wireproto: implement batching on peer executor interface
This is a bit more complicated than non-batch requests because we
need to buffer sends until the last request arrives *and* we need
to support resolving futures as data arrives from the remote.
In a classical concurrent.futures executor model, the future
"starts" as soon as it is submitted. However, we have nothing to
start until the last command is submitted.
If we did nothing, calling result() would deadlock, since the future
hasn't "started." So in the case where we queue the command, we return
a special future type whose result() will trigger sendcommands().
This eliminates the deadlock potential. It also serves as a check
against callers who may be calling result() prematurely, as it will
prevent any subsequent callcommands() from working. This behavior
is slightly annoying and a bit restrictive. But it's the world
that half duplex connections forces on us.
In order to support streaming responses, we were previously using
a generator. But with a futures-based API, we're using futures
and not generators. So in order to get streaming, we need a
background thread to read data from the server.
The approach taken in this patch is to leverage the ThreadPoolExecutor
from concurrent.futures for managing a background thread. We create
an executor and future that resolves when all response data is
processed (or an error occurs). When exiting the context manager,
we wait on that background reading before returning.
I was hoping we could manually spin up a threading.Thread and this
would be simple. But I ran into a few deadlocks when implementing.
After looking at the source code to concurrent.futures, I figured
it would just be easier to use a ThreadPoolExecutor than implement
all the code needed to manually manage a thread.
To prove this works, a use of the batch API in discovery has been
updated.
Differential Revision: https://phab.mercurial-scm.org/D3269
$ hg init
$ mkdir d1 d1/d11 d2
$ echo d1/a > d1/a
$ echo d1/ba > d1/ba
$ echo d1/a1 > d1/d11/a1
$ echo d1/b > d1/b
$ echo d2/b > d2/b
$ hg add d1/a d1/b d1/ba d1/d11/a1 d2/b
$ hg commit -m "1"
rename a single file
$ hg rename d1/d11/a1 d2/c
$ hg --config ui.portablefilenames=abort rename d1/a d1/con.xml
abort: filename contains 'con', which is reserved on Windows: d1/con.xml
[255]
$ hg sum
parent: 0:9b4b6e7b2c26 tip
1
branch: default
commit: 1 renamed
update: (current)
phases: 1 draft
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename a single file using absolute paths
$ hg rename `pwd`/d1/d11/a1 `pwd`/d2/c
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename --after a single file
$ mv d1/d11/a1 d2/c
$ hg rename --after d1/d11/a1 d2/c
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename --after a single file when src and tgt already tracked
$ mv d1/d11/a1 d2/c
$ hg addrem -s 0
removing d1/d11/a1
adding d2/c
$ hg rename --after d1/d11/a1 d2/c
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename --after a single file to a nonexistent target filename
$ hg rename --after d1/a dummy
d1/a: not recording move - dummy does not exist
move a single file to an existing directory
$ hg rename d1/d11/a1 d2
$ hg status -C
A d2/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/a1
move --after a single file to an existing directory
$ mv d1/d11/a1 d2
$ hg rename --after d1/d11/a1 d2
$ hg status -C
A d2/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/a1
rename a file using a relative path
$ (cd d1/d11; hg rename ../../d2/b e)
$ hg status -C
A d1/d11/e
d2/b
R d2/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/d11/e
rename --after a file using a relative path
$ (cd d1/d11; mv ../../d2/b e; hg rename --after ../../d2/b e)
$ hg status -C
A d1/d11/e
d2/b
R d2/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/d11/e
rename directory d1 as d3
$ hg rename d1/ d3
moving d1/a to d3/a
moving d1/b to d3/b
moving d1/ba to d3/ba
moving d1/d11/a1 to d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
rename --after directory d1 as d3
$ mv d1 d3
$ hg rename --after d1 d3
moving d1/a to d3/a
moving d1/b to d3/b
moving d1/ba to d3/ba
moving d1/d11/a1 to d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move a directory using a relative path
$ (cd d2; mkdir d3; hg rename ../d1/d11 d3)
moving ../d1/d11/a1 to d3/d11/a1
$ hg status -C
A d2/d3/d11/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d3
move --after a directory using a relative path
$ (cd d2; mkdir d3; mv ../d1/d11 d3; hg rename --after ../d1/d11 d3)
moving ../d1/d11/a1 to d3/d11/a1
$ hg status -C
A d2/d3/d11/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d3
move directory d1/d11 to an existing directory d2 (removes empty d1)
$ hg rename d1/d11/ d2
moving d1/d11/a1 to d2/d11/a1
$ hg status -C
A d2/d11/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d11
move directories d1 and d2 to a new directory d3
$ mkdir d3
$ hg rename d1 d2 d3
moving d1/a to d3/d1/a
moving d1/b to d3/d1/b
moving d1/ba to d3/d1/ba
moving d1/d11/a1 to d3/d1/d11/a1
moving d2/b to d3/d2/b
$ hg status -C
A d3/d1/a
d1/a
A d3/d1/b
d1/b
A d3/d1/ba
d1/ba
A d3/d1/d11/a1
d1/d11/a1
A d3/d2/b
d2/b
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
R d2/b
$ hg update -C
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move --after directories d1 and d2 to a new directory d3
$ mkdir d3
$ mv d1 d2 d3
$ hg rename --after d1 d2 d3
moving d1/a to d3/d1/a
moving d1/b to d3/d1/b
moving d1/ba to d3/d1/ba
moving d1/d11/a1 to d3/d1/d11/a1
moving d2/b to d3/d2/b
$ hg status -C
A d3/d1/a
d1/a
A d3/d1/b
d1/b
A d3/d1/ba
d1/ba
A d3/d1/d11/a1
d1/d11/a1
A d3/d2/b
d2/b
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
R d2/b
$ hg update -C
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move everything under directory d1 to existing directory d2, do not
overwrite existing files (d2/b)
$ hg rename d1/* d2
d2/b: not overwriting - file already committed
(hg rename --force to replace the file by recording a rename)
moving d1/d11/a1 to d2/d11/a1
$ hg status -C
A d2/a
d1/a
A d2/ba
d1/ba
A d2/d11/a1
d1/d11/a1
R d1/a
R d1/ba
R d1/d11/a1
$ diff -u d1/b d2/b
--- d1/b * (glob)
+++ d2/b * (glob)
@@ * (glob)
-d1/b
+d2/b
[1]
$ hg update -C
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/a d2/ba d2/d11/a1
attempt to move one file into a non-existent directory
$ hg rename d1/a dx/
abort: destination dx/ is not a directory
[255]
$ hg status -C
$ hg update -C
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
attempt to move potentially more than one file into a non-existent directory
$ hg rename 'glob:d1/**' dx
abort: with multiple sources, destination must be an existing directory
[255]
move every file under d1 to d2/d21
$ mkdir d2/d21
$ hg rename 'glob:d1/**' d2/d21
moving d1/a to d2/d21/a
moving d1/b to d2/d21/b
moving d1/ba to d2/d21/ba
moving d1/d11/a1 to d2/d21/a1
$ hg status -C
A d2/d21/a
d1/a
A d2/d21/a1
d1/d11/a1
A d2/d21/b
d1/b
A d2/d21/ba
d1/ba
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d21
move --after some files under d1 to d2/d21
$ mkdir d2/d21
$ mv d1/a d1/d11/a1 d2/d21
$ hg rename --after 'glob:d1/**' d2/d21
moving d1/a to d2/d21/a
d1/b: not recording move - d2/d21/b does not exist
d1/ba: not recording move - d2/d21/ba does not exist
moving d1/d11/a1 to d2/d21/a1
$ hg status -C
A d2/d21/a
d1/a
A d2/d21/a1
d1/d11/a1
R d1/a
R d1/d11/a1
$ hg update -C
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d21
move every file under d1 starting with an 'a' to d2/d21 (regexp)
$ mkdir d2/d21
$ hg rename 're:d1/([^a][^/]*/)*a.*' d2/d21
moving d1/a to d2/d21/a
moving d1/d11/a1 to d2/d21/a1
$ hg status -C
A d2/d21/a
d1/a
A d2/d21/a1
d1/d11/a1
R d1/a
R d1/d11/a1
$ hg update -C
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d21
attempt to overwrite an existing file
$ echo "ca" > d1/ca
$ hg rename d1/ba d1/ca
d1/ca: not overwriting - file exists
(hg rename --after to record the rename)
$ hg status -C
? d1/ca
$ hg update -C
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
forced overwrite of an existing file
$ echo "ca" > d1/ca
$ hg rename --force d1/ba d1/ca
$ hg status -C
A d1/ca
d1/ba
R d1/ba
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/ca
attempt to overwrite an existing broken symlink
#if symlink
$ ln -s ba d1/ca
$ hg rename --traceback d1/ba d1/ca
d1/ca: not overwriting - file exists
(hg rename --after to record the rename)
$ hg status -C
? d1/ca
$ hg update -C
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/ca
replace a symlink with a file
$ ln -s ba d1/ca
$ hg rename --force d1/ba d1/ca
$ hg status -C
A d1/ca
d1/ba
R d1/ba
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/ca
#endif
do not copy more than one source file to the same destination file
$ mkdir d3
$ hg rename d1/* d2/* d3
moving d1/d11/a1 to d3/d11/a1
d3/b: not overwriting - d2/b collides with d1/b
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move a whole subtree with "hg rename ."
$ mkdir d3
$ (cd d1; hg rename . ../d3)
moving a to ../d3/d1/a
moving b to ../d3/d1/b
moving ba to ../d3/d1/ba
moving d11/a1 to ../d3/d1/d11/a1
$ hg status -C
A d3/d1/a
d1/a
A d3/d1/b
d1/b
A d3/d1/ba
d1/ba
A d3/d1/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move a whole subtree with "hg rename --after ."
$ mkdir d3
$ mv d1/* d3
$ (cd d1; hg rename --after . ../d3)
moving a to ../d3/a
moving b to ../d3/b
moving ba to ../d3/ba
moving d11/a1 to ../d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move the parent tree with "hg rename .."
$ (cd d1/d11; hg rename .. ../../d3)
moving ../a to ../../d3/a
moving ../b to ../../d3/b
moving ../ba to ../../d3/ba
moving a1 to ../../d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
skip removed files
$ hg remove d1/b
$ hg rename d1 d3
moving d1/a to d3/a
moving d1/ba to d3/ba
moving d1/d11/a1 to d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
transitive rename
$ hg rename d1/b d1/bb
$ hg rename d1/bb d1/bc
$ hg status -C
A d1/bc
d1/b
R d1/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/bc
transitive rename --after
$ hg rename d1/b d1/bb
$ mv d1/bb d1/bc
$ hg rename --after d1/bb d1/bc
$ hg status -C
A d1/bc
d1/b
R d1/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/bc
$ echo "# idempotent renames (d1/b -> d1/bb followed by d1/bb -> d1/b)"
# idempotent renames (d1/b -> d1/bb followed by d1/bb -> d1/b)
$ hg rename d1/b d1/bb
$ echo "some stuff added to d1/bb" >> d1/bb
$ hg rename d1/bb d1/b
$ hg status -C
M d1/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
overwriting with renames (issue1959)
$ hg rename d1/a d1/c
$ hg rename d1/b d1/a
$ hg status -C
M d1/a
d1/b
A d1/c
d1/a
R d1/b
$ hg diff --git
diff --git a/d1/a b/d1/a
--- a/d1/a
+++ b/d1/a
@@ -1,1 +1,1 @@
-d1/a
+d1/b
diff --git a/d1/b b/d1/b
deleted file mode 100644
--- a/d1/b
+++ /dev/null
@@ -1,1 +0,0 @@
-d1/b
diff --git a/d1/a b/d1/c
copy from d1/a
copy to d1/c
$ hg update -C
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/c # The file was marked as added, so 'hg update' action was 'forget'
check illegal path components
$ hg rename d1/d11/a1 .hg/foo
abort: path contains illegal component: .hg/foo
[255]
$ hg status -C
$ hg rename d1/d11/a1 ../foo
abort: ../foo not under root '$TESTTMP'
[255]
$ hg status -C
$ mv d1/d11/a1 .hg/foo
$ hg rename --after d1/d11/a1 .hg/foo
abort: path contains illegal component: .hg/foo
[255]
$ hg status -C
! d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm .hg/foo
$ hg rename d1/d11/a1 .hg
abort: path contains illegal component: .hg/a1
[255]
$ hg --config extensions.largefiles= rename d1/d11/a1 .hg
The fsmonitor extension is incompatible with the largefiles extension and has been disabled. (fsmonitor !)
abort: path contains illegal component: .hg/a1
[255]
$ hg status -C
$ hg rename d1/d11/a1 ..
abort: ../a1 not under root '$TESTTMP'
[255]
$ hg --config extensions.largefiles= rename d1/d11/a1 ..
The fsmonitor extension is incompatible with the largefiles extension and has been disabled. (fsmonitor !)
abort: ../a1 not under root '$TESTTMP'
[255]
$ hg status -C
$ mv d1/d11/a1 .hg
$ hg rename --after d1/d11/a1 .hg
abort: path contains illegal component: .hg/a1
[255]
$ hg status -C
! d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm .hg/a1
$ (cd d1/d11; hg rename ../../d2/b ../../.hg/foo)
abort: path contains illegal component: .hg/foo
[255]
$ hg status -C
$ (cd d1/d11; hg rename ../../d2/b ../../../foo)
abort: ../../../foo not under root '$TESTTMP'
[255]
$ hg status -C
check that stat information such as mtime is preserved on rename - it's unclear
whether the `touch` and `stat` commands are portable, so we mimic them using
python. Not all platforms support precision of even one-second granularity, so
we allow a rather generous fudge factor here; 1234567890 is 2009, and the
primary thing we care about is that it's not the machine's current time;
hopefully it's really unlikely for a machine to have such a broken clock that
this test fails. :)
$ mkdir mtime
Create the file (as empty), then update its mtime and atime to be 1234567890.
>>> import os
>>> filename = "mtime/f"
>>> mtime = 1234567890
>>> open(filename, "w").close()
>>> os.utime(filename, (mtime, mtime))
$ hg ci -qAm 'add mtime dir'
"hg cp" does not preserve the mtime, so it should be newer than the 2009
timestamp.
$ hg cp -q mtime mtime_cp
>>> from __future__ import print_function
>>> import os
>>> filename = "mtime_cp/f"
>>> print(os.stat(filename).st_mtime < 1234567999)
False
"hg mv" preserves the mtime, so it should be ~equal to the 2009 timestamp
(modulo some fudge factor due to not every system supporting 1s-level
precision).
$ hg mv -q mtime mtime_mv
>>> from __future__ import print_function
>>> import os
>>> filename = "mtime_mv/f"
>>> print(os.stat(filename).st_mtime < 1234567999)
True