gistfile1.txt

:)owen@dashie:Development$ git init pyc-problem
Initialized empty Git repository in /Users/owen/Development/pyc-problem/.git/

:)owen@dashie:Development$ cd pyc-problem/

:)owen@dashie:pyc-problem (master #)$ echo 'value = "before"' > foo.py

:)owen@dashie:pyc-problem (master #)$ cat > script <<'SCRIPT'
> #!/usr/bin/env python
> 
> import foo
> print foo.value
> SCRIPT

:)owen@dashie:pyc-problem (master #)$ chmod +x script 

:)owen@dashie:pyc-problem (master #)$ ./script 
before

:)owen@dashie:pyc-problem (master #)$ ls
foo.py  foo.pyc script

:)owen@dashie:pyc-problem (master #)$ git add foo.py script

:)owen@dashie:pyc-problem (master #)$ git commit -m 'Original state.'
[master (root-commit) afbf319] Original state.
 2 files changed, 5 insertions(+)
 create mode 100644 foo.py
 create mode 100755 script

:)owen@dashie:pyc-problem (master)$ ls
foo.py  foo.pyc script

:)owen@dashie:pyc-problem (master)$ echo 'value = "after"' > foo.py

:)owen@dashie:pyc-problem (master *)$ git status
# On branch master
# Changes not staged for commit:
#   (use "git add <file>..." to update what will be committed)
#   (use "git checkout -- <file>..." to discard changes in working directory)
#
#	modified:   foo.py
#
# Untracked files:
#   (use "git add <file>..." to include in what will be committed)
#
#	foo.pyc
no changes added to commit (use "git add" and/or "git commit -a")

:)owen@dashie:pyc-problem (master *)$ ./script
after

:)owen@dashie:pyc-problem (master *)$ git add foo.py

:)owen@dashie:pyc-problem (master +)$ git commit -m 'Post-edit state.'
[master 9298eab] Post-edit state.
 1 file changed, 1 insertion(+), 1 deletion(-)

:)owen@dashie:pyc-problem (master)$ git checkout HEAD~
[…detatched HEAD warning…]
HEAD is now at afbf319... Original state.

:)owen@dashie:pyc-problem ((afbf319...))$ ./script
before

:)owen@dashie:pyc-problem ((afbf319...))$ git checkout master
Previous HEAD position was afbf319... Original state.
Switched to branch 'master'

:)owen@dashie:pyc-problem (master)$ ./script
after