tests/test-repo-compengines.t

pyoxidizer: produce working Python 3 Windows installers (issue6366)

While we've had code to produce Python 3 Windows installers with
PyOxidizer, we haven't been advertising them on the web site due to
a bug in making TLS connections and issues around resource handling.

This commit upgrades our PyOxidizer install and configuration to
use a recent Git commit of PyOxidizer. This new version of PyOxidizer
contains a *ton* of changes, improvements, and bug fixes. Notably,
Windows shared distributions now mostly "just work" and the TLS bug
and random problems with Python extension modules in the standard
library go away. And Python has been upgraded from 3.7 to 3.8.6.

The price we pay for this upgrade is a ton of backwards incompatible
changes to Starlark.

I applied this commit (the overall series actually) on stable to
produce Windows installers for Mercurial 5.5.2, which I published
shortly before submitting this commit for review.

In order to get the stable branch working, I decided to take a
less aggressive approach to Python resource management. Previously,
we were attempting to load all Python modules from memory and were
performing some hacks to copy Mercurial's non-module resources
into additional directories in Starlark. This commit implements
a resource callback function in Starlark (a new feature since
PyOxidizer 0.7) to dynamically assign standard library resources
to in-memory loading and all other resources to filesystem loading.
This means that Mercurial's files and all the other packages we ship
in the Windows installers (e.g. certifi and pygments) are loaded
from the filesystem instead of from memory. This avoids issues
due to lack of __file__ and enables us to ship a working Python
3 installer on Windows.

The end state of the install layout after this patch is not
ideal for @: we still copy resource files like templates and
help text to directories next to the hg.exe executable. There
is code in @ to use importlib.resources to load these files and
we could likely remove these copies once this lands on @. But for
now, the install layout mimics what we've shipped for seemingly
forever and is backwards compatible. It allows us to achieve the
milestone of working Python 3 Windows installers and gets us a
giant step closer to deleting Python 2.

Differential Revision: https://phab.mercurial-scm.org/D9148

A new repository uses zlib storage, which doesn't need a requirement

  $ hg init default
  $ cd default
  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlogv1
  sparserevlog
  store
  testonly-simplestore (reposimplestore !)

  $ touch foo
  $ hg -q commit -A -m 'initial commit with a lot of repeated repeated repeated text to trigger compression'
  $ hg debugrevlog -c | grep 0x78
      0x78 (x)  :   1 (100.00%)
      0x78 (x)  : 110 (100.00%)

  $ cd ..

Unknown compression engine to format.compression aborts

  $ hg --config format.revlog-compression=unknown init unknown
  abort: compression engines "unknown" defined by format.revlog-compression not available
  (run "hg debuginstall" to list available compression engines)
  [255]

unknown compression engine in a list with known one works fine

  $ hg --config format.revlog-compression=zlib,unknown init zlib-before-unknow
  $ hg --config format.revlog-compression=unknown,zlib init unknown-before-zlib

A requirement specifying an unknown compression engine results in bail

  $ hg init unknownrequirement
  $ cd unknownrequirement
  $ echo exp-compression-unknown >> .hg/requires
  $ hg log
  abort: repository requires features unknown to this Mercurial: exp-compression-unknown!
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]

  $ cd ..

#if zstd

  $ hg --config format.revlog-compression=zstd init zstd
  $ cd zstd
  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlog-compression-zstd
  revlogv1
  sparserevlog
  store
  testonly-simplestore (reposimplestore !)

  $ touch foo
  $ hg -q commit -A -m 'initial commit with a lot of repeated repeated repeated text'

  $ hg debugrevlog -c | grep 0x28
      0x28      :  1 (100.00%)
      0x28      : 98 (100.00%)

  $ cd ..

Specifying a new format.compression on an existing repo won't introduce data
with that engine or a requirement

  $ cd default
  $ touch bar
  $ hg --config format.revlog-compression=zstd -q commit -A -m 'add bar with a lot of repeated repeated repeated text'

  $ cat .hg/requires
  dotencode
  fncache
  generaldelta
  revlogv1
  sparserevlog
  store
  testonly-simplestore (reposimplestore !)

  $ hg debugrevlog -c | grep 0x78
      0x78 (x)  :   2 (100.00%)
      0x78 (x)  : 199 (100.00%)

#endif

checking zlib options
=====================

  $ hg init zlib-level-default
  $ hg init zlib-level-1
  $ cat << EOF >> zlib-level-1/.hg/hgrc
  > [storage]
  > revlog.zlib.level=1
  > EOF
  $ hg init zlib-level-9
  $ cat << EOF >> zlib-level-9/.hg/hgrc
  > [storage]
  > revlog.zlib.level=9
  > EOF


  $ commitone() {
  >    repo=$1
  >    cp $RUNTESTDIR/bundles/issue4438-r1.hg $repo/a
  >    hg -R $repo add $repo/a
  >    hg -R $repo commit -m some-commit
  > }

  $ for repo in zlib-level-default zlib-level-1 zlib-level-9; do
  >     commitone $repo
  > done

  $ $RUNTESTDIR/f -s */.hg/store/data/*
  default/.hg/store/data/foo.i: size=64 (pure !)
  zlib-level-1/.hg/store/data/a.i: size=4146
  zlib-level-9/.hg/store/data/a.i: size=4138
  zlib-level-default/.hg/store/data/a.i: size=4138

Test error cases

  $ hg init zlib-level-invalid
  $ cat << EOF >> zlib-level-invalid/.hg/hgrc
  > [storage]
  > revlog.zlib.level=foobar
  > EOF
  $ commitone zlib-level-invalid
  abort: storage.revlog.zlib.level is not a valid integer ('foobar')
  abort: storage.revlog.zlib.level is not a valid integer ('foobar')
  [255]

  $ hg init zlib-level-out-of-range
  $ cat << EOF >> zlib-level-out-of-range/.hg/hgrc
  > [storage]
  > revlog.zlib.level=42
  > EOF

  $ commitone zlib-level-out-of-range
  abort: invalid value for `storage.revlog.zlib.level` config: 42
  abort: invalid value for `storage.revlog.zlib.level` config: 42
  [255]

#if zstd

checking zstd options
=====================

  $ hg init zstd-level-default --config format.revlog-compression=zstd
  $ hg init zstd-level-1 --config format.revlog-compression=zstd
  $ cat << EOF >> zstd-level-1/.hg/hgrc
  > [storage]
  > revlog.zstd.level=1
  > EOF
  $ hg init zstd-level-22 --config format.revlog-compression=zstd
  $ cat << EOF >> zstd-level-22/.hg/hgrc
  > [storage]
  > revlog.zstd.level=22
  > EOF


  $ commitone() {
  >    repo=$1
  >    cp $RUNTESTDIR/bundles/issue4438-r1.hg $repo/a
  >    hg -R $repo add $repo/a
  >    hg -R $repo commit -m some-commit
  > }

  $ for repo in zstd-level-default zstd-level-1 zstd-level-22; do
  >     commitone $repo
  > done

  $ $RUNTESTDIR/f -s zstd-*/.hg/store/data/*
  zstd-level-1/.hg/store/data/a.i: size=4114
  zstd-level-22/.hg/store/data/a.i: size=4091
  zstd-level-default/\.hg/store/data/a\.i: size=(4094|4102) (re)

Test error cases

  $ hg init zstd-level-invalid --config format.revlog-compression=zstd
  $ cat << EOF >> zstd-level-invalid/.hg/hgrc
  > [storage]
  > revlog.zstd.level=foobar
  > EOF
  $ commitone zstd-level-invalid
  abort: storage.revlog.zstd.level is not a valid integer ('foobar')
  abort: storage.revlog.zstd.level is not a valid integer ('foobar')
  [255]

  $ hg init zstd-level-out-of-range --config format.revlog-compression=zstd
  $ cat << EOF >> zstd-level-out-of-range/.hg/hgrc
  > [storage]
  > revlog.zstd.level=42
  > EOF

  $ commitone zstd-level-out-of-range
  abort: invalid value for `storage.revlog.zstd.level` config: 42
  abort: invalid value for `storage.revlog.zstd.level` config: 42
  [255]

#endif