Make deprecated_function_alias print the whole module path when it differs from the original

[defeo]

Currently

sage: from sage.misc.misc import deprecated_function_alias
sage: a = deprecated_function_alias(sqrt, "Version ?")
sage: a(5)
...
DeprecationWarning: (Since Version ?) a is deprecated. Please use sqrt instead.
sqrt(5)

which is misleading because the user would expect to find sqrt in the same module as a.

With this patch

sage: from sage.misc.misc import deprecated_function_alias
sage: a = deprecated_function_alias(sqrt, "Version ?")
sage: a(5)
...
DeprecationWarning: (Since Version ?) a is deprecated. Please use sage.functions.other.sqrt instead.
sqrt(5)

There's no change in deprecating methods.

Apply:

1. trac_11585_deprecated_function_alias-rc2.patch​

[rbeezer]

Looks good. Passes long tests on 4.7.1.alpha3. I've cc'ed Florent Hivert in case he wants to add anything. I've also added an "Apply" section to the description for the release manager.

Two minor formatting items need attention.

Line 2287: Trac #11585::

You need a blank line after the double-colon to make the verbatim text format properly.

You can test documentation via sage -docbuild reference html after a fresh build (sage -b) and then viewing the resulting HTML file.

Line 2299:

if module is None: module_name = '__main__'
else: module_name = module.__name__

should be formatted as

if module is None:
    module_name = '__main__'
else:
    module_name = module.__name__

See http://www.sagemath.org/doc/developer/conventions.html

which references: ​http://www.python.org/dev/peps/pep-0008/

(look shortly after "Compound statements")

[defeo]

Modified as requested by rbeezer. Apply second patch only (sorry for the mispelling in the first patch).

[rbeezer]

Luca,

Looks good - thanks for the improvement.

I am going to switch this to positive review, but Florent Hivert should feel free to get in on this just in case he sees something.

Rob

[hivert]

I've no particular comments concerning this patch. We should start to actually remove deprecated things from sage, but this is another problem. Ready to go.

Florent

[jdemeyer]

This needs to be rebased to sage-4.7.1.rc1

[defeo]

Rebased against rc1

[hivert]

If you just rebased the patch, you are allowed to put a positive review yourself. Anyway, I made a short re-review and found it Ok.

Florent

[jdemeyer]

This patch greatly increases the Sage startup time. On sage.math.washington.edu, before the patch it is roughly 1.4s and after the patch 2.2s.

[defeo]

Ouch! This single line is responsible for it:

module = inspect.getmodule(inspect.stack()[1][0])

In fact, there's about 40 calls to deprecated_function_alias in 4.7.1.rc2; on my laptop:

sage: import inspect
sage: timeit('inspect.stack()[1][0]')
25 loops, best of 3: 18.4 ms per loop

The fact is, I don't know how to obtain the name of the module where the call to deprecated_function_alias happened without inspecting the stack. Any ideas?

[hivert]

The fact is, I don't know how to obtain the name of the module where the call to deprecated_function_alias happened without inspecting the stack. Any ideas?

I don't have to investigate further now but I think you don't need the full stack but only the top of it. Using

inspect.getframeinfo(sys._getframe(1),1)

should be much faster...

[hivert]

Here is what I think is a good solution inspect.currentframe(1) does the same as inspect.stack()[1][0] only 400 time faster:

sage: import inspect
sage: inspect.getmodule(inspect.stack()[1][0]) == inspect.getmodule(inspect.currentframe(1))
True
sage: timeit('inspect.getmodule(inspect.stack()[1][0])')
25 loops, best of 3: 15.6 ms per loop
sage: timeit('inspect.getmodule(inspect.currentframe(1))')
625 loops, best of 3: 40.7 µs per loop

I'm updating the patch accordingly.

Florent

[hivert]

Unfortunately, the problem is not with the stack:

Before any patch:

sage.all: 0.987 (None)

After the rc1 patch

sage.all: 1.805 (None)

After the rc2 patch

sage.all: 1.692 (None)

It's better but still too much.

Florent

[hivert]

Got it !!! We don't need the module but only its name. One can get it using the filename of the code which is currently executed. Here is the diff

sage/misc/misc.py

@@ -2387 +2387 @@
      - Florent Hivert (2009-11-23), with the help of Mike Hansen.
      - Luca De Feo (2011-07-11), printing the full module path when different from old path
     """
-    module = inspect.getmodule(inspect.currentframe(1))
-    if module is None:
+    module_name = inspect.getmodulename(
+        inspect.currentframe(1).f_code.co_filename)
+    if module_name is None:
         module_name = '__main__'
-    else:
-        module_name = module.__name__
     return DeprecatedFunctionAlias(func, version, module_name)

The new startup time is ok !

sage.all: 0.962 (None)

Please review.

Florent

[defeo]

Thanks for sorting this out, Florent.

I tried it: it solves the startup issue and all tests pass. Can I give positive review, or shall we ask someone else to review it?

Luca

[hivert]

I tried it: it solves the startup issue and all tests pass. Can I give positive review, or shall we ask someone else to review it?

Sure you can. Your code has already been reviewed twice so it is Ok to go. Given that, only my change has to be reviewed, it could be done by person which is not me. I think you are the perfect person to do that. So please set the positive review if you think my change is Ok.