This is because the Read the Docs configuration file added in #732 only specifies to install the requirements in docs/requirements.txt, namely sphinx and sphinx_rtd_theme.
This results in VCR.py itself not being installed when building the documentation, with autodoc failing to import from vcr, as can be seen from the v5.1.0 build:
WARNING: autodoc: failed to import module 'config' from module 'vcr'; the following exception was raised:
No module named 'vcr'
WARNING: autodoc: failed to import module 'cassette' from module 'vcr'; the following exception was raised:
No module named 'vcr'
WARNING: autodoc: failed to import module 'matchers' from module 'vcr'; the following exception was raised:
No module named 'vcr'
WARNING: autodoc: failed to import module 'filters' from module 'vcr'; the following exception was raised:
No module named 'vcr'
WARNING: autodoc: failed to import module 'request' from module 'vcr'; the following exception was raised:
No module named 'vcr'
WARNING: autodoc: failed to import module 'serialize' from module 'vcr'; the following exception was raised:
No module named 'vcr'
WARNING: autodoc: failed to import module 'patch' from module 'vcr'; the following exception was raised:
No module named 'vcr'
The API documentation for v5.1.0 is bare.
This is because the Read the Docs configuration file added in #732 only specifies to install the requirements in docs/requirements.txt, namely sphinx and sphinx_rtd_theme.
This results in VCR.py itself not being installed when building the documentation, with autodoc failing to import from
vcr, as can be seen from the v5.1.0 build: