procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
test command parsing and dispatch
$ hg init a
$ cd a
Redundant options used to crash (issue436):
$ hg -v log -v
$ hg -v log -v x
$ echo a > a
$ hg ci -Ama
adding a
Missing arg:
$ hg cat
hg cat: invalid arguments
hg cat [OPTION]... FILE...
output the current or given revision of files
options ([+] can be repeated):
-o --output FORMAT print output to file with formatted name
-r --rev REV print the given revision
--decode apply any matching decode filter
-I --include PATTERN [+] include names matching the given patterns
-X --exclude PATTERN [+] exclude names matching the given patterns
-T --template TEMPLATE display with template
(use 'hg cat -h' to show more help)
[10]
Missing parameter for early option:
$ hg log -R 2>&1 | grep 'hg log'
hg log: option -R requires argument
hg log [OPTION]... [FILE]
(use 'hg log -h' to show more help)
"--" may be an option value:
$ hg -R -- log
abort: repository -- not found
[255]
$ hg log -R --
abort: repository -- not found
[255]
$ hg log -T --
-- (no-eol)
$ hg log -T -- -k nomatch
Parsing of early options should stop at "--":
$ hg cat -- --config=hooks.pre-cat=false
--config=hooks.pre-cat=false: no such file in rev cb9a9f314b8b
[1]
$ hg cat -- --debugger
--debugger: no such file in rev cb9a9f314b8b
[1]
Unparsable form of early options:
$ hg cat --debugg
abort: option --debugger may not be abbreviated
[10]
Parsing failure of early options should be detected before executing the
command:
$ hg log -b '--config=hooks.pre-log=false' default
abort: option --config may not be abbreviated
[10]
$ hg log -b -R. default
abort: option -R has to be separated from other options (e.g. not -qR) and --repository may only be abbreviated as --repo
[10]
$ hg log --cwd .. -b --cwd=. default
abort: option --cwd may not be abbreviated
[10]
However, we can't prevent it from loading extensions and configs:
$ cat <<EOF > bad.py
> raise Exception('bad')
> EOF
$ hg log -b '--config=extensions.bad=bad.py' default
*** failed to import extension "bad" from bad.py: bad
abort: option --config may not be abbreviated
[10]
$ mkdir -p badrepo/.hg
$ echo 'invalid-syntax' > badrepo/.hg/hgrc
$ hg log -b -Rbadrepo default
config error at badrepo/.hg/hgrc:1: invalid-syntax
[30]
$ hg log -b --cwd=inexistent default
abort: $ENOENT$: 'inexistent'
[255]
$ hg log -b '--config=ui.traceback=yes' 2>&1 | grep '^Traceback'
Traceback (most recent call last):
$ hg log -b '--config=profiling.enabled=yes' 2>&1 | grep -i sample
Sample count: .*|No samples recorded\. (re)
Early options can't be specified in [aliases] and [defaults] because they are
applied before the command name is resolved:
$ hg log -b '--config=alias.log=log --config=hooks.pre-log=false'
hg log: option -b not recognized
error in definition for alias 'log': --config may only be given on the command
line
[10]
$ hg log -b '--config=defaults.log=--config=hooks.pre-log=false'
abort: option --config may not be abbreviated
[10]
Shell aliases bypass any command parsing rules but for the early one:
$ hg log -b '--config=alias.log=!echo howdy'
howdy
Early options must come first if HGPLAIN=+strictflags is specified:
(BUG: chg cherry-picks early options to pass them as a server command)
#if no-chg
$ HGPLAIN=+strictflags hg log -b --config='hooks.pre-log=false' default
abort: unknown revision '--config=hooks.pre-log=false'
[10]
$ HGPLAIN=+strictflags hg log -b -R. default
abort: unknown revision '-R.'
[10]
$ HGPLAIN=+strictflags hg log -b --cwd=. default
abort: unknown revision '--cwd=.'
[10]
#endif
$ HGPLAIN=+strictflags hg log -b --debugger default
abort: unknown revision '--debugger'
[10]
$ HGPLAIN=+strictflags hg log -b --config='alias.log=!echo pwned' default
abort: unknown revision '--config=alias.log=!echo pwned'
[10]
$ HGPLAIN=+strictflags hg log --config='hooks.pre-log=false' -b default
abort: option --config may not be abbreviated
[10]
$ HGPLAIN=+strictflags hg log -q --cwd=.. -b default
abort: option --cwd may not be abbreviated
[10]
$ HGPLAIN=+strictflags hg log -q -R . -b default
abort: option -R has to be separated from other options (e.g. not -qR) and --repository may only be abbreviated as --repo
[10]
$ HGPLAIN=+strictflags hg --config='hooks.pre-log=false' log -b default
abort: pre-log hook exited with status 1
[40]
$ HGPLAIN=+strictflags hg --cwd .. -q -Ra log -b default
0:cb9a9f314b8b
$ HGPLAIN=+strictflags hg --cwd .. -q --repository a log -b default
0:cb9a9f314b8b
$ HGPLAIN=+strictflags hg --cwd .. -q --repo a log -b default
0:cb9a9f314b8b
For compatibility reasons, HGPLAIN=+strictflags is not enabled by plain HGPLAIN:
$ HGPLAIN= hg log --config='hooks.pre-log=false' -b default
abort: pre-log hook exited with status 1
[40]
$ HGPLAINEXCEPT= hg log --cwd .. -q -Ra -b default
0:cb9a9f314b8b
[defaults]
$ hg cat a
a
$ cat >> $HGRCPATH <<EOF
> [defaults]
> cat = -r null
> EOF
$ hg cat a
a: no such file in rev 000000000000
[1]
$ cd "$TESTTMP"
OSError "No such file or directory" / "The system cannot find the path
specified" should include filename even when it is empty
$ hg -R a archive ''
abort: $ENOENT$: '' (no-windows !)
abort: $ENOTDIR$: '' (windows !)
[255]
#if no-outer-repo
No repo:
$ hg cat
abort: no repository found in '$TESTTMP' (.hg not found)
[10]
#endif
#if rmcwd
Current directory removed:
$ mkdir $TESTTMP/repo1
$ cd $TESTTMP/repo1
$ rm -rf $TESTTMP/repo1
The output could be one of the following and something else:
chg: abort: failed to getcwd (errno = *) (glob)
abort: error getting current working directory: * (glob)
sh: 0: getcwd() failed: $ENOENT$
Since the exact behavior depends on the shell, only check it returns non-zero.
$ HGDEMANDIMPORT=disable hg version -q 2>/dev/null || false
[1]
#endif