_default_python method added

Author: davidsanfal

conan/tools/system/pip_manager.py

@@ -24,10 +24,13 @@ def generate(self):
         env.prepend_path("PATH", self.bin_dir)
         env.vars(self._conanfile).save_script(self.env_name)
 
-    def _create_venv(self):
+    @staticmethod
+    def _default_python():
         default_python = shutil.which('python') if platform.system() == "Windows" else shutil.which('python3')
-        python_interpreter = self._conanfile.conf.get("tools.system.pipenv:python_interpreter",
-                                                      default=os.path.realpath(default_python) if default_python else None)
+        return os.path.realpath(default_python) if default_python else None
+
+    def _create_venv(self):
+        python_interpreter = self._conanfile.conf.get("tools.system.pipenv:python_interpreter") or self._default_python()
         if not python_interpreter:
             raise ConanException("PipEnv could not find a Python executable path."
                                  "Please set 'tools.system.pipenv:python_interpreter' to '</your/python/full/path>' "

test/integration/tools/system/pip_manager_test.py

@@ -8,10 +8,12 @@
 from conan.test.utils.mocks import ConanFileMock
 
 
-def test_pipenv_conf():
+@patch('shutil.which')
+def test_pipenv_conf(mock_shutil_which):
     # https://github.com/conan-io/conan/issues/11661
     conanfile = ConanFileMock()
     conanfile.settings = Settings()
+    mock_shutil_which.side_effect = Exception()
     conanfile.conf.define("tools.system.pipenv:python_interpreter", "/python/interpreter/from/config")
     result = "/python/interpreter/from/config -m venv"
     pipenv = PipEnv(conanfile, "testenv")