Add IO function for creating new directories

[kings177]

Implement a new IO function in the HVM to give Bend the ability to create new directories in the file system.

1. create_directory(path, parents=False, exist_ok=False)

@spec create_directory(str, bool, bool) -> Result[None, Error]

Creates a new directory at the specified path.

Parameters

• path: The path where the new directory should be created
• parents: If True, create parent directories as needed. If False, parent directories must exist
• exist_ok: If True, don't raise an error if the directory already exists

Returns Ok(None) if successful, or Err(reason) if an error occurs.

Possible (but not limited to) errors:

• FileExists: The directory already exists and exist_ok is False
• FileNotFound: A parent directory doesn't exist and parents is False
• PermissionDenied: The user doesn't have permission to create the directory
• OSError: Other OS-level errors (e.g., disk full, invalid path)

Examples

# Create a new directory
result = create_directory("new_folder")
# Ok(None)

# Create a directory with non-existent parents, creating them as needed
result = create_directory("path/to/new/folder", parents=True)
# Ok(None)

# Create a directory, allowing it to exist
result = create_directory("maybe_existing_folder",  exist_ok=True)
# Ok(None)

# Try to create an existing directory
result = create_directory("existing_folder")
# Err(FileExists)

# Create a directory with non-existent parents
result = create_directory("path/to/new/folder")
# Err(FileNotFound)

Considerations

• Implement proper error handling and propagation.
• Ensure thread-safety for directory creation.
• Handle path normalization (e.g., handling '...' and '.' in paths).
• Consider preserving or setting specific permissions for newly created directories.
• Be aware of and handle potential race conditions (e.g., directories being created/deleted concurrently)
• Implement appropriate logging for debugging.

Test cases to implement

1. Create a new directory in an existing parent directory
2. Attempt to create a directory that already exists (with and without exist_ok)
3. Create a directory with multiple levels of non-existent parent directories (with and without parents flag)
4. Attempt to create a directory without proper permissions
5. Create a directory with a very long path name (test path length limits)
6. Create a directory with special characters in the name
7. Attempt to create a directory in a read-only file system
8. Create multiple directories concurrently to test thread-safety
9. Create a directory where a file with the same name already exists
10. Attempt to create a directory with an invalid name (e.g., empty string, only whitespace)
11. Create a directory using relative paths
12. Create a directory using absolute paths
13. Test behavior when disk is full