view tests/test-eol.t @ 20742:3681de20b0a7

parsers: fail fast if Python has wrong minor version (issue4110)

This change causes an informative ImportError to be raised when importing
the parsers extension module if the minor version of the currently-running
Python interpreter doesn't match that of the Python used when compiling
the extension module.

This change also exposes a parsers.versionerrortext constant in the
C implementation of the module.  Its presence can be used to determine
whether this behavior is present in a version of the module.  The value
of the constant is the leading text of the ImportError raised and is set
to "Python minor version mismatch".

Here is an example of what the new error looks like:

  Traceback (most recent call last):
    File "test.py", line 1, in <module>
      import mercurial.parsers
  ImportError: Python minor version mismatch: The Mercurial extension
  modules were compiled with Python 2.7.6, but Mercurial is currently using
  Python with sys.hexversion=33883888: Python 2.5.6
  (r256:88840, Nov 18 2012, 05:37:10)
  [GCC 4.2.1 Compatible Apple Clang 4.1 ((tags/Apple/clang-421.11.66))]
   at: /opt/local/Library/Frameworks/Python.framework/Versions/2.5/Resources/
    Python.app/Contents/MacOS/Python

The reason for raising an error in this scenario is that Python's C API
is known not to be compatible from minor version to minor version, even
if sys.api_version is the same.  See for example this Python bug report
about incompatibilities between 2.5 and 2.6+:

  http://bugs.python.org/issue8118

These incompatibilities can cause Mercurial to break in mysterious,
unforeseen ways.  For example, when Mercurial compiled with Python 2.7 was
run with 2.5, the following crash occurred when running "hg status":

  http://bz.selenic.com/show_bug.cgi?id=4110

After this crash was fixed, running with Python 2.5 no longer crashes, but
the following puzzling behavior still occurs:

    $ hg status
      ...
      File ".../mercurial/changelog.py", line 123, in __init__
        revlog.revlog.__init__(self, opener, "00changelog.i")
      File ".../mercurial/revlog.py", line 251, in __init__
        d = self._io.parseindex(i, self._inline)
      File ".../mercurial/revlog.py", line 158, in parseindex
        index, cache = parsers.parse_index2(data, inline)
    TypeError: data is not a string

which can be reproduced more simply with:

    import mercurial.parsers as parsers
    parsers.parse_index2("", True)

Both the crash and the TypeError occurred because the Python C API's
PyString_Check() returns the wrong value when the C header files from
Python 2.7 are run with Python 2.5.  This is an example of an
incompatibility of the sort mentioned in the Python bug report above.

Failing fast with an informative error message results in a better user
experience in cases like the above.  The information in the ImportError
also simplifies troubleshooting for those on Mercurial mailing lists, the
bug tracker, etc.

This patch only adds the version check to parsers.c, which is sufficient
to affect command-line commands like "hg status" and "hg summary".
An idea for a future improvement is to move the version-checking C code
to a more central location, and have it run when importing all
Mercurial extension modules and not just parsers.c.

Test EOL extension

  $ cat >> $HGRCPATH <<EOF
  > [diff]
  > git = True
  > EOF

Set up helpers

  $ cat > switch-eol.py <<EOF
  > import sys
  > try:
  >     import os, msvcrt
  >     msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
  >     msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
  > except ImportError:
  >     pass
  > (old, new) = sys.argv[1] == 'LF' and ('\n', '\r\n') or ('\r\n', '\n')
  > print "%% switching encoding from %r to %r" % (old, new)
  > for path in sys.argv[2:]:
  >     data = file(path, 'rb').read()
  >     data = data.replace(old, new)
  >     file(path, 'wb').write(data)
  > EOF

  $ seteol () {
  >     if [ $1 = "LF" ]; then
  >         EOL='\n'
  >     else
  >         EOL='\r\n'
  >     fi
  > }

  $ makerepo () {
  >     seteol $1
  >     echo "% setup $1 repository"
  >     hg init repo
  >     cd repo
  >     cat > .hgeol <<EOF
  > [repository]
  > native = $1
  > [patterns]
  > mixed.txt = BIN
  > **.txt = native
  > EOF
  >     printf "first${EOL}second${EOL}third${EOL}" > a.txt
  >     hg commit --addremove -m 'checkin'
  >     echo
  >     cd ..
  > }

  $ dotest () {
  >     seteol $1
  >     echo "% hg clone repo repo-$1"
  >     hg clone --noupdate repo repo-$1
  >     cd repo-$1
  >     cat > .hg/hgrc <<EOF
  > [extensions]
  > eol =
  > [eol]
  > native = $1
  > EOF
  >     hg update
  >     echo '% a.txt'
  >     cat a.txt
  >     echo '% hg cat a.txt'
  >     hg cat a.txt
  >     printf "fourth${EOL}" >> a.txt
  >     echo '% a.txt'
  >     cat a.txt
  >     hg diff
  >     python ../switch-eol.py $1 a.txt
  >     echo '% hg diff only reports a single changed line:'
  >     hg diff
  >     echo "% reverting back to $1 format"
  >     hg revert a.txt
  >     cat a.txt
  >     printf "first\r\nsecond\n" > mixed.txt
  >     hg add mixed.txt
  >     echo "% hg commit of inconsistent .txt file marked as binary (should work)"
  >     hg commit -m 'binary file'
  >     echo "% hg commit of inconsistent .txt file marked as native (should fail)"
  >     printf "first\nsecond\r\nthird\nfourth\r\n" > a.txt
  >     hg commit -m 'inconsistent file'
  >     echo "% hg commit --config eol.only-consistent=False (should work)"
  >     hg commit --config eol.only-consistent=False -m 'inconsistent file'
  >     echo "% hg commit of binary .txt file marked as native (binary files always okay)"
  >     printf "first${EOL}\0${EOL}third${EOL}" > a.txt
  >     hg commit -m 'binary file'
  >     cd ..
  >     rm -r repo-$1
  > }

  $ makemixedrepo () {
  >     echo
  >     echo "# setup $1 repository"
  >     hg init mixed
  >     cd mixed
  >     printf "foo\r\nbar\r\nbaz\r\n" > win.txt
  >     printf "foo\nbar\nbaz\n" > unix.txt
  >     #printf "foo\r\nbar\nbaz\r\n" > mixed.txt
  >     hg commit --addremove -m 'created mixed files'
  >     echo "# setting repository-native EOLs to $1"
  >     cat > .hgeol <<EOF
  > [repository]
  > native = $1
  > [patterns]
  > **.txt = native
  > EOF
  >     hg commit --addremove -m 'added .hgeol'
  >     cd ..
  > }

  $ testmixed () {
  >     echo
  >     echo "% hg clone mixed mixed-$1"
  >     hg clone mixed mixed-$1
  >     cd mixed-$1
  >     echo '% hg status (eol extension not yet activated)'
  >     hg status
  >     cat > .hg/hgrc <<EOF
  > [extensions]
  > eol =
  > [eol]
  > native = $1
  > EOF
  >     echo '% hg status (eol activated)'
  >     hg status
  >     echo '% hg commit'
  >     hg commit -m 'synchronized EOLs'
  >     echo '% hg status'
  >     hg status
  >     cd ..
  >     rm -r mixed-$1
  > }

Basic tests

  $ makerepo LF
  % setup LF repository
  adding .hgeol
  adding a.txt
  
  $ dotest LF
  % hg clone repo repo-LF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first
  second
  third
  % hg cat a.txt
  first
  second
  third
  % a.txt
  first
  second
  third
  fourth
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % switching encoding from '\n' to '\r\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % reverting back to LF format
  first
  second
  third
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ dotest CRLF
  % hg clone repo repo-CRLF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg cat a.txt
  first
  second
  third
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  fourth\r (esc)
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % switching encoding from '\r\n' to '\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % reverting back to CRLF format
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ rm -r repo
  $ makerepo CRLF
  % setup CRLF repository
  adding .hgeol
  adding a.txt
  
  $ dotest LF
  % hg clone repo repo-LF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first
  second
  third
  % hg cat a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % a.txt
  first
  second
  third
  fourth
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % switching encoding from '\n' to '\r\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % reverting back to LF format
  first
  second
  third
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ dotest CRLF
  % hg clone repo repo-CRLF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg cat a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  fourth\r (esc)
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % switching encoding from '\r\n' to '\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % reverting back to CRLF format
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ rm -r repo

Mixed tests

  $ makemixedrepo LF
  
  # setup LF repository
  adding unix.txt
  adding win.txt
  # setting repository-native EOLs to LF
  adding .hgeol
  $ testmixed LF
  
  % hg clone mixed mixed-LF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M win.txt
  % hg commit
  % hg status
  $ testmixed CRLF
  
  % hg clone mixed mixed-CRLF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M win.txt
  % hg commit
  % hg status
  $ rm -r mixed
  $ makemixedrepo CRLF
  
  # setup CRLF repository
  adding unix.txt
  adding win.txt
  # setting repository-native EOLs to CRLF
  adding .hgeol
  $ testmixed LF
  
  % hg clone mixed mixed-LF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M unix.txt
  % hg commit
  % hg status
  $ testmixed CRLF
  
  % hg clone mixed mixed-CRLF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M unix.txt
  % hg commit
  % hg status
  $ rm -r mixed

  $ echo '[extensions]' >> $HGRCPATH
  $ echo 'eol =' >> $HGRCPATH

#if unix-permissions

Test issue2569 -- eol extension takes write lock on reading:

  $ hg init repo
  $ cd repo
  $ touch .hgeol
  $ hg status
  ? .hgeol
  $ chmod -R -w .hg
  $ sleep 1
  $ touch .hgeol
  $ hg status --traceback
  ? .hgeol
  $ chmod -R u+w .hg
  $ cd ..

#endif

Test cleverencode: and cleverdecode: aliases for win32text extension

  $ echo '[encode]' >> $HGRCPATH
  $ echo '**.txt = cleverencode:' >> $HGRCPATH
  $ echo '[decode]' >> $HGRCPATH
  $ echo '**.txt = cleverdecode:' >> $HGRCPATH

  $ hg init win32compat
  $ cd win32compat
  $ printf "foo\r\nbar\r\nbaz\r\n" > win.txt
  $ printf "foo\nbar\nbaz\n" > unix.txt
  $ hg add
  adding unix.txt
  adding win.txt
  $ hg commit -m checkin

Check that both files have LF line-endings in the repository:

  $ hg cat win.txt
  foo
  bar
  baz
  $ hg cat unix.txt
  foo
  bar
  baz

Test handling of a broken .hgeol file:

  $ touch .hgeol
  $ hg add .hgeol
  $ hg commit -m 'clean version'
  $ echo "bad" > .hgeol
  $ hg status
  warning: ignoring .hgeol file due to parse error at .hgeol:1: bad
  M .hgeol
  $ hg revert .hgeol
  warning: ignoring .hgeol file due to parse error at .hgeol:1: bad
  $ hg status
  ? .hgeol.orig

Test eol.only-consistent can be specified in .hgeol

  $ cd $TESTTMP
  $ hg init only-consistent
  $ cd only-consistent
  $ printf "first\nsecond\r\n" > a.txt
  $ hg add a.txt
  $ cat > .hgeol << EOF
  > [eol]
  > only-consistent = True
  > EOF
  $ hg commit -m 'inconsistent'
  abort: inconsistent newline style in a.txt
  
  [255]
  $ cat > .hgeol << EOF
  > [eol]
  > only-consistent = False
  > EOF
  $ hg commit -m 'consistent'


Test trailing newline

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > eol=
  > EOF

setup repository

  $ cd $TESTTMP
  $ hg init trailing
  $ cd trailing
  $ cat > .hgeol <<EOF
  > [patterns]
  > **.txt = native
  > [eol]
  > fix-trailing-newline = False
  > EOF

add text without trailing newline

  $ printf "first\nsecond" > a.txt
  $ hg commit --addremove -m 'checking in'
  adding .hgeol
  adding a.txt
  $ rm a.txt
  $ hg update -C -q
  $ cat a.txt
  first
  second (no-eol)

  $ cat > .hgeol <<EOF
  > [patterns]
  > **.txt = native
  > [eol]
  > fix-trailing-newline = True
  > EOF
  $ printf "third\nfourth" > a.txt
  $ hg commit -m 'checking in with newline fix'
  $ rm a.txt
  $ hg update -C -q
  $ cat a.txt
  third
  fourth

append a line without trailing newline

  $ printf "fifth" >> a.txt
  $ hg commit -m 'adding another line line'
  $ rm a.txt
  $ hg update -C -q
  $ cat a.txt
  third
  fourth
  fifth

  $ cd ..