ENH: Switch to a negative flag

Also remove FutureWarning and update documentation

Co-authored-by: Ralf Gommers <ralf.gommers@gmail.com>

5 files changed, 13 insertions, 8 deletions

diff --git a/doc/source/f2py/buildtools/index.rst b/doc/source/f2py/buildtools/index.rst
index 5121c3775..08e0763fe 100644
--- a/doc/source/f2py/buildtools/index.rst
+++ b/doc/source/f2py/buildtools/index.rst
@@ -80,8 +80,10 @@ Signature files
 
 .. note::
 
-   To generate every possible input for a given standard (F77 or F90)
-   ``--empty-gen`` can be passed to ``f2py`` from NumPy version ``1.22.4``.
+   From NumPy ``1.22.4`` onwards, ``f2py`` will deterministically generate
+   wrapper files based on the input file Fortran standard (F77 or greater).
+   ``--no-empty-gen`` can be passed to ``f2py`` to restore the previous
+   behaviour of only generating wrappers when needed by the input .
 
 
 In theory keeping the above requirements in hand, any build system can be
diff --git a/doc/source/f2py/buildtools/meson.rst b/doc/source/f2py/buildtools/meson.rst
index 2c5a2395c..59a96ab45 100644
--- a/doc/source/f2py/buildtools/meson.rst
+++ b/doc/source/f2py/buildtools/meson.rst
@@ -85,8 +85,10 @@ for reasons discussed in :ref:`f2py-bldsys`.
 
 .. note::
 
-   To generate every possible input for a given standard (F77 or F90)
-   ``--empty-gen`` can be passed to ``f2py`` from NumPy version ``1.22.4``.
+   From NumPy ``1.22.4`` onwards, ``f2py`` will deterministically generate
+   wrapper files based on the input file Fortran standard (F77 or greater).
+   ``--no-empty-gen`` can be passed to ``f2py`` to restore the previous
+   behaviour of only generating wrappers when needed by the input .
 
 However, we can augment our workflow in a straightforward to take into account
 files for which the outputs are known when the build system is set up.
diff --git a/doc/source/f2py/code/meson.build b/doc/source/f2py/code/meson.build
index 36c841fd3..b84bf52a9 100644
--- a/doc/source/f2py/code/meson.build
+++ b/doc/source/f2py/code/meson.build
@@ -24,7 +24,7 @@ fibby_source = custom_target('fibbymodule.c',
                             input : ['fib1.f'], # .f so no F90 wrappers
                             output : ['fibbymodule.c', 'fibby-f2pywrappers.f'],
                             command : [ py3, '-m', 'numpy.f2py', '@INPUT@',
-                            '-m', 'fibby', '--lower', '--empty-gen' ]
+                            '-m', 'fibby', '--lower']
                             )
 
 inc_np = include_directories(incdir_numpy, incdir_f2py)
diff --git a/doc/source/f2py/code/meson_upd.build b/doc/source/f2py/code/meson_upd.build
index a2b2badea..44d69d182 100644
--- a/doc/source/f2py/code/meson_upd.build
+++ b/doc/source/f2py/code/meson_upd.build
@@ -24,7 +24,7 @@ fibby_source = custom_target('fibbymodule.c',
                             input : ['fib1.f'], # .f so no F90 wrappers
                             output : ['fibbymodule.c', 'fibby-f2pywrappers.f'],
                             command : [ py3, '-m', 'numpy.f2py', '@INPUT@',
-                            '-m', 'fibby', '--lower', '--empty-gen' ])
+                            '-m', 'fibby', '--lower'])
 
 inc_np = include_directories(incdir_numpy, incdir_f2py)
 
diff --git a/doc/source/f2py/usage.rst b/doc/source/f2py/usage.rst
index 7541be34b..d3e9db22a 100644
--- a/doc/source/f2py/usage.rst
+++ b/doc/source/f2py/usage.rst
@@ -224,8 +224,9 @@ Other options
     Run quietly.
   ``--verbose``
     Run with extra verbosity.
-  ``--empty-gen``
-    Generate all possible (empty) wrapper files.
+  ``--no-empty-gen``
+    Do not generate wrapper files unless required by the inputs.
+    This is a backwards compatibility flag to restore pre 1.22.4 behavior.
   ``-v``
     Print the F2PY version and exit.