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 serve
#if no-outer-repo
no repo
$ hg id
abort: there is no Mercurial repository here (.hg not found)
[255]
#endif
create repo
$ hg init test
$ cd test
$ echo a > a
$ hg ci -Ama
adding a
basic id usage
$ hg id
cb9a9f314b8b tip
$ hg id --debug
cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b tip
$ hg id -q
cb9a9f314b8b
$ hg id -v
cb9a9f314b8b tip
with options
$ hg id -r.
cb9a9f314b8b tip
$ hg id -n
0
$ hg id -t
tip
$ hg id -b
default
$ hg id -i
cb9a9f314b8b
$ hg id -n -t -b -i
cb9a9f314b8b 0 default tip
$ hg id -Tjson
[
{
"bookmarks": [],
"branch": "default",
"dirty": "",
"id": "cb9a9f314b8b",
"node": "ffffffffffffffffffffffffffffffffffffffff",
"parents": [{"node": "cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b", "rev": 0}],
"tags": ["tip"]
}
]
test template keywords and functions which require changectx:
$ hg id -T '{rev} {node|shortest}\n'
2147483647 ffff
$ hg id -T '{parents % "{rev} {node|shortest} {desc}\n"}'
0 cb9a a
$ hg id -T '{parents}\n'
0:cb9a9f314b8b
test nested template: '{tags}'/'{node}' constants shouldn't override the
default keywords, but '{id}' persists because there's no default keyword
for '{id}' (issue5612)
$ hg id -T '{tags}\n'
tip
$ hg id -T '{revset("null:.") % "{rev}:{node|short} {tags} {id}\n"}'
-1:000000000000 cb9a9f314b8b
0:cb9a9f314b8b tip cb9a9f314b8b
with modifications
$ echo b > a
$ hg id -n -t -b -i
cb9a9f314b8b+ 0+ default tip
$ hg id -Tjson
[
{
"bookmarks": [],
"branch": "default",
"dirty": "+",
"id": "cb9a9f314b8b+",
"node": "ffffffffffffffffffffffffffffffffffffffff",
"parents": [{"node": "cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b", "rev": 0}],
"tags": ["tip"]
}
]
other local repo
$ cd ..
$ hg -R test id
cb9a9f314b8b+ tip
#if no-outer-repo
$ hg id test
cb9a9f314b8b+ tip
#endif
with remote http repo
$ cd test
$ hg serve -p $HGPORT1 -d --pid-file=hg.pid
$ cat hg.pid >> $DAEMON_PIDS
$ hg id http://localhost:$HGPORT1/
cb9a9f314b8b
remote with rev number?
$ hg id -n http://localhost:$HGPORT1/
abort: can't query remote revision number, branch, or tags
[255]
remote with tags?
$ hg id -t http://localhost:$HGPORT1/
abort: can't query remote revision number, branch, or tags
[255]
remote with branch?
$ hg id -b http://localhost:$HGPORT1/
abort: can't query remote revision number, branch, or tags
[255]
test bookmark support
$ hg bookmark Y
$ hg bookmark Z
$ hg bookmarks
Y 0:cb9a9f314b8b
* Z 0:cb9a9f314b8b
$ hg id
cb9a9f314b8b+ tip Y/Z
$ hg id --bookmarks
Y Z
test remote identify with bookmarks
$ hg id http://localhost:$HGPORT1/
cb9a9f314b8b Y/Z
$ hg id --bookmarks http://localhost:$HGPORT1/
Y Z
$ hg id -r . http://localhost:$HGPORT1/
cb9a9f314b8b Y/Z
$ hg id --bookmarks -r . http://localhost:$HGPORT1/
Y Z
test invalid lookup
$ hg id -r noNoNO http://localhost:$HGPORT1/
abort: unknown revision 'noNoNO'!
[255]
Make sure we do not obscure unknown requires file entries (issue2649)
$ echo fake >> .hg/requires
$ hg id
abort: repository requires features unknown to this Mercurial: fake!
(see https://mercurial-scm.org/wiki/MissingRequirement for more information)
[255]
$ cd ..
#if no-outer-repo
$ hg id test
abort: repository requires features unknown to this Mercurial: fake!
(see https://mercurial-scm.org/wiki/MissingRequirement for more information)
[255]
#endif