

Imports

• Path
  wrong:

  from pathlib import Path

  correct:

  from pathlib2 import Path

  When using `pathlib2`, ensure you import `Path` from `pathlib2`, not the standard library's `pathlib`.

Quickstart

This quickstart demonstrates basic usage of `pathlib2.Path` to represent filesystem paths, check existence, manipulate path components, and create/delete files and directories.

from pathlib2 import Path

# Create a Path object
p = Path('/tmp/my_file.txt')

# Check if it exists
print(f"Does {p} exist? {p.exists()}")

# Get parent directory
print(f"Parent directory: {p.parent}")

# Get file name
print(f"File name: {p.name}")

# Create a new path by joining
new_dir = Path('/tmp/my_data')
new_dir.mkdir(exist_ok=True)
new_file = new_dir / 'output.log'
new_file.touch()

print(f"New file created: {new_file.exists()}")
print(f"Contents of new_file: {new_file.read_text()}")

# Clean up
new_file.unlink()
new_dir.rmdir()