posix: always seek to EOF when opening a file in append mode
Python 3 already does this, so skip it there.
Consider the program:
#include <stdio.h>
int main() {
FILE *f = fopen("narf", "w");
fprintf(f, "narf\n");
fclose(f);
f = fopen("narf", "a");
printf("%ld\n", ftell(f));
fprintf(f, "troz\n");
printf("%ld\n", ftell(f));
return 0;
}
on macOS, FreeBSD, and Linux with glibc, this program prints
5
10
but on musl libc (Alpine Linux and probably others) this prints
0
10
By my reading of
https://pubs.opengroup.org/onlinepubs/
009695399/functions/fopen.html
this is technically correct, specifically:
> Opening a file with append mode (a as the first character in the
> mode argument) shall cause all subsequent writes to the file to be
> forced to the then current end-of-file, regardless of intervening
> calls to fseek().
in other words, the file position doesn't really matter in append-mode
files, and we can't depend on it being at all meaningful unless we
perform a seek() before tell() after open(..., 'a'). Experimentally
after a .write() we can do a .tell() and it'll always be reasonable,
but I'm unclear from reading the specification if that's a smart thing
to rely on. This matches what we do on Windows and what Python 3 does
for free, so let's just be consistent. Thanks to Yuya for the idea.
$ hg init
Set up history and working copy
$ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 1
$ hg addremove -q --similarity 0
$ hg commit -m first
$ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 2
$ hg addremove -q --similarity 0
$ hg commit -m second
$ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 wc
$ hg addremove -q --similarity 0
$ hg forget *_*_*-untracked
$ rm *_*_missing-*
Test status
$ hg st -A 'set:modified()'
M content1_content1_content3-tracked
M content1_content2_content1-tracked
M content1_content2_content3-tracked
M missing_content2_content3-tracked
$ hg st -A 'set:added()'
A content1_missing_content1-tracked
A content1_missing_content3-tracked
A missing_missing_content3-tracked
$ hg st -A 'set:removed()'
R content1_content1_content1-untracked
R content1_content1_content3-untracked
R content1_content1_missing-untracked
R content1_content2_content1-untracked
R content1_content2_content2-untracked
R content1_content2_content3-untracked
R content1_content2_missing-untracked
R missing_content2_content2-untracked
R missing_content2_content3-untracked
R missing_content2_missing-untracked
$ hg st -A 'set:deleted()'
! content1_content1_missing-tracked
! content1_content2_missing-tracked
! content1_missing_missing-tracked
! missing_content2_missing-tracked
! missing_missing_missing-tracked
$ hg st -A 'set:missing()'
! content1_content1_missing-tracked
! content1_content2_missing-tracked
! content1_missing_missing-tracked
! missing_content2_missing-tracked
! missing_missing_missing-tracked
$ hg st -A 'set:unknown()'
? content1_missing_content1-untracked
? content1_missing_content3-untracked
? missing_missing_content3-untracked
$ hg st -A 'set:clean()'
C content1_content1_content1-tracked
C content1_content2_content2-tracked
C missing_content2_content2-tracked
Test log
$ hg log -T '{rev}\n' --stat 'set:modified()'
1
content1_content2_content1-tracked | 2 +-
content1_content2_content3-tracked | 2 +-
missing_content2_content3-tracked | 1 +
3 files changed, 3 insertions(+), 2 deletions(-)
0
content1_content1_content3-tracked | 1 +
content1_content2_content1-tracked | 1 +
content1_content2_content3-tracked | 1 +
3 files changed, 3 insertions(+), 0 deletions(-)
Largefiles doesn't crash
$ hg log -T '{rev}\n' --stat 'set:modified()' --config extensions.largefiles=
The fsmonitor extension is incompatible with the largefiles extension and has been disabled. (fsmonitor !)
1
content1_content2_content1-tracked | 2 +-
content1_content2_content3-tracked | 2 +-
missing_content2_content3-tracked | 1 +
3 files changed, 3 insertions(+), 2 deletions(-)
0
content1_content1_content3-tracked | 1 +
content1_content2_content1-tracked | 1 +
content1_content2_content3-tracked | 1 +
3 files changed, 3 insertions(+), 0 deletions(-)
$ hg log -T '{rev}\n' --stat 'set:added()'
1
content1_missing_content1-tracked | 1 -
content1_missing_content3-tracked | 1 -
2 files changed, 0 insertions(+), 2 deletions(-)
0
content1_missing_content1-tracked | 1 +
content1_missing_content3-tracked | 1 +
2 files changed, 2 insertions(+), 0 deletions(-)
$ hg log -T '{rev}\n' --stat 'set:removed()'
1
content1_content2_content1-untracked | 2 +-
content1_content2_content2-untracked | 2 +-
content1_content2_content3-untracked | 2 +-
content1_content2_missing-untracked | 2 +-
missing_content2_content2-untracked | 1 +
missing_content2_content3-untracked | 1 +
missing_content2_missing-untracked | 1 +
7 files changed, 7 insertions(+), 4 deletions(-)
0
content1_content1_content1-untracked | 1 +
content1_content1_content3-untracked | 1 +
content1_content1_missing-untracked | 1 +
content1_content2_content1-untracked | 1 +
content1_content2_content2-untracked | 1 +
content1_content2_content3-untracked | 1 +
content1_content2_missing-untracked | 1 +
7 files changed, 7 insertions(+), 0 deletions(-)
$ hg log -T '{rev}\n' --stat 'set:deleted()'
1
content1_content2_missing-tracked | 2 +-
content1_missing_missing-tracked | 1 -
missing_content2_missing-tracked | 1 +
3 files changed, 2 insertions(+), 2 deletions(-)
0
content1_content1_missing-tracked | 1 +
content1_content2_missing-tracked | 1 +
content1_missing_missing-tracked | 1 +
3 files changed, 3 insertions(+), 0 deletions(-)
$ hg log -T '{rev}\n' --stat 'set:unknown()'
1
content1_missing_content1-untracked | 1 -
content1_missing_content3-untracked | 1 -
2 files changed, 0 insertions(+), 2 deletions(-)
0
content1_missing_content1-untracked | 1 +
content1_missing_content3-untracked | 1 +
2 files changed, 2 insertions(+), 0 deletions(-)
$ hg log -T '{rev}\n' --stat 'set:clean()'
1
content1_content2_content2-tracked | 2 +-
missing_content2_content2-tracked | 1 +
2 files changed, 2 insertions(+), 1 deletions(-)
0
content1_content1_content1-tracked | 1 +
content1_content2_content2-tracked | 1 +
2 files changed, 2 insertions(+), 0 deletions(-)
Test revert
$ hg revert 'set:modified()'
reverting content1_content1_content3-tracked
reverting content1_content2_content1-tracked
reverting content1_content2_content3-tracked
reverting missing_content2_content3-tracked
$ hg revert 'set:added()'
forgetting content1_missing_content1-tracked
forgetting content1_missing_content3-tracked
forgetting missing_missing_content3-tracked
$ hg revert 'set:removed()'
undeleting content1_content1_content1-untracked
undeleting content1_content1_content3-untracked
undeleting content1_content1_missing-untracked
undeleting content1_content2_content1-untracked
undeleting content1_content2_content2-untracked
undeleting content1_content2_content3-untracked
undeleting content1_content2_missing-untracked
undeleting missing_content2_content2-untracked
undeleting missing_content2_content3-untracked
undeleting missing_content2_missing-untracked
$ hg revert 'set:deleted()'
forgetting content1_missing_missing-tracked
forgetting missing_missing_missing-tracked
reverting content1_content1_missing-tracked
reverting content1_content2_missing-tracked
reverting missing_content2_missing-tracked
$ hg revert 'set:unknown()'
$ hg revert 'set:clean()'