##// END OF EJS Templates
posix: always seek to EOF when opening a file in append mode...
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.

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r43163:97ada9b8 5.0.2 stable
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test-worker.t
130 lines | 3.1 KiB | text/troff | Tads3Lexer
Test UI worker interaction
$ cat > t.py <<EOF
> from __future__ import absolute_import, print_function
> import time
> from mercurial import (
> error,
> registrar,
> ui as uimod,
> worker,
> )
> def abort(ui, args):
> if args[0] == 0:
> # by first worker for test stability
> raise error.Abort(b'known exception')
> return runme(ui, [])
> def exc(ui, args):
> if args[0] == 0:
> # by first worker for test stability
> raise Exception('unknown exception')
> return runme(ui, [])
> def runme(ui, args):
> for arg in args:
> ui.status(b'run\n')
> yield 1, arg
> time.sleep(0.1) # easier to trigger killworkers code path
> functable = {
> b'abort': abort,
> b'exc': exc,
> b'runme': runme,
> }
> cmdtable = {}
> command = registrar.command(cmdtable)
> @command(b'test', [], b'hg test [COST] [FUNC]')
> def t(ui, repo, cost=1.0, func=b'runme'):
> cost = float(cost)
> func = functable[func]
> ui.status(b'start\n')
> runs = worker.worker(ui, cost, func, (ui,), range(8))
> for n, i in runs:
> pass
> ui.status(b'done\n')
> EOF
$ abspath=`pwd`/t.py
$ hg init
Run tests with worker enable by forcing a heigh cost
$ hg --config "extensions.t=$abspath" test 100000.0
start
run
run
run
run
run
run
run
run
done
Run tests without worker by forcing a low cost
$ hg --config "extensions.t=$abspath" test 0.0000001
start
run
run
run
run
run
run
run
run
done
#if no-windows
Known exception should be caught, but printed if --traceback is enabled
$ hg --config "extensions.t=$abspath" --config 'worker.numcpus=8' \
> test 100000.0 abort 2>&1
start
abort: known exception
[255]
$ hg --config "extensions.t=$abspath" --config 'worker.numcpus=8' \
> test 100000.0 abort --traceback 2>&1 | egrep '(SystemExit|Abort)'
raise error.Abort(b'known exception')
mercurial.error.Abort: b'known exception' (py3 !)
Abort: known exception (no-py3 !)
SystemExit: 255
Traceback must be printed for unknown exceptions
$ hg --config "extensions.t=$abspath" --config 'worker.numcpus=8' \
> test 100000.0 exc 2>&1 | grep '^Exception'
Exception: unknown exception
Workers should not do cleanups in all cases
$ cat > $TESTTMP/detectcleanup.py <<EOF
> from __future__ import absolute_import
> import atexit
> import os
> import time
> oldfork = os.fork
> count = 0
> parentpid = os.getpid()
> def delayedfork():
> global count
> count += 1
> pid = oldfork()
> # make it easier to test SIGTERM hitting other workers when they have
> # not set up error handling yet.
> if count > 1 and pid == 0:
> time.sleep(0.1)
> return pid
> os.fork = delayedfork
> def cleanup():
> if os.getpid() != parentpid:
> os.write(1, 'should never happen\n')
> atexit.register(cleanup)
> EOF
$ hg --config "extensions.t=$abspath" --config worker.numcpus=8 --config \
> "extensions.d=$TESTTMP/detectcleanup.py" test 100000 abort
start
abort: known exception
[255]
#endif