Mercurial > hg
view tests/test-diff-ignore-whitespace.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.
| author | Chris Jerdonek <chris.jerdonek@gmail.com> |
|---|---|
| date | Wed, 04 Dec 2013 20:38:27 -0800 |
| parents | 405b6bd015df |
| children | da07367d683b |
line wrap: on
line source
GNU diff is the reference for all of these results. Prepare tests: $ echo '[alias]' >> $HGRCPATH $ echo 'ndiff = diff --nodates' >> $HGRCPATH $ hg init $ printf 'hello world\ngoodbye world\n' >foo $ hg ci -Amfoo -ufoo adding foo Test added blank lines: $ printf '\nhello world\n\ngoodbye world\n\n' >foo >>> two diffs showing three added lines <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ + hello world + goodbye world + $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ + hello world + goodbye world + >>> no diffs <<< $ hg ndiff -B $ hg ndiff -Bb Test added horizontal space first on a line(): $ printf '\t hello world\ngoodbye world\n' >foo >>> four diffs showing added space first on the first line <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world + hello world goodbye world $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world + hello world goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world + hello world goodbye world $ hg ndiff -Bb diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world + hello world goodbye world Test added horizontal space last on a line: $ printf 'hello world\t \ngoodbye world\n' >foo >>> two diffs showing space appended to the first line <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world +hello world goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world +hello world goodbye world >>> no diffs <<< $ hg ndiff -b $ hg ndiff -Bb Test added horizontal space in the middle of a word: $ printf 'hello world\ngood bye world\n' >foo >>> four diffs showing space inserted into "goodbye" <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ hello world -goodbye world +good bye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ hello world -goodbye world +good bye world $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ hello world -goodbye world +good bye world $ hg ndiff -Bb diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ hello world -goodbye world +good bye world Test increased horizontal whitespace amount: $ printf 'hello world\ngoodbye\t\t \tworld\n' >foo >>> two diffs showing changed whitespace amount in the last line <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ hello world -goodbye world +goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ hello world -goodbye world +goodbye world >>> no diffs <<< $ hg ndiff -b $ hg ndiff -Bb Test added blank line with horizontal whitespace: $ printf 'hello world\n \t\ngoodbye world\n' >foo >>> three diffs showing added blank line with horizontal space <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ hello world + goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ hello world + goodbye world $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ hello world + goodbye world >>> no diffs <<< $ hg ndiff -Bb Test added blank line with other whitespace: $ printf 'hello world\n \t\ngoodbye world \n' >foo >>> three diffs showing added blank line with other space <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ -hello world -goodbye world +hello world + +goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ -hello world -goodbye world +hello world + +goodbye world $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ hello world + goodbye world >>> no diffs <<< $ hg ndiff -Bb Test whitespace changes: $ printf 'helloworld\ngoodbye\tworld \n' >foo >>> four diffs showing changed whitespace <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world -goodbye world +helloworld +goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world -goodbye world +helloworld +goodbye world $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world +helloworld goodbye world $ hg ndiff -Bb diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,2 @@ -hello world +helloworld goodbye world >>> no diffs <<< $ hg ndiff -w Test whitespace changes and blank lines: $ printf 'helloworld\n\n\n\ngoodbye\tworld \n' >foo >>> five diffs showing changed whitespace <<< $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ -hello world -goodbye world +helloworld + + + +goodbye world $ hg ndiff -B diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ -hello world -goodbye world +helloworld + + + +goodbye world $ hg ndiff -b diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ -hello world +helloworld + + + goodbye world $ hg ndiff -Bb diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ -hello world +helloworld + + + goodbye world $ hg ndiff -w diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,5 @@ hello world + + + goodbye world >>> no diffs <<< $ hg ndiff -wB Test \r (carriage return) as used in "DOS" line endings: $ printf 'hello world\r\n\r\ngoodbye\rworld\n' >foo $ hg ndiff diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ -hello world -goodbye world +hello world\r (esc) +\r (esc) +goodbye\r (no-eol) (esc) world No completely blank lines to ignore: $ hg ndiff --ignore-blank-lines diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ -hello world -goodbye world +hello world\r (esc) +\r (esc) +goodbye\r (no-eol) (esc) world Only new line noticed: $ hg ndiff --ignore-space-change diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ hello world +\r (esc) goodbye world $ hg ndiff --ignore-all-space diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ hello world +\r (esc) goodbye world New line not noticed when space change ignored: $ hg ndiff --ignore-blank-lines --ignore-all-space Do not ignore all newlines, only blank lines $ printf 'hello \nworld\ngoodbye world\n' > foo $ hg ndiff --ignore-blank-lines diff -r 540c40a65b78 foo --- a/foo +++ b/foo @@ -1,2 +1,3 @@ -hello world +hello +world goodbye world Test hunk offsets adjustments with --ignore-blank-lines $ hg revert -aC reverting foo $ printf '\nb\nx\nd\n' > a $ printf 'b\ny\nd\n' > b $ hg add a b $ hg ci -m add $ hg cat -r . a > b $ hg cat -r . b > a $ hg diff -B --nodates a > ../diffa $ cat ../diffa diff -r 0e66aa54f318 a --- a/a +++ b/a @@ -1,4 +1,4 @@ b -x +y d $ hg diff -B --nodates b > ../diffb $ cat ../diffb diff -r 0e66aa54f318 b --- a/b +++ b/b @@ -1,3 +1,3 @@ b -y +x d $ hg revert -aC reverting a reverting b $ hg import --no-commit ../diffa applying ../diffa $ hg revert -aC reverting a $ hg import --no-commit ../diffb applying ../diffb $ hg revert -aC reverting b