Restore doctesting of non-library files

[sagetrac-fwclarke]

Since #9739, it has not been possible to doctest non-library files (if, as is likely, they contain definitions which get tested). This is because in sage-doctest the same name is used for:

1. the python file which is created in SAGE_TESTDIR (a copy of, or a preparsed version of, the file being tested), and
2. the file which loads the previous file and contains the extracted doctests.

As a result, the first file is overwritten by the second, and then loads itself. Thus definitions from the original file are not available to the doctests.

CC: @jhpalmieri

Component: doctest coverage

Reviewer: Francis Clarke

Issue created by migration from https://trac.sagemath.org/ticket/12704

[sagetrac-fwclarke]

comment:1

Attachment: trac_12704-doctest_non-library_files.patch.gz

The one-line patch solves the problem.

[sagetrac-fwclarke]

Author: Francis Clarke

[jhpalmieri]

comment:2

I think this is a duplicate of #12069.

[sagetrac-fwclarke]

comment:3

Replying to @jhpalmieri:

I think this is a duplicate of #12069 .

Indeed, it is; it should be closed.

Sorry for missing #12069, which does a more thorough job. Perhaps it should be added to #11337.

[jhpalmieri]

comment:4

I just added #12069 to #11337.

[jdemeyer]

Reviewer: Francis Clarke

[jdemeyer]

Changed author from Francis Clarke to none