python module: implicitly add python dep to extensions

If there isn't a preexisting dependency on python, append one. It's
almost assuredly needed, so just do the right thing out of the box.

1 files changed, 13 insertions, 0 deletions

diff --git a/docs/markdown/snippets/python-extension-module-implicit-dependency.md b/docs/markdown/snippets/python-extension-module-implicit-dependency.md
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+## Python extension modules now depend on the python library by default
+
+Python extension modules are usually expected to link to the python library
+and/or its headers in order to build correctly (via the default `embed: false`,
+which may not actually link to the library itself). This means that every
+single use of `.extension_module()` needed to include the `dependencies:
+py_installation.dependency()` kwarg explicitly.
+
+In the interest of doing the right thing out of the box, this is now the
+default for extension modules that don't already include a dependency on
+python. This is not expected to break anything, because it should always be
+needed. Nevertheless, `py_installation.dependency().partial_dependency()` will
+be detected as already included while providing no compile/link args.