On Ubuntu 18.04, with few optional/external packages, I get
Running doctests with ID 2022-02-07-17-21-38-2cb12a08.
Git branch: develop
Using --optional=4ti2,build,ccache,cryptominisat,debian,debugpy,dot2tex,e_antic,external,fricas,glucose,latte_int,lidia,normaliz,notedown,pandoc_attributes,pip,pycosat,pynormaliz,rst2ipynb,sage,sage_numerical_backends_coin,sage_spkg
[...]
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sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/calculus/calculus.py # 3 doctests failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/combinat/designs/incidence_structures.py # 1 doctest failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/databases/findstat.py # 12 doctests failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/databases/oeis.py # 1 doctest failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/graphs/generic_graph.py # 2 doctests failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/graphs/graph.py # 3 doctests failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/interfaces/mathematica.py # 1 doctest failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/symbolic/integration/external.py # 8 doctests failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/symbolic/integration/integral.py # 2 doctests failed
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/tests/cmdline.py # 1 doctest failed
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Features detected for doctesting: dvipng,ffmpeg,graphviz,imagemagick,internet,latex,latex_package_tkz_graph,lualatex,octave,pandoc,pdf2svg,pdflatex,sage.combinat,sage.geometry.polyhedron,sage.graphs,sage.groups,sage.plot,sage.rings.number_field,sage.rings.padics,sage.rings.real_double,sage.symbolic,sagemath_doc_html,sphinx,xelatex
When rerunning failed tests, only the following failures reproduce:
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sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/combinat/designs/incidence_structures.py # 1 doctest failed
sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/databases/findstat.py # 14 doctests failed
sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/databases/oeis.py # 3 doctests failed
sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/graphs/generic_graph.py # 2 doctests failed
sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/graphs/graph.py # 3 doctests failed
sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/interfaces/mathematica.py # 1 doctest failed
sage -t --long --random-seed=189990558529197088173411804645557675259 src/sage/tests/cmdline.py # 1 doctest failed
----------------------------------------------------------------------
Features detected for doctesting: graphviz,internet,latex,pandoc,sage.groups,sage.symbolic
which means failures with calculus.py and sage/symbolic disappeared. Indeed, they were related to a problem with access to internet:
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/calculus/calculus.py
**********************************************************************
File "src/sage/calculus/calculus.py", line 1297, in sage.calculus.calculus.limit
Failed example:
limit(pi+log(x)/x,x=oo, algorithm='mathematica_free') # optional - internet
Exception raised:
Traceback (most recent call last):
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/doctest/forker.py", line 694, in _run
self.compile_and_execute(example, compiler, test.globs)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/doctest/forker.py", line 1088, in compile_and_execute
exec(compiled, globs)
File "<doctest sage.calculus.calculus.limit[43]>", line 1, in <module>
limit(pi+log(x)/x,x=oo, algorithm='mathematica_free') # optional - internet
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/calculus/calculus.py", line 1454, in limit
return mma_free_limit(ex, v, a, dir)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/calculus/calculus.py", line 1502, in mma_free_limit
json_page_data = request_wolfram_alpha(input)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/interfaces/mathematica.py", line 1142, in request_wolfram_alpha
resp = opener.open(req)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 523, in open
response = meth(req, response)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 632, in http_response
response = self.parent.error(
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 561, in error
return self._call_chain(*args)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 494, in _call_chain
result = func(*args)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 641, in http_error_default
raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 500: Proxy Error
**********************************************************************
sage -t --long --random-seed=181853543176117186194592858524549391076 src/sage/symbolic/integration/external.py
**********************************************************************
File "src/sage/symbolic/integration/external.py", line 79, in sage.symbolic.integration.external.mma_free_integrator
Failed example:
mma_free_integrator(sin(x), x) # optional - internet
Exception raised:
Traceback (most recent call last):
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/doctest/forker.py", line 694, in _run
self.compile_and_execute(example, compiler, test.globs)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/doctest/forker.py", line 1088, in compile_and_execute
exec(compiled, globs)
File "<doctest sage.symbolic.integration.external.mma_free_integrator[1]>", line 1, in <module>
mma_free_integrator(sin(x), x) # optional - internet
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/symbolic/integration/external.py", line 126, in mma_free_integrator
json_page_data = request_wolfram_alpha(input)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/site-packages/sage/interfaces/mathematica.py", line 1142, in request_wolfram_alpha
resp = opener.open(req)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 523, in open
response = meth(req, response)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 632, in http_response
response = self.parent.error(
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 561, in error
return self._call_chain(*args)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 494, in _call_chain
result = func(*args)
File "/home/slabbe/GitBox/sage/local/lib/python3.9/urllib/request.py", line 641, in http_error_default
raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 500: Proxy Error
**********************************************************************
In summary, no new failures to report.