localrepo: create new function for instantiating a local repo object
Today, there is a single local repository class - localrepository. Its
__init__ is responsible for loading the .hg/requires file and taking
different actions depending on what is present.
In addition, extensions may define a "reposetup" function that
monkeypatches constructed repository instances, often by implementing
a derived type and changing the __class__ of the repo instance.
Work around alternate storage backends and partial clone has made it
clear to me that shoehorning all this logic into __init__ and operating
on an existing instance is too convoluted. For example, localrepository
assumes revlog storage and swapping in non-revlog storage requires
overriding e.g. file() to return something that isn't a revlog. I've
authored various patches that either:
a) teach various methods (like file()) about different states and
taking the appropriate code path at run-time
b) create methods/attributes/callables used for instantiating things
and populating these in __init__
"a" incurs run-time performance penalties and makes code more
complicated since various functions have a bunch of "if storage is X"
branches.
"b" makes localrepository quickly explode in complexity.
My plan for tackling this problem is to make the local repository type
more dynamic. Instead of a static localrepository class/type that
supports all of the local repository configurations (revlogs vs other,
revlogs with ellipsis, revlog v1 versus revlog v2, etc), we'll
dynamically construct a type providing the implementations that are
needed for the repository on disk, derived from the .hg/requires file
and configuration options. The constructed repository type will be
specialized and methods won't need to be taught about different
implementations nor overloaded.
We may also leverage this functionality for building types that don't
implement all attributes. For example, the "intents" feature allows
commands to declare that they are read only. By dynamically
constructing a repository type, we could return a repository instance
with no attributes related to mutating the repository. This could
include things like a "changelog" property implementation that doesn't
check whether it needs to invalidate the hidden revisions set on every
access.
This commit establishes a function for building a local repository
instance. Future commits will start moving functionality from
localrepository.__init__ to this function. Then we'll start dynamically
changing the returned type depending on options that are present.
This change may seem radical. But it should be fully compatible with
the reposetup() model - at least for now.
Differential Revision: https://phab.mercurial-scm.org/D4563
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
(use 'hg cat -h' to show more help)
[255]
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!
[255]
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!
[255]
$ 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!
[255]
$ hg log --cwd .. -b --cwd=. default
abort: option --cwd may not be abbreviated!
[255]
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!
[255]
$ mkdir -p badrepo/.hg
$ echo 'invalid-syntax' > badrepo/.hg/hgrc
$ hg log -b -Rbadrepo default
hg: parse error at badrepo/.hg/hgrc:1: invalid-syntax
[255]
$ 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
[255]
$ hg log -b '--config=defaults.log=--config=hooks.pre-log=false'
abort: option --config may not be abbreviated!
[255]
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'!
[255]
$ HGPLAIN=+strictflags hg log -b -R. default
abort: unknown revision '-R.'!
[255]
$ HGPLAIN=+strictflags hg log -b --cwd=. default
abort: unknown revision '--cwd=.'!
[255]
#endif
$ HGPLAIN=+strictflags hg log -b --debugger default
abort: unknown revision '--debugger'!
[255]
$ HGPLAIN=+strictflags hg log -b --config='alias.log=!echo pwned' default
abort: unknown revision '--config=alias.log=!echo pwned'!
[255]
$ HGPLAIN=+strictflags hg log --config='hooks.pre-log=false' -b default
abort: option --config may not be abbreviated!
[255]
$ HGPLAIN=+strictflags hg log -q --cwd=.. -b default
abort: option --cwd may not be abbreviated!
[255]
$ 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!
[255]
$ HGPLAIN=+strictflags hg --config='hooks.pre-log=false' log -b default
abort: pre-log hook exited with status 1
[255]
$ 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
[255]
$ 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: *: '' (glob)
[255]
#if no-outer-repo
No repo:
$ hg cat
abort: no repository found in '$TESTTMP' (.hg not found)!
[255]
#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