Remove lists as default arguments in functions

Signed-off-by: Evangelos Lamprou <e.lamprou@upnet.gr>

compiler/definitions/ir/nodes/dfs_split_reader.py

@@ -3,8 +3,12 @@
 
 class DFSSplitReader(DFGNode):
     def __init__(self, inputs, outputs, com_name, com_category, 
-                 com_options = [], com_redirs = [], com_assignments=[]):
+                 com_options = None, com_redirs = None, com_assignments=None):
 
+        com_options = [] if com_options is None else com_options
+        com_redirs = [] if com_redirs is None else com_redirs
+        com_assignments = [] if com_assignments is None else com_assignments
+
         super().__init__(inputs, outputs, com_name, com_category,
                          com_options=com_options, 
                          com_redirs=com_redirs, 

compiler/definitions/ir/nodes/hdfs_cat.py

@@ -2,7 +2,11 @@
 
 class HDFSCat(DFGNode):
     def __init__(self, inputs, outputs, com_name, com_category,
-                 com_options = [], com_redirs = [], com_assignments=[]):
+                 com_options = None, com_redirs = None, com_assignments=None):
+        com_options = [] if com_options is None else com_options
+        com_redirs = [] if com_redirs is None else com_redirs
+        com_assignments = [] if com_assignments is None else com_assignments
+
         assert(str(com_name) == "hdfs")
         assert(str(com_options[0][1]) == "dfs" and str(com_options[1][1]) == "-cat") 
         super().__init__(inputs, outputs, com_name, com_category,

compiler/definitions/ir/nodes/remote_pipe.py

@@ -2,7 +2,10 @@
 
 class RemotePipe(DFGNode):
     def __init__(self, inputs, outputs, com_name, com_category,
-                 com_options = [], com_redirs = [], com_assignments=[]):
+                 com_options = None, com_redirs = None, com_assignments=None):
+        com_options = [] if com_options is None else com_options
+        com_redirs = [] if com_redirs is None else com_redirs
+        com_assignments = [] if com_assignments is None else com_assignments
         super().__init__(inputs, outputs, com_name, com_category,
                          com_options=com_options, 
                          com_redirs=com_redirs, 

compiler/dspash/worker_manager.py

@@ -78,8 +78,8 @@ def host(self):
         return self._host
 
 class WorkersManager():
-    def __init__(self, workers: WorkerConnection = []):
-        self.workers = workers
+    def __init__(self, workers: WorkerConnection = None):
+        self.workers = [] if workers is None else workers
         self.host = socket.gethostbyname(socket.gethostname())
         self.args = copy.copy(config.pash_args)
         # Required to create a correct multi sink graph

compiler/ir.py

@@ -185,7 +185,9 @@ def add_var_for_descriptor(operand):
 
 
 def compile_command_to_DFG(fileIdGen, command, options,
-                           redirections=[]):
+                           redirections=None):
+    redirections = [] if redirections is None else redirections
+
     command_invocation: CommandInvocationInitial = parse_arg_list_to_command_invocation(command, options)
     io_info: InputOutputInfo = get_input_output_info_from_cmd_invocation_util(command_invocation)
     if io_info is None:

compiler/shell_ast/ast_util.py

@@ -97,7 +97,8 @@ def redir_stdout_to_file(arg):
 def redir_file_to_stdin(arg):
     return make_kv("File",["From", 0, arg])
 
-def make_background(body, redirections=[]):
+def make_background(body, redirections=None):
+    redirections = [] if redirections is None else redirections
     lineno = 0
     node = make_kv("Background", [lineno, body, redirections])
     return node
@@ -106,12 +107,15 @@ def make_backquote(node):
     node = make_kv("B", node)
     return node
 
-def make_subshell(body, redirections=[]):
+def make_subshell(body, redirections=None):
+    redirections = [] if redirections is None else redirections
     lineno = 0
     node = make_kv("Subshell", [lineno, body, redirections])
     return node
 
-def make_command(arguments, redirections=[], assignments=[]):
+def make_command(arguments, redirections=None, assignments=None):
+    assignments = [] if assignments is None else assignments
+    redirections = [] if redirections is None else redirections
     lineno = 0
     node = make_kv("Command", [lineno, assignments, arguments, redirections])
     return node
@@ -224,4 +228,4 @@ def make_echo_ast(argument, var_file_path):
     line_number = 0
     node = make_kv('Command', [line_number, [], arguments, []])
     nodes.append(node)
-    return nodes
+    return nodes