view tests/test-hgignore.t @ 44118:f81c17ec303c

hgdemandimport: apply lazy module loading to sys.meta_path finders

Python's `sys.meta_path` finders are the primary objects whose job it
is to find a module at import time. When `import` is called, Python
iterates objects in this list and calls `o.find_spec(...)` to find
a `ModuleSpec` (or None if the module couldn't be found by that
finder). If no meta path finder can find a module, import fails.

One of the default meta path finders is `PathFinder`. Its job is to
import modules from the filesystem and is probably the most important
importer. This finder looks at `sys.path` and `sys.path_hooks` to do
its job.

The `ModuleSpec` returned by `MetaPathImporter.find_spec()` has a
`loader` attribute, which defines the concrete module loader to use.
`sys.path_hooks` is a hook point for teaching `PathFinder` to
instantiate custom loader types.

Previously, we injected a custom `sys.path_hook` that told `PathFinder`
to wrap the default loaders with a loader that creates a module object
that is lazy.

This approach worked. But its main limitation was that it only applied
to the `PathFinder` meta path importer. There are other meta path
importers that are registered. And in the case of PyOxidizer loading
modules from memory, `PathFinder` doesn't come into play since
PyOxidizer's own meta path importer was handling all imports.

This commit changes our approach to lazy module loading by proxying
all meta path importers. Specifically, we overload the `find_spec()`
method to swap in a wrapped loader on the `ModuleSpec` before it
is returned. The end result of this is all meta path importers should
be lazy.

As much as I would have loved to utilize .__class__ manipulation to
achieve this, some meta path importers are implemented in C/Rust
in such a way that they cannot be monkeypatched. This is why we
use __getattribute__ to define a proxy.

Also, this change could theoretically open us up to regressions in
meta path importers whose loader is creating module objects which
can't be monkeypatched. But I'm not aware of any of these in the
wild. So I think we'll be safe.

According to hyperfine, this change yields a decent startup time win of
5-6ms:

```
Benchmark #1: ~/.pyenv/versions/3.6.10/bin/python ./hg version
  Time (mean ± σ):      86.8 ms ±   0.5 ms    [User: 78.0 ms, System: 8.7 ms]
  Range (min … max):    86.0 ms …  89.1 ms    50 runs

  Time (mean ± σ):      81.1 ms ±   2.7 ms    [User: 74.5 ms, System: 6.5 ms]
  Range (min … max):    77.8 ms …  90.5 ms    50 runs

Benchmark #2: ~/.pyenv/versions/3.7.6/bin/python ./hg version
  Time (mean ± σ):      78.9 ms ±   0.6 ms    [User: 70.2 ms, System: 8.7 ms]
  Range (min … max):    78.1 ms …  81.2 ms    50 runs

  Time (mean ± σ):      73.4 ms ±   0.6 ms    [User: 65.3 ms, System: 8.0 ms]
  Range (min … max):    72.4 ms …  75.7 ms    50 runs

Benchmark #3: ~/.pyenv/versions/3.8.1/bin/python ./hg version
  Time (mean ± σ):      78.1 ms ±   0.6 ms    [User: 70.2 ms, System: 7.9 ms]
  Range (min … max):    77.4 ms …  80.9 ms    50 runs

  Time (mean ± σ):      72.1 ms ±   0.4 ms    [User: 64.4 ms, System: 7.6 ms]
  Range (min … max):    71.4 ms …  74.1 ms    50 runs
```

Differential Revision: https://phab.mercurial-scm.org/D7954

  $ hg init ignorerepo
  $ cd ignorerepo

debugignore with no hgignore should be deterministic:
  $ hg debugignore
  <nevermatcher>

Issue562: .hgignore requires newline at end:

  $ touch foo
  $ touch bar
  $ touch baz
  $ cat > makeignore.py <<EOF
  > f = open(".hgignore", "w")
  > f.write("ignore\n")
  > f.write("foo\n")
  > # No EOL here
  > f.write("bar")
  > f.close()
  > EOF

  $ "$PYTHON" makeignore.py

Should display baz only:

  $ hg status
  ? baz

  $ rm foo bar baz .hgignore makeignore.py

  $ touch a.o
  $ touch a.c
  $ touch syntax
  $ mkdir dir
  $ touch dir/a.o
  $ touch dir/b.o
  $ touch dir/c.o

  $ hg add dir/a.o
  $ hg commit -m 0
  $ hg add dir/b.o

  $ hg status
  A dir/b.o
  ? a.c
  ? a.o
  ? dir/c.o
  ? syntax

  $ echo "*.o" > .hgignore
  $ hg status
  abort: $TESTTMP/ignorerepo/.hgignore: invalid pattern (relre): *.o (glob)
  [255]

Ensure given files are relative to cwd

  $ echo "dir/.*\.o" > .hgignore
  $ hg status -i
  I dir/c.o

  $ hg debugignore dir/c.o dir/missing.o
  dir/c.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 1: 'dir/.*\.o') (glob)
  dir/missing.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 1: 'dir/.*\.o') (glob)
  $ cd dir
  $ hg debugignore c.o missing.o
  c.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 1: 'dir/.*\.o') (glob)
  missing.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 1: 'dir/.*\.o') (glob)

For icasefs, inexact matches also work, except for missing files

#if icasefs
  $ hg debugignore c.O missing.O
  c.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 1: 'dir/.*\.o') (glob)
  missing.O is not ignored
#endif

  $ cd ..

  $ echo ".*\.o" > .hgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? syntax

Ensure that comments work:

  $ touch 'foo#bar' 'quux#' 'quu0#'
#if no-windows
  $ touch 'baz\' 'baz\wat' 'ba0\#wat' 'ba1\\' 'ba1\\wat' 'quu0\'
#endif

  $ cat <<'EOF' >> .hgignore
  > # full-line comment
  >   # whitespace-only comment line
  > syntax# pattern, no whitespace, then comment
  > a.c  # pattern, then whitespace, then comment
  > baz\\# # (escaped) backslash, then comment
  > ba0\\\#w # (escaped) backslash, escaped comment character, then comment
  > ba1\\\\# # (escaped) backslashes, then comment
  > foo\#b # escaped comment character
  > quux\## escaped comment character at end of name
  > EOF
  $ hg status
  A dir/b.o
  ? .hgignore
  ? quu0#
  ? quu0\ (no-windows !)

  $ cat <<'EOF' > .hgignore
  > .*\.o
  > syntax: glob
  > syntax# pattern, no whitespace, then comment
  > a.c  # pattern, then whitespace, then comment
  > baz\\#* # (escaped) backslash, then comment
  > ba0\\\#w* # (escaped) backslash, escaped comment character, then comment
  > ba1\\\\#* # (escaped) backslashes, then comment
  > foo\#b* # escaped comment character
  > quux\## escaped comment character at end of name
  > quu0[\#]# escaped comment character inside [...]
  > EOF
  $ hg status
  A dir/b.o
  ? .hgignore
  ? ba1\\wat (no-windows !)
  ? baz\wat (no-windows !)
  ? quu0\ (no-windows !)

  $ rm 'foo#bar' 'quux#' 'quu0#'
#if no-windows
  $ rm 'baz\' 'baz\wat' 'ba0\#wat' 'ba1\\' 'ba1\\wat' 'quu0\'
#endif

Check that '^\.' does not ignore the root directory:

  $ echo "^\." > .hgignore
  $ hg status
  A dir/b.o
  ? a.c
  ? a.o
  ? dir/c.o
  ? syntax

Test that patterns from ui.ignore options are read:

  $ echo > .hgignore
  $ cat >> $HGRCPATH << EOF
  > [ui]
  > ignore.other = $TESTTMP/ignorerepo/.hg/testhgignore
  > EOF
  $ echo "glob:**.o" > .hg/testhgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? syntax

empty out testhgignore
  $ echo > .hg/testhgignore

Test relative ignore path (issue4473):

  $ cat >> $HGRCPATH << EOF
  > [ui]
  > ignore.relative = .hg/testhgignorerel
  > EOF
  $ echo "glob:*.o" > .hg/testhgignorerel
  $ cd dir
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? syntax
  $ hg debugignore
  <includematcher includes='.*\\.o(?:/|$)'>

  $ cd ..
  $ echo > .hg/testhgignorerel
  $ echo "syntax: glob" > .hgignore
  $ echo "re:.*\.o" >> .hgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? syntax

  $ echo "syntax: invalid" > .hgignore
  $ hg status
  $TESTTMP/ignorerepo/.hgignore: ignoring invalid syntax 'invalid'
  A dir/b.o
  ? .hgignore
  ? a.c
  ? a.o
  ? dir/c.o
  ? syntax

  $ echo "syntax: glob" > .hgignore
  $ echo "*.o" >> .hgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? syntax

  $ echo "relglob:syntax*" > .hgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? a.o
  ? dir/c.o

  $ echo "relglob:*" > .hgignore
  $ hg status
  A dir/b.o

  $ cd dir
  $ hg status .
  A b.o

  $ hg debugignore
  <includematcher includes='.*(?:/|$)'>

  $ hg debugignore b.o
  b.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 1: '*') (glob)

  $ cd ..

Check patterns that match only the directory

"(fsmonitor !)" below assumes that fsmonitor is enabled with
"walk_on_invalidate = false" (default), which doesn't involve
re-walking whole repository at detection of .hgignore change.

  $ echo "^dir\$" > .hgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? a.o
  ? dir/c.o (fsmonitor !)
  ? syntax

Check recursive glob pattern matches no directories (dir/**/c.o matches dir/c.o)

  $ echo "syntax: glob" > .hgignore
  $ echo "dir/**/c.o" >> .hgignore
  $ touch dir/c.o
  $ mkdir dir/subdir
  $ touch dir/subdir/c.o
  $ hg status
  A dir/b.o
  ? .hgignore
  ? a.c
  ? a.o
  ? syntax
  $ hg debugignore a.c
  a.c is not ignored
  $ hg debugignore dir/c.o
  dir/c.o is ignored
  (ignore rule in $TESTTMP/ignorerepo/.hgignore, line 2: 'dir/**/c.o') (glob)

Check rooted globs

  $ hg purge --all --config extensions.purge=
  $ echo "syntax: rootglob" > .hgignore
  $ echo "a/*.ext" >> .hgignore
  $ for p in a b/a aa; do mkdir -p $p; touch $p/b.ext; done
  $ hg status -A 'set:**.ext'
  ? aa/b.ext
  ? b/a/b.ext
  I a/b.ext

Check using 'include:' in ignore file

  $ hg purge --all --config extensions.purge=
  $ touch foo.included

  $ echo ".*.included" > otherignore
  $ hg status -I "include:otherignore"
  ? foo.included

  $ echo "include:otherignore" >> .hgignore
  $ hg status
  A dir/b.o
  ? .hgignore
  ? otherignore

Check recursive uses of 'include:'

  $ echo "include:nested/ignore" >> otherignore
  $ mkdir nested nested/more
  $ echo "glob:*ignore" > nested/ignore
  $ echo "rootglob:a" >> nested/ignore
  $ touch a nested/a nested/more/a
  $ hg status
  A dir/b.o
  ? nested/a
  ? nested/more/a
  $ rm a nested/a nested/more/a

  $ cp otherignore goodignore
  $ echo "include:badignore" >> otherignore
  $ hg status
  skipping unreadable pattern file 'badignore': $ENOENT$
  A dir/b.o

  $ mv goodignore otherignore

Check using 'include:' while in a non-root directory

  $ cd ..
  $ hg -R ignorerepo status
  A dir/b.o
  $ cd ignorerepo

Check including subincludes

  $ hg revert -q --all
  $ hg purge --all --config extensions.purge=
  $ echo ".hgignore" > .hgignore
  $ mkdir dir1 dir2
  $ touch dir1/file1 dir1/file2 dir2/file1 dir2/file2
  $ echo "subinclude:dir2/.hgignore" >> .hgignore
  $ echo "glob:file*2" > dir2/.hgignore
  $ hg status
  ? dir1/file1
  ? dir1/file2
  ? dir2/file1

Check including subincludes with other patterns

  $ echo "subinclude:dir1/.hgignore" >> .hgignore

  $ mkdir dir1/subdir
  $ touch dir1/subdir/file1
  $ echo "rootglob:f?le1" > dir1/.hgignore
  $ hg status
  ? dir1/file2
  ? dir1/subdir/file1
  ? dir2/file1
  $ rm dir1/subdir/file1

  $ echo "regexp:f.le1" > dir1/.hgignore
  $ hg status
  ? dir1/file2
  ? dir2/file1

Check multiple levels of sub-ignores

  $ touch dir1/subdir/subfile1 dir1/subdir/subfile3 dir1/subdir/subfile4
  $ echo "subinclude:subdir/.hgignore" >> dir1/.hgignore
  $ echo "glob:subfil*3" >> dir1/subdir/.hgignore

  $ hg status
  ? dir1/file2
  ? dir1/subdir/subfile4
  ? dir2/file1

Check include subignore at the same level

  $ mv dir1/subdir/.hgignore dir1/.hgignoretwo
  $ echo "regexp:f.le1" > dir1/.hgignore
  $ echo "subinclude:.hgignoretwo" >> dir1/.hgignore
  $ echo "glob:file*2" > dir1/.hgignoretwo

  $ hg status | grep file2
  [1]
  $ hg debugignore dir1/file2
  dir1/file2 is ignored
  (ignore rule in dir2/.hgignore, line 1: 'file*2')

#if windows

Windows paths are accepted on input

  $ rm dir1/.hgignore
  $ echo "dir1/file*" >> .hgignore
  $ hg debugignore "dir1\file2"
  dir1/file2 is ignored
  (ignore rule in $TESTTMP\ignorerepo\.hgignore, line 4: 'dir1/file*')
  $ hg up -qC .

#endif