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
$ echo "[extensions]" >> $HGRCPATH
$ echo "convert=" >> $HGRCPATH
$ glog()
> {
> hg log -G --template '{rev}:{node|short} "{desc|firstline}"\
> files: {files}\n' "$@"
> }
$ hg init repo1
$ cd repo1
$ echo a > a
$ hg ci -Am adda
adding a
$ echo b > b
$ echo a >> a
$ hg ci -Am addb
adding b
$ PARENTID1=`hg id --debug -i`
$ echo c > c
$ hg ci -Am addc
adding c
$ PARENTID2=`hg id --debug -i`
$ cd ..
$ glog -R repo1
@ 2:e55c719b85b6 "addc" files: c
|
o 1:6d4c2037ddc2 "addb" files: a b
|
o 0:07f494440405 "adda" files: a
$ hg init repo2
$ cd repo2
$ echo b > a
$ echo d > d
$ hg ci -Am addaandd
adding a
adding d
$ INVALIDID1=afd12345af
$ INVALIDID2=28173x36ddd1e67bf7098d541130558ef5534a86
$ CHILDID1=`hg id --debug -i`
$ echo d >> d
$ hg ci -Am changed
$ CHILDID2=`hg id --debug -i`
$ echo e > e
$ hg ci -Am adde
adding e
$ cd ..
$ glog -R repo2
@ 2:a39b65753b0a "adde" files: e
|
o 1:e4ea00df9189 "changed" files: d
|
o 0:527cdedf31fb "addaandd" files: a d
test invalid splicemap1
$ cat > splicemap <<EOF
> $CHILDID2
> EOF
$ hg convert --splicemap splicemap repo2 repo1
abort: syntax error in splicemap(1): child parent1[,parent2] expected
[255]
test invalid splicemap2
$ cat > splicemap <<EOF
> $CHILDID2 $PARENTID1, $PARENTID2, $PARENTID2
> EOF
$ hg convert --splicemap splicemap repo2 repo1
abort: syntax error in splicemap(1): child parent1[,parent2] expected
[255]
test invalid splicemap3
$ cat > splicemap <<EOF
> $INVALIDID1 $INVALIDID2
> EOF
$ hg convert --splicemap splicemap repo2 repo1
abort: splicemap entry afd12345af is not a valid revision identifier
[255]
splice repo2 on repo1
$ cat > splicemap <<EOF
> $CHILDID1 $PARENTID1
> $CHILDID2 $PARENTID2,$CHILDID1
>
> EOF
$ cat splicemap
527cdedf31fbd5ea708aa14eeecf53d4676f38db 6d4c2037ddc2cb2627ac3a244ecce35283268f8e
e4ea00df91897da3079a10fab658c1eddba6617b e55c719b85b60e5102fac26110ba626e7cb6b7dc,527cdedf31fbd5ea708aa14eeecf53d4676f38db
$ hg clone repo1 target1
updating to branch default
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg convert --splicemap splicemap repo2 target1
scanning source...
sorting...
converting...
2 addaandd
spliced in 6d4c2037ddc2cb2627ac3a244ecce35283268f8e as parents of 527cdedf31fbd5ea708aa14eeecf53d4676f38db
1 changed
spliced in e55c719b85b60e5102fac26110ba626e7cb6b7dc and 527cdedf31fbd5ea708aa14eeecf53d4676f38db as parents of e4ea00df91897da3079a10fab658c1eddba6617b
0 adde
$ glog -R target1
o 5:16bc847b02aa "adde" files: e
|
o 4:e30e4fee3418 "changed" files: d
|\
| o 3:e673348c3a3c "addaandd" files: a d
| |
@ | 2:e55c719b85b6 "addc" files: c
|/
o 1:6d4c2037ddc2 "addb" files: a b
|
o 0:07f494440405 "adda" files: a
Test splicemap and conversion order
$ hg init ordered
$ cd ordered
$ echo a > a
$ hg ci -Am adda
adding a
$ hg branch branch
marked working directory as branch branch
(branches are permanent and global, did you want a bookmark?)
$ echo a >> a
$ hg ci -Am changea
$ echo a >> a
$ hg ci -Am changeaagain
$ hg up 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b > b
$ hg ci -Am addb
adding b
We want 2 to depend on 1 and 3. Since 3 is always converted after 2,
the bug should be exhibited with all conversion orders.
$ cat > ../splicemap <<EOF
> `(hg id -r 2 -i --debug)` `(hg id -r 1 -i --debug)`, `(hg id -r 3 -i --debug)`
> EOF
$ cd ..
$ cat splicemap
7c364e7fa7d70ae525610c016317ed717b519d97 717d54d67e6c31fd75ffef2ff3042bdd98418437, 102a90ea7b4a3361e4082ed620918c261189a36a
Test regular conversion
$ hg convert --splicemap splicemap ordered ordered-hg1
initializing destination ordered-hg1 repository
scanning source...
sorting...
converting...
3 adda
2 changea
1 addb
0 changeaagain
spliced in 717d54d67e6c31fd75ffef2ff3042bdd98418437 and 102a90ea7b4a3361e4082ed620918c261189a36a as parents of 7c364e7fa7d70ae525610c016317ed717b519d97
$ glog -R ordered-hg1
o 3:4cb04b9afbf2 "changeaagain" files: a
|\
| o 2:102a90ea7b4a "addb" files: b
| |
o | 1:717d54d67e6c "changea" files: a
|/
o 0:07f494440405 "adda" files: a
Test conversion with parent revisions already in dest, using source
and destination identifiers. Test unknown splicemap target.
$ hg convert -r1 ordered ordered-hg2
initializing destination ordered-hg2 repository
scanning source...
sorting...
converting...
1 adda
0 changea
$ hg convert -r3 ordered ordered-hg2
scanning source...
sorting...
converting...
0 addb
$ cat > splicemap <<EOF
> `(hg -R ordered id -r 2 -i --debug)` \
> `(hg -R ordered-hg2 id -r 1 -i --debug)`,\
> `(hg -R ordered-hg2 id -r 2 -i --debug)`
> deadbeef102a90ea7b4a3361e4082ed620918c26 deadbeef102a90ea7b4a3361e4082ed620918c27
> EOF
$ hg convert --splicemap splicemap ordered ordered-hg2
scanning source...
splice map revision deadbeef102a90ea7b4a3361e4082ed620918c26 is not being converted, ignoring
sorting...
converting...
0 changeaagain
spliced in 717d54d67e6c31fd75ffef2ff3042bdd98418437 and 102a90ea7b4a3361e4082ed620918c261189a36a as parents of 7c364e7fa7d70ae525610c016317ed717b519d97
$ glog -R ordered-hg2
o 3:4cb04b9afbf2 "changeaagain" files: a
|\
| o 2:102a90ea7b4a "addb" files: b
| |
o | 1:717d54d67e6c "changea" files: a
|/
o 0:07f494440405 "adda" files: a
Test empty conversion
$ hg convert --splicemap splicemap ordered ordered-hg2
scanning source...
splice map revision deadbeef102a90ea7b4a3361e4082ed620918c26 is not being converted, ignoring
sorting...
converting...
Test clonebranches
$ hg --config convert.hg.clonebranches=true convert \
> --splicemap splicemap ordered ordered-hg3
initializing destination ordered-hg3 repository
scanning source...
abort: revision 717d54d67e6c31fd75ffef2ff3042bdd98418437 not found in destination repository (lookups with clonebranches=true are not implemented)
[255]
Test invalid dependency
$ cat > splicemap <<EOF
> `(hg -R ordered id -r 2 -i --debug)` \
> deadbeef102a90ea7b4a3361e4082ed620918c26,\
> `(hg -R ordered-hg2 id -r 2 -i --debug)`
> EOF
$ hg convert --splicemap splicemap ordered ordered-hg4
initializing destination ordered-hg4 repository
scanning source...
abort: unknown splice map parent: deadbeef102a90ea7b4a3361e4082ed620918c26
[255]