internals: document CBOR utilization
I spoke with some people at Mozilla about CBOR and they advised me
that we should be careful about the subset of CBOR we use in order
to mitigate security, performance, and compatibility concerns.
This commit establishes a document that attempts to formalize our
use of CBOR.
Its main limitations are on what types are allowed. It explicitly
enumerates which types are supported. Notable missing features
include:
* Indefinite-length arrays and maps
* Text strings (bytes all the way)
* Floats
* Date/time types
* Big integers
* Use of indefinite-length byte strings for map keys, values in
containers.
If we have a need for any of these, we can have a discussion about
them when the time comes.
Differential Revision: https://phab.mercurial-scm.org/D4412
#require svn13
$ svnupanddisplay()
> {
> (
> cd $1;
> svn up -q;
> svn st -v | sed 's/ */ /g' | sort
> limit=''
> if [ $2 -gt 0 ]; then
> limit="--limit=$2"
> fi
> svn log --xml -v $limit | $PYTHON "$TESTDIR/svnxml.py"
> )
> }
$ cat >> $HGRCPATH <<EOF
> [extensions]
> convert =
> EOF
$ hg init a
Add
$ echo a > a/a
$ mkdir -p a/d1/d2
$ echo b > a/d1/d2/b
$ hg --cwd a ci -d '0 0' -A -m 'add a file'
adding a
adding d1/d2/b
Modify
$ svn-safe-append.py a a/a
$ hg --cwd a ci -d '1 0' -m 'modify a file'
$ hg --cwd a tip -q
1:e0e2b8a9156b
$ hg convert -d svn a
assuming destination a-hg
initializing svn repository 'a-hg'
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
1 add a file
0 modify a file
$ svnupanddisplay a-hg-wc 2
2 1 test d1
2 1 test d1/d2
2 1 test d1/d2/b
2 2 test .
2 2 test a
revision: 2
author: test
msg: modify a file
M /a
revision: 1
author: test
msg: add a file
A /a
A /d1
A /d1/d2
A /d1/d2/b
$ ls a a-hg-wc
a:
a
d1
a-hg-wc:
a
d1
$ cmp a/a a-hg-wc/a
Rename
$ hg --cwd a mv a b
$ hg --cwd a ci -d '2 0' -m 'rename a file'
$ hg --cwd a tip -q
2:eb5169441d43
$ hg convert -d svn a
assuming destination a-hg
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 rename a file
$ svnupanddisplay a-hg-wc 1
3 1 test d1
3 1 test d1/d2
3 1 test d1/d2/b
3 3 test .
3 3 test b
revision: 3
author: test
msg: rename a file
D /a
A /b (from /a@2)
$ ls a a-hg-wc
a:
b
d1
a-hg-wc:
b
d1
Copy
$ hg --cwd a cp b c
$ hg --cwd a ci -d '3 0' -m 'copy a file'
$ hg --cwd a tip -q
3:60effef6ab48
$ hg convert -d svn a
assuming destination a-hg
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 copy a file
$ svnupanddisplay a-hg-wc 1
4 1 test d1
4 1 test d1/d2
4 1 test d1/d2/b
4 3 test b
4 4 test .
4 4 test c
revision: 4
author: test
msg: copy a file
A /c (from /b@3)
$ ls a a-hg-wc
a:
b
c
d1
a-hg-wc:
b
c
d1
$ hg --cwd a rm b
Remove
$ hg --cwd a ci -d '4 0' -m 'remove a file'
$ hg --cwd a tip -q
4:87bbe3013fb6
$ hg convert -d svn a
assuming destination a-hg
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 remove a file
$ svnupanddisplay a-hg-wc 1
5 1 test d1
5 1 test d1/d2
5 1 test d1/d2/b
5 4 test c
5 5 test .
revision: 5
author: test
msg: remove a file
D /b
$ ls a a-hg-wc
a:
c
d1
a-hg-wc:
c
d1
Executable
#if execbit
$ chmod +x a/c
#else
$ echo fake >> a/c
#endif
$ hg --cwd a ci -d '5 0' -m 'make a file executable'
#if execbit
$ hg --cwd a tip -q
5:ff42e473c340
#else
$ hg --cwd a tip -q
5:817a700c8cf1
#endif
$ hg convert -d svn a
assuming destination a-hg
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 make a file executable
$ svnupanddisplay a-hg-wc 1
6 1 test d1
6 1 test d1/d2
6 1 test d1/d2/b
6 6 test .
6 6 test c
revision: 6
author: test
msg: make a file executable
M /c
#if execbit
$ test -x a-hg-wc/c
#endif
#if symlink
Symlinks
$ ln -s a/missing a/link
$ hg --cwd a commit -Am 'add symlink'
adding link
$ hg --cwd a mv link newlink
$ hg --cwd a commit -m 'move symlink'
$ hg convert -d svn a a-svnlink
initializing svn repository 'a-svnlink'
initializing svn working copy 'a-svnlink-wc'
scanning source...
sorting...
converting...
7 add a file
6 modify a file
5 rename a file
4 copy a file
3 remove a file
2 make a file executable
1 add symlink
0 move symlink
$ svnupanddisplay a-svnlink-wc 1
8 1 test d1
8 1 test d1/d2
8 1 test d1/d2/b
8 6 test c
8 8 test .
8 8 test newlink
revision: 8
author: test
msg: move symlink
D /link
A /newlink (from /link@7)
Make sure our changes don't affect the rest of the test cases
$ hg --cwd a up 5
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg --cwd a --config extensions.strip= strip -r 6
saved backup bundle to $TESTTMP/a/.hg/strip-backup/bd4f7b7a7067-ed505e42-backup.hg
#endif
Convert with --full adds and removes files that didn't change
$ touch a/f
$ hg -R a ci -Aqmf
$ echo "rename c d" > filemap
$ hg convert -d svn a --filemap filemap --full
assuming destination a-hg
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 f
$ svnupanddisplay a-hg-wc 1
7 7 test .
7 7 test d
7 7 test f
revision: 7
author: test
msg: f
D /c
A /d
D /d1
A /f
$ rm -rf a a-hg a-hg-wc
Executable in new directory
$ hg init a
$ mkdir a/d1
$ echo a > a/d1/a
#if execbit
$ chmod +x a/d1/a
#else
$ echo fake >> a/d1/a
#endif
$ hg --cwd a ci -d '0 0' -A -m 'add executable file in new directory'
adding d1/a
$ hg convert -d svn a
assuming destination a-hg
initializing svn repository 'a-hg'
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 add executable file in new directory
$ svnupanddisplay a-hg-wc 1
1 1 test .
1 1 test d1
1 1 test d1/a
revision: 1
author: test
msg: add executable file in new directory
A /d1
A /d1/a
#if execbit
$ test -x a-hg-wc/d1/a
#endif
Copy to new directory
$ mkdir a/d2
$ hg --cwd a cp d1/a d2/a
$ hg --cwd a ci -d '1 0' -A -m 'copy file to new directory'
$ hg convert -d svn a
assuming destination a-hg
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
0 copy file to new directory
$ svnupanddisplay a-hg-wc 1
2 1 test d1
2 1 test d1/a
2 2 test .
2 2 test d2
2 2 test d2/a
revision: 2
author: test
msg: copy file to new directory
A /d2
A /d2/a (from /d1/a@1)
Branchy history
$ hg init b
$ echo base > b/b
$ hg --cwd b ci -d '0 0' -Ambase
adding b
$ svn-safe-append.py left-1 b/b
$ echo left-1 > b/left-1
$ hg --cwd b ci -d '1 0' -Amleft-1
adding left-1
$ svn-safe-append.py left-2 b/b
$ echo left-2 > b/left-2
$ hg --cwd b ci -d '2 0' -Amleft-2
adding left-2
$ hg --cwd b up 0
1 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ svn-safe-append.py right-1 b/b
$ echo right-1 > b/right-1
$ hg --cwd b ci -d '3 0' -Amright-1
adding right-1
created new head
$ svn-safe-append.py right-2 b/b
$ echo right-2 > b/right-2
$ hg --cwd b ci -d '4 0' -Amright-2
adding right-2
$ hg --cwd b up -C 2
3 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ hg --cwd b merge
merging b
warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
2 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
[1]
$ hg --cwd b revert -r 2 b
$ hg --cwd b resolve -m b
(no more unresolved files)
$ hg --cwd b ci -d '5 0' -m 'merge'
Expect 4 changes
$ hg convert -d svn b
assuming destination b-hg
initializing svn repository 'b-hg'
initializing svn working copy 'b-hg-wc'
scanning source...
sorting...
converting...
5 base
4 left-1
3 left-2
2 right-1
1 right-2
0 merge
$ svnupanddisplay b-hg-wc 0
4 2 test left-1
4 3 test b
4 3 test left-2
4 4 test .
4 4 test right-1
4 4 test right-2
revision: 4
author: test
msg: merge
A /right-1
A /right-2
revision: 3
author: test
msg: left-2
M /b
A /left-2
revision: 2
author: test
msg: left-1
M /b
A /left-1
revision: 1
author: test
msg: base
A /b
Tags are not supported, but must not break conversion
$ rm -rf a a-hg a-hg-wc
$ hg init a
$ echo a > a/a
$ hg --cwd a ci -d '0 0' -A -m 'Add file a'
adding a
$ hg --cwd a tag -d '1 0' -m 'Tagged as v1.0' v1.0
$ hg convert -d svn a
assuming destination a-hg
initializing svn repository 'a-hg'
initializing svn working copy 'a-hg-wc'
scanning source...
sorting...
converting...
1 Add file a
0 Tagged as v1.0
writing Subversion tags is not yet implemented
$ svnupanddisplay a-hg-wc 2
2 1 test a
2 2 test .
2 2 test .hgtags
revision: 2
author: test
msg: Tagged as v1.0
A /.hgtags
revision: 1
author: test
msg: Add file a
A /a
$ rm -rf a a-hg a-hg-wc