wireproto: correctly escape batched args and responses (issue4739)
This issue appears to be as old as wireproto batching itself: I can
reproduce the failure as far back as 08ef6b5f3715 trivially by
rebasing the test changes in this patch, which was back in the 1.9
era. I didn't test before that change, because prior to that the
testfile has a different name and I'm lazy.
Note that the test thought it was checking this case, but it actually
wasn't: it put a literal ; in the arg and response for its greet
command, but the mangle/unmangle step defined in the test meant that
instead of "Fo, =;o" going over the wire, "Gp-!><p" went instead,
which doesn't contain any special characters (those being [.=;]) and
thus not exercising the escaping. The test has been updated to use
pre-unmangled special characters, so the request is now "Fo+<:o",
which mangles to "Gp,=;p". I have confirmed that the test fails
without the adjustment to the escaping rules in wireproto.py.
No existing clients of RPC batching were depending on the old behavior
in any way. The only *actual* users of batchable RPCs in core were:
1) largefiles, wherein it batches up many statlfile calls. It sends
hexlified hashes over the wire and gets a 0, 1, or 2 back as a
response. No risk of special characters.
2) setdiscovery, which was using heads() and known(), both of which
communicate via hexlified nodes. Again, no risk of special characters.
Since the escaping functionality has been completely broken since it
was introduced, we know that it has no users. As such, we can change
the escaping mechanism without having to worry about backwards
compatibility issues.
For the curious, this was detected by chance: it happens that the
lz4-compressed text of a test file for remotefilelog compressed to
something containing a ;, which then caused the failure when I moved
remotefilelog to using batching for file content fetching.
initial
$ hg init test-a
$ cd test-a
$ cat >test.txt <<"EOF"
> 1
> 2
> 3
> EOF
$ hg add test.txt
$ hg commit -m "Initial"
clone
$ cd ..
$ hg clone test-a test-b
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
change test-a
$ cd test-a
$ cat >test.txt <<"EOF"
> one
> two
> three
> EOF
$ hg commit -m "Numbers as words"
change test-b
$ cd ../test-b
$ cat >test.txt <<"EOF"
> 1
> 2.5
> 3
> EOF
$ hg commit -m "2 -> 2.5"
now pull and merge from test-a
$ hg pull ../test-a
pulling from ../test-a
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg merge
merging test.txt
warning: conflicts during merge.
merging test.txt incomplete! (edit conflicts, then use 'hg resolve --mark')
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
[1]
resolve conflict
$ cat >test.txt <<"EOF"
> one
> two-point-five
> three
> EOF
$ rm -f *.orig
$ hg resolve -m test.txt
(no more unresolved files)
$ hg commit -m "Merge 1"
change test-a again
$ cd ../test-a
$ cat >test.txt <<"EOF"
> one
> two-point-one
> three
> EOF
$ hg commit -m "two -> two-point-one"
pull and merge from test-a again
$ cd ../test-b
$ hg pull ../test-a
pulling from ../test-a
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg merge --debug
searching for copies back to rev 1
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: 96b70246a118, local: 50c3a7e29886+, remote: 40d11a4173a8
preserving test.txt for resolve of test.txt
test.txt: versions differ -> m
picked tool 'internal:merge' for test.txt (binary False symlink False)
merging test.txt
my test.txt@50c3a7e29886+ other test.txt@40d11a4173a8 ancestor test.txt@96b70246a118
warning: conflicts during merge.
merging test.txt incomplete! (edit conflicts, then use 'hg resolve --mark')
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
[1]
$ cat test.txt
one
<<<<<<< local: 50c3a7e29886 - test: Merge 1
two-point-five
=======
two-point-one
>>>>>>> other: 40d11a4173a8 - test: two -> two-point-one
three
$ hg debugindex test.txt
rev offset length ..... linkrev nodeid p1 p2 (re)
0 0 7 ..... 0 01365c4cca56 000000000000 000000000000 (re)
1 7 9 ..... 1 7b013192566a 01365c4cca56 000000000000 (re)
2 16 15 ..... 2 8fe46a3eb557 01365c4cca56 000000000000 (re)
3 31 2. ..... 3 fc3148072371 7b013192566a 8fe46a3eb557 (re)
4 5. 25 ..... 4 d40249267ae3 8fe46a3eb557 000000000000 (re)
$ hg log
changeset: 4:40d11a4173a8
tag: tip
parent: 2:96b70246a118
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: two -> two-point-one
changeset: 3:50c3a7e29886
parent: 1:d1e159716d41
parent: 2:96b70246a118
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Merge 1
changeset: 2:96b70246a118
parent: 0:b1832b9d912a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Numbers as words
changeset: 1:d1e159716d41
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2 -> 2.5
changeset: 0:b1832b9d912a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial
$ cd ..