I've figured it out. It's not a bug, it's a peculiarity of pprint(). It splits strings to avoid long lines and abuses the fact that in Python strings split with whitespace are concatenated by the parser. Also, in my example newlines are not parsed correctly in the shell. Escaping them, I get the exact same behavior as in subprocess.check_call(): $ python2 print_argv.py $'similarity index 90%\nrename from file1.txt\nrename to file1-mv.txt\nindex 2bef330..f8fd673 100644\n' ['print_argv.py', 'similarity index 90%\nrename from file1.txt\nrename to file1-mv.txt\nindex 2bef330..f8fd673 100644\n'] $ python3 print_argv.py $'similarity index 90%\nrename from file1.txt\nrename to file1-mv.txt\nindex 2bef330..f8fd673 100644\n' ['print_argv.py', 'similarity index 90%\n' 'rename from file1.txt\n' 'rename to file1-mv.txt\n' 'index 2bef330..f8fd673 100644\n']
