bpo-36763: Add _PyCoreConfig_InitPythonConfig() (GH-13388)

Add new functions to get the Python interpreter behavior:

* _PyPreConfig_InitPythonConfig()
* _PyCoreConfig_InitPythonConfig()

Add new functions to get an isolated configuration:

* _PyPreConfig_InitIsolatedConfig()
* _PyCoreConfig_InitIsolatedConfig()

Replace _PyPreConfig_INIT and _PyCoreConfig_INIT with new functions
_PyPreConfig_Init() and _PyCoreConfig_Init().

_PyCoreConfig: set configure_c_stdio and parse_argv to 0 by default
to behave as Python 3.6 in the default configuration.

_PyCoreConfig_Read() no longer sets coerce_c_locale_warn to 1 if it's
equal to 0. coerce_c_locale_warn must now be set to -1 (ex: using
_PyCoreConfig_InitPythonConfig()) to enable C locale coercion
warning.

Add unit tests for _PyCoreConfig_InitPythonConfig()
and _PyCoreConfig_InitIsolatedConfig().

Changes:

* Rename _PyCoreConfig_GetCoreConfig() to _PyPreConfig_GetCoreConfig()
* Fix core_read_precmdline(): handle parse_argv=0
* Fix _Py_PreInitializeFromCoreConfig(): pass coreconfig.argv
  to _Py_PreInitializeFromPyArgv(), except if parse_argv=0

1 files changed, 2 insertions, 1 deletions

diff --git a/Python/pathconfig.c b/Python/pathconfig.c
index 2fcb816..c8c69eb 100644
--- a/Python/pathconfig.c
+++ b/Python/pathconfig.c
@@ -392,7 +392,8 @@ pathconfig_global_init(void)
     }
 
     _PyInitError err;
-    _PyCoreConfig config = _PyCoreConfig_INIT;
+    _PyCoreConfig config;
+    _PyCoreConfig_Init(&config);
 
     err = _PyCoreConfig_Read(&config);
     if (_Py_INIT_FAILED(err)) {