fix(bash): exclude PWD environment variable from backup/restore (#142)

Close #142

ddb/feature/shell/actions.py

@@ -246,6 +246,7 @@ def execute(self):
         config_environ.update(config.env_additions)
 
         to_encode_environ = dict(initial_environ)
+        self.shell.before_environ_backup(to_encode_environ)
         os.environ.update(config_environ)
         os.environ[_env_environ_backup] = encode_environ_backup(to_encode_environ)
         os.environ[config.env_prefix + '_PROJECT_HOME'] = config.paths.project_home

ddb/feature/shell/integrations.py

@@ -62,6 +62,12 @@ def evaluate_script(self, script_filepath) -> Iterable[str]:
         Get the command to evaluate the script inside the current shell context.
         """
 
+    def before_environ_backup(self, environ: Dict[str, str]):
+        """
+        Alter environment variables before backup. This should be used to remove for saved environ variables that
+        should not be restored on deactivation.
+        """
+
     def header(self) -> Iterable[str]:  # pylint:disable=no-self-use
         """
         Returns header of script
@@ -100,6 +106,11 @@ def set_environment_variable(self, key, value):
     def remove_environment_variable(self, key):
         yield "unset " + self._sanitize_key(key)
 
+    def before_environ_backup(self, environ):
+        for key in ('PWD',):
+            if key in environ:
+                del environ['PWD']
+
     def remove_all_binary_shims(self, shims_path: str):
         shims = []