Issue 1305 in lilypond: GUB compares unexpanded environment PATH with expanded pickle PATH

[lilypond]

Status: Accepted
Owner: ----
Labels: Type-Build Priority-Low

New issue 1305 by percival.music.ca: GUB compares unexpanded environment  
PATH with expanded pickle PATH
http://code.google.com/p/lilypond/issues/detail?id=1305

Starting from a totally clean GUB (no target/ and no downloads/ ), and  
running "make bootstrap" twice, GUB finds a changed environment.

*** environment changed

    #new#  
PATH=/main/src/gub/target/tools/root/usr/bin:~/.usr/bin/:/home/gperciva/aaa/bin/:/home/gperciva/.usr/bin:/home/gperciva/usr/bin:/home/gperciva/.usr/bin:/home/gperciva/.bin:/home/gperciva/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
     
PATH=/main/src/gub/target/tools/root/usr/bin:/home/gperciva/.usr/bin/:/home/gperciva/aaa/bin/:/home/gperciva/.usr/bin:/home/gperciva/usr/bin:/home/gperciva/.usr/bin:/home/gperciva/.bin:/home/gperciva/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games

(yes, this computer's profile is a mess)

The only difference between those two lines is the second one item:  
~/.usr/bin/ vs. /home/gperciva/.usr/bin/

Evidently at some point before writing to target/environment.pickle, GUB  
expands ~ .  But it doesn't do this before comparing os.environ['PATH']  
with the pickle, so in my case it always reports a changed environment.

Granted, I could fix this by changing ~ to $HOME in whatever .profile  
or .bashrc or .profile-my or wherever I'm changing the PATH (probably all  
3), but it would be nice if GUB wasn't confused by this.