view tests/test-merge6.t @ 47315:825d5a5907b4

exewrapper: avoid directly linking against python3X.dll

Subsequent code calls `LoadLibrary()` to attempt to load the DLL, but because of
this symbol reference, there is an attempt to load the DLL used during the build
prior to `_main()` running.  This causes the whole process to fail if the DLL
isn't in the standard search path.  That also means it will never load the DLL
for HackableMercurial.  (Maybe we should get rid of that for py3, since you can
install python for a user without admin rights?)

This could also be resolved by calling `GetProcAddress()` on the symbol and
dereferencing it, but using the environment variable is consistent with the
*.bat file since fc8a5c9ecee0.  (The environment variable persists after the
interpreter is initialized.)

Far more concerning is somehow I've gotten my system into a state where setting
the flag causes any output to the pager to be lost (as if it wasn't set at all)
in MSYS, cmd.exe, WSL, and PowerShell using py3.9.0, but the environment
variable works properly.  I'm sure this flag worked on some versions of py3, so
I'm not sure what's going on here.  This is might be related to init config
related changes in 3.8[1], since it works with 3.7.8, but fails with 3.8.1.
Somebody who understands encoding issues better than I do should give some
thought to if we need to make some changes to our encoding strategy on Windows
with py3.

With or without the flag/envvar, there is proper output if the command is
directly paged by piping to `more.com` (in any environment) or `less` (in MSYS
and WSL), or if paging is disabled with `--pager=no`.  Legacy mode is required
though when Mercurial decides to spin up a pager.

[1] https://bugs.python.org/issue41941

Differential Revision: https://phab.mercurial-scm.org/D10756

  $ cat <<EOF > merge
  > import sys, os
  > print("merging for", os.path.basename(sys.argv[1]))
  > EOF
  $ HGMERGE="$PYTHON ../merge"; export HGMERGE

  $ hg init A1
  $ cd A1
  $ echo This is file foo1 > foo
  $ echo This is file bar1 > bar
  $ hg add foo bar
  $ hg commit -m "commit text"

  $ cd ..
  $ hg clone A1 B1
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd A1
  $ rm bar
  $ hg remove bar
  $ hg commit -m "commit test"

  $ cd ../B1
  $ echo This is file foo22 > foo
  $ hg commit -m "commit test"

  $ cd ..
  $ hg clone A1 A2
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg clone B1 B2
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd A1
  $ hg pull ../B1
  pulling from ../B1
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  new changesets b90e70beeb58
  1 local changesets published
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m "commit test"
bar should remain deleted.
  $ hg manifest --debug
  f9b0e817f6a48de3564c6b2957687c5e7297c5a0 644   foo

  $ cd ../B2
  $ hg pull ../A2
  pulling from ../A2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files (+1 heads)
  new changesets e1adc944e717
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg merge
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m "commit test"
bar should remain deleted.
  $ hg manifest --debug
  f9b0e817f6a48de3564c6b2957687c5e7297c5a0 644   foo

  $ cd ..