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.
this structure seems to tickle a bug in bundle's search for
changesets, so first we have to recreate it
o 8
|
| o 7
| |
| o 6
|/|
o | 5
| |
o | 4
| |
| o 3
| |
| o 2
|/
o 1
|
o 0
$ mkrev()
> {
> revno=$1
> echo "rev $revno"
> echo "rev $revno" > foo.txt
> hg -q ci -m"rev $revno"
> }
setup test repo1
$ hg init repo1
$ cd repo1
$ echo "rev 0" > foo.txt
$ hg ci -Am"rev 0"
adding foo.txt
$ mkrev 1
rev 1
first branch
$ mkrev 2
rev 2
$ mkrev 3
rev 3
back to rev 1 to create second branch
$ hg up -r1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ mkrev 4
rev 4
$ mkrev 5
rev 5
merge first branch to second branch
$ hg up -C -r5
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ HGMERGE=internal:local hg merge
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ echo "merge rev 5, rev 3" > foo.txt
$ hg ci -m"merge first branch to second branch"
one more commit following the merge
$ mkrev 7
rev 7
back to "second branch" to make another head
$ hg up -r5
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ mkrev 8
rev 8
the story so far
$ hg log -G --template "{rev}\n"
@ 8
|
| o 7
| |
| o 6
|/|
o | 5
| |
o | 4
| |
| o 3
| |
| o 2
|/
o 1
|
o 0
check that "hg outgoing" really does the right thing
sanity check of outgoing: expect revs 4 5 6 7 8
$ hg clone -r3 . ../repo2
adding changesets
adding manifests
adding file changes
added 4 changesets with 4 changes to 1 files
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
this should (and does) report 5 outgoing revisions: 4 5 6 7 8
$ hg outgoing --template "{rev}\n" ../repo2
comparing with ../repo2
searching for changes
4
5
6
7
8
test bundle (destination repo): expect 5 revisions
this should bundle the same 5 revisions that outgoing reported, but it
actually bundles 7
$ hg bundle foo.bundle ../repo2
searching for changes
5 changesets found
test bundle (base revision): expect 5 revisions
this should (and does) give exactly the same result as bundle
with a destination repo... i.e. it's wrong too
$ hg bundle --base 3 foo.bundle
5 changesets found
$ cd ..