view tests/test-qrecord.t @ 37631:2f626233859b

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

Create configuration

  $ echo "[ui]" >> $HGRCPATH
  $ echo "interactive=true" >> $HGRCPATH

help record (no record)

  $ hg help record
  record extension - commands to interactively select changes for
  commit/qrefresh (DEPRECATED)
  
  The feature provided by this extension has been moved into core Mercurial as
  'hg commit --interactive'.
  
  (use 'hg help extensions' for information on enabling extensions)

help qrecord (no record)

  $ hg help qrecord
  'qrecord' is provided by the following extension:
  
      record        commands to interactively select changes for commit/qrefresh
                    (DEPRECATED)
  
  (use 'hg help extensions' for information on enabling extensions)

  $ echo "[extensions]"     >> $HGRCPATH
  $ echo "record="          >> $HGRCPATH

help record (record)

  $ hg help record
  hg record [OPTION]... [FILE]...
  
  interactively select changes to commit
  
      If a list of files is omitted, all changes reported by 'hg status' will be
      candidates for recording.
  
      See 'hg help dates' for a list of formats valid for -d/--date.
  
      If using the text interface (see 'hg help config'), you will be prompted
      for whether to record changes to each modified file, and for files with
      multiple changes, for each change to use. For each query, the following
      responses are possible:
  
        y - record this change
        n - skip this change
        e - edit this change manually
  
        s - skip remaining changes to this file
        f - record remaining changes to this file
  
        d - done, skip remaining changes and files
        a - record all changes to all remaining files
        q - quit, recording no changes
  
        ? - display help
  
      This command is not available when committing a merge.
  
  (use 'hg help -e record' to show help for the record extension)
  
  options ([+] can be repeated):
  
   -A --addremove           mark new/missing files as added/removed before
                            committing
      --close-branch        mark a branch head as closed
      --amend               amend the parent of the working directory
   -s --secret              use the secret phase for committing
   -e --edit                invoke editor on commit messages
   -I --include PATTERN [+] include names matching the given patterns
   -X --exclude PATTERN [+] exclude names matching the given patterns
   -m --message TEXT        use text as commit message
   -l --logfile FILE        read commit message from file
   -d --date DATE           record the specified date as commit date
   -u --user USER           record the specified user as committer
   -S --subrepos            recurse into subrepositories
   -w --ignore-all-space    ignore white space when comparing lines
   -b --ignore-space-change ignore changes in the amount of white space
   -B --ignore-blank-lines  ignore changes whose lines are all blank
   -Z --ignore-space-at-eol ignore changes in whitespace at EOL
  
  (some details hidden, use --verbose to show complete help)

help (no mq, so no qrecord)

  $ hg help qrecord
  hg qrecord [OPTION]... PATCH [FILE]...
  
  interactively record a new patch
  
      See 'hg help qnew' & 'hg help record' for more information and usage.
  
  (some details hidden, use --verbose to show complete help)

  $ hg init a

qrecord (mq not present)

  $ hg -R a qrecord
  hg qrecord: invalid arguments
  hg qrecord [OPTION]... PATCH [FILE]...
  
  interactively record a new patch
  
  (use 'hg qrecord -h' to show more help)
  [255]

qrecord patch (mq not present)

  $ hg -R a qrecord patch
  abort: 'mq' extension not loaded
  [255]

help (bad mq)

  $ echo "mq=nonexistent" >> $HGRCPATH
  $ hg help qrecord
  *** failed to import extension mq from nonexistent: [Errno *] * (glob)
  hg qrecord [OPTION]... PATCH [FILE]...
  
  interactively record a new patch
  
      See 'hg help qnew' & 'hg help record' for more information and usage.
  
  (some details hidden, use --verbose to show complete help)

help (mq present)

  $ sed 's/mq=nonexistent/mq=/' $HGRCPATH > hgrc.tmp
  $ mv hgrc.tmp $HGRCPATH

  $ hg help qrecord
  hg qrecord [OPTION]... PATCH [FILE]...
  
  interactively record a new patch
  
      See 'hg help qnew' & 'hg help record' for more information and usage.
  
  options ([+] can be repeated):
  
   -e --edit                invoke editor on commit messages
   -g --git                 use git extended diff format
   -U --currentuser         add "From: <current user>" to patch
   -u --user USER           add "From: <USER>" to patch
   -D --currentdate         add "Date: <current date>" to patch
   -d --date DATE           add "Date: <DATE>" to patch
   -I --include PATTERN [+] include names matching the given patterns
   -X --exclude PATTERN [+] exclude names matching the given patterns
   -m --message TEXT        use text as commit message
   -l --logfile FILE        read commit message from file
   -w --ignore-all-space    ignore white space when comparing lines
   -b --ignore-space-change ignore changes in the amount of white space
   -B --ignore-blank-lines  ignore changes whose lines are all blank
   -Z --ignore-space-at-eol ignore changes in whitespace at EOL
      --mq                  operate on patch repository
  
  (some details hidden, use --verbose to show complete help)

  $ cd a

Base commit

  $ cat > 1.txt <<EOF
  > 1
  > 2
  > 3
  > 4
  > 5
  > EOF
  $ cat > 2.txt <<EOF
  > a
  > b
  > c
  > d
  > e
  > f
  > EOF

  $ mkdir dir
  $ cat > dir/a.txt <<EOF
  > hello world
  > 
  > someone
  > up
  > there
  > loves
  > me
  > EOF

  $ hg add 1.txt 2.txt dir/a.txt
  $ hg commit -m 'initial checkin'

Changing files

  $ sed -e 's/2/2 2/;s/4/4 4/' 1.txt > 1.txt.new
  $ sed -e 's/b/b b/' 2.txt > 2.txt.new
  $ sed -e 's/hello world/hello world!/' dir/a.txt > dir/a.txt.new

  $ mv -f 1.txt.new 1.txt
  $ mv -f 2.txt.new 2.txt
  $ mv -f dir/a.txt.new dir/a.txt

Whole diff

  $ hg diff --nodates
  diff -r 1057167b20ef 1.txt
  --- a/1.txt
  +++ b/1.txt
  @@ -1,5 +1,5 @@
   1
  -2
  +2 2
   3
  -4
  +4 4
   5
  diff -r 1057167b20ef 2.txt
  --- a/2.txt
  +++ b/2.txt
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  diff -r 1057167b20ef dir/a.txt
  --- a/dir/a.txt
  +++ b/dir/a.txt
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up

qrecord with bad patch name, should abort before prompting

  $ hg qrecord .hg
  abort: patch name cannot begin with ".hg"
  [255]
  $ hg qrecord ' foo'
  abort: patch name cannot begin or end with whitespace
  [255]
  $ hg qrecord 'foo '
  abort: patch name cannot begin or end with whitespace
  [255]

qrecord a.patch

  $ hg qrecord -d '0 0' -m aaa a.patch <<EOF
  > y
  > y
  > n
  > y
  > y
  > n
  > EOF
  diff --git a/1.txt b/1.txt
  2 hunks, 2 lines changed
  examine changes to '1.txt'? [Ynesfdaq?] y
  
  @@ -1,3 +1,3 @@
   1
  -2
  +2 2
   3
  record change 1/4 to '1.txt'? [Ynesfdaq?] y
  
  @@ -3,3 +3,3 @@
   3
  -4
  +4 4
   5
  record change 2/4 to '1.txt'? [Ynesfdaq?] n
  
  diff --git a/2.txt b/2.txt
  1 hunks, 1 lines changed
  examine changes to '2.txt'? [Ynesfdaq?] y
  
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  record change 3/4 to '2.txt'? [Ynesfdaq?] y
  
  diff --git a/dir/a.txt b/dir/a.txt
  1 hunks, 1 lines changed
  examine changes to 'dir/a.txt'? [Ynesfdaq?] n
  

After qrecord a.patch 'tip'"

  $ hg tip -p
  changeset:   1:5d1ca63427ee
  tag:         a.patch
  tag:         qbase
  tag:         qtip
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     aaa
  
  diff -r 1057167b20ef -r 5d1ca63427ee 1.txt
  --- a/1.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/1.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   1
  -2
  +2 2
   3
   4
   5
  diff -r 1057167b20ef -r 5d1ca63427ee 2.txt
  --- a/2.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/2.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  

After qrecord a.patch 'diff'"

  $ hg diff --nodates
  diff -r 5d1ca63427ee 1.txt
  --- a/1.txt
  +++ b/1.txt
  @@ -1,5 +1,5 @@
   1
   2 2
   3
  -4
  +4 4
   5
  diff -r 5d1ca63427ee dir/a.txt
  --- a/dir/a.txt
  +++ b/dir/a.txt
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up

qrecord b.patch

  $ hg qrecord -d '0 0' -m bbb b.patch <<EOF
  > y
  > y
  > y
  > y
  > EOF
  diff --git a/1.txt b/1.txt
  1 hunks, 1 lines changed
  examine changes to '1.txt'? [Ynesfdaq?] y
  
  @@ -1,5 +1,5 @@
   1
   2 2
   3
  -4
  +4 4
   5
  record change 1/2 to '1.txt'? [Ynesfdaq?] y
  
  diff --git a/dir/a.txt b/dir/a.txt
  1 hunks, 1 lines changed
  examine changes to 'dir/a.txt'? [Ynesfdaq?] y
  
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up
  record change 2/2 to 'dir/a.txt'? [Ynesfdaq?] y
  

After qrecord b.patch 'tip'

  $ hg tip -p
  changeset:   2:b056198bf878
  tag:         b.patch
  tag:         qtip
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     bbb
  
  diff -r 5d1ca63427ee -r b056198bf878 1.txt
  --- a/1.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/1.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   1
   2 2
   3
  -4
  +4 4
   5
  diff -r 5d1ca63427ee -r b056198bf878 dir/a.txt
  --- a/dir/a.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/dir/a.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up
  

After qrecord b.patch 'diff'

  $ hg diff --nodates

  $ cd ..