[1.8.x] Fixed #24979 -- Removed usage of inspect.getargspec().

Backport of 3872a33132a4bb6aa22b237927597bbfdf6f21d7 from master

3 files changed, 18 insertions, 12 deletions

diff --git a/django/db/migrations/writer.py b/django/db/migrations/writer.py
index 1bed59b3ef..779c842af3 100644
--- a/django/db/migrations/writer.py
+++ b/django/db/migrations/writer.py
@@ -3,7 +3,6 @@ from __future__ import unicode_literals
 import collections
 import datetime
 import decimal
-import inspect
 import math
 import os
 import re
@@ -19,6 +18,7 @@ from django.utils import datetime_safe, six
 from django.utils._os import upath
 from django.utils.encoding import force_text
 from django.utils.functional import Promise
+from django.utils.inspect import get_func_args
 from django.utils.timezone import utc
 from django.utils.version import get_docs_version
 
@@ -97,7 +97,7 @@ class OperationWriter(object):
 
         imports = set()
         name, args, kwargs = self.operation.deconstruct()
-        argspec = inspect.getargspec(self.operation.__init__)
+        operation_args = get_func_args(self.operation.__init__)
 
         # See if this operation is in django.db.migrations. If it is,
         # We can just use the fact we already have that imported,
@@ -110,16 +110,15 @@ class OperationWriter(object):
 
         self.indent()
 
-        # Start at one because argspec includes "self"
-        for i, arg in enumerate(args, 1):
+        for i, arg in enumerate(args):
             arg_value = arg
-            arg_name = argspec.args[i]
+            arg_name = operation_args[i]
             _write(arg_name, arg_value)
 
         i = len(args)
         # Only iterate over remaining arguments
-        for arg_name in argspec.args[i + 1:]:
-            if arg_name in kwargs:
+        for arg_name in operation_args[i:]:
+            if arg_name in kwargs:  # Don't sort to maintain signature order
                 arg_value = kwargs[arg_name]
                 _write(arg_name, arg_value)
 
diff --git a/django/db/models/fields/files.py b/django/db/models/fields/files.py
index 73c67bef81..d6c1eaf49f 100644
--- a/django/db/models/fields/files.py
+++ b/django/db/models/fields/files.py
@@ -1,7 +1,6 @@
 import datetime
 import os
 import warnings
-from inspect import getargspec
 
 from django import forms
 from django.core import checks
@@ -13,6 +12,7 @@ from django.db.models.fields import Field
 from django.utils import six
 from django.utils.deprecation import RemovedInDjango110Warning
 from django.utils.encoding import force_str, force_text
+from django.utils.inspect import func_supports_parameter
 from django.utils.translation import ugettext_lazy as _
 
 
@@ -89,8 +89,7 @@ class FieldFile(File):
     def save(self, name, content, save=True):
         name = self.field.generate_filename(self.instance, name)
 
-        args, varargs, varkw, defaults = getargspec(self.storage.save)
-        if 'max_length' in args:
+        if func_supports_parameter(self.storage.save, 'max_length'):
             self.name = self.storage.save(name, content, max_length=self.field.max_length)
         else:
             warnings.warn(
diff --git a/django/db/utils.py b/django/db/utils.py
index 2261a69f71..47dd5fd937 100644
--- a/django/db/utils.py
+++ b/django/db/utils.py
@@ -333,8 +333,16 @@ class ConnectionRouter(object):
                 # If the router doesn't have a method, skip to the next one.
                 continue
 
-            argspec = inspect.getargspec(method)
-            if len(argspec.args) == 3 and not argspec.keywords:
+            if six.PY3:
+                sig = inspect.signature(router.allow_migrate)
+                has_deprecated_signature = not any(
+                    p.kind == inspect.Parameter.VAR_KEYWORD for p in sig.parameters.values()
+                )
+            else:
+                argspec = inspect.getargspec(router.allow_migrate)
+                has_deprecated_signature = len(argspec.args) == 3 and not argspec.keywords
+
+            if has_deprecated_signature:
                 warnings.warn(
                     "The signature of allow_migrate has changed from "
                     "allow_migrate(self, db, model) to "