encoding: fix trim() to be O(n) instead of O(n^2)
`encoding.trim()` iterated over the possible lengths smaller than the
input and created a slice for each. It then calculated the column
width of the result, which is of course O(n), so the overall algorithm
was O(n). This patch rewrites it to iterate over the unicode
characters, keeping track of the length so far. Also, the old
algorithm started from the end of the string, which made it much worse
when the input is large and the limit is small (such as the typical 72
we pass to it).
You can time it by running something like this:
```
time python3 -c 'from mercurial.utils import stringutil; print(stringutil.ellipsis(b"0123456789" * 1000, 5))'
```
That drops from 4.05 s to 83 ms with this patch (and most of that is
of course startup time).
Differential Revision: https://phab.mercurial-scm.org/D12089
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