Remove unnecessary sys.version_info checks from tests

Our minimum supported Python version 3.9 and these things were added
way before it was releases, so there is no need to keep them.

astor/code_gen.py

@@ -687,8 +687,6 @@ def _handle_string_constant(self, node, value, is_joined=False):
             current_line[0] = current_line[0][str_index:]
         current_line = ''.join(current_line)
 
-        has_ast_constant = sys.version_info >= (3, 6)
-
         if is_joined:
             # Handle new f-strings.  This is a bit complicated, because
             # the tree can contain subnodes that recurse back to JoinedStr
@@ -708,7 +706,7 @@ def recurse(node):
                             if value.format_spec is not None:
                                 self.write(':')
                                 recurse(value.format_spec)
-                    elif has_ast_constant and isinstance(value, ast.Constant):
+                    elif isinstance(value, ast.Constant):
                         self.write(value.value)
                     else:
                         kind = type(value).__name__

astor/rtrip.py

@@ -22,12 +22,6 @@
 
 dsttree = 'tmp_rtrip'
 
-# TODO:  Remove this workaround once we remove version 2 support
-
-
-def out_prep(s, pre_encoded=(sys.version_info[0] == 2)):
-    return s if pre_encoded else s.encode('utf-8')
-
 
 def convert(srctree, dsttree=dsttree, readonly=False, dumpall=False,
             ignore_exceptions=False, fullcomp=False):
@@ -90,7 +84,7 @@ def convert(srctree, dsttree=dsttree, readonly=False, dumpall=False,
             dstfname = os.path.join(dstpath, fname)
             try:
                 with open(dstfname, 'wb') as f:
-                    f.write(out_prep(dsttxt))
+                    f.write(dsttxt.encode('utf-8'))
             except UnicodeEncodeError:
                 badfiles.add(dstfname)
 
@@ -117,12 +111,12 @@ def convert(srctree, dsttree=dsttree, readonly=False, dumpall=False,
                 if not readonly:
                     try:
                         with open(dstfname[:-3] + '.srcdmp', 'wb') as f:
-                            f.write(out_prep(srcdump))
+                            f.write(srcdump.encode('utf-8'))
                     except UnicodeEncodeError:
                         badfiles.add(dstfname[:-3] + '.srcdmp')
                     try:
                         with open(dstfname[:-3] + '.dstdmp', 'wb') as f:
-                            f.write(out_prep(dstdump))
+                            f.write(dstdump.encode('utf-8'))
                     except UnicodeEncodeError:
                         badfiles.add(dstfname[:-3] + '.dstdmp')
                 elif dumpall:

tests/test_code_gen.py

@@ -182,8 +182,6 @@ def test(a1, a2, b1=j, b2='123', b3={}, b4=[]):
                 pass"""
         self.assertSrcRoundtrips(source)
 
-    @unittest.skipUnless(sys.version_info >= (3, 8, 0, "alpha", 4),
-                         "positional only arguments introduced in Python 3.8")
     def test_positional_only_arguments(self):
         source = """
         def test(a, b, /, c, *, d, **kwargs):
@@ -518,23 +516,6 @@ def test_assignment_expr(self):
         for case in cases:
             self.assertAstRoundtripsGtVer(case, (3, 8))
 
-    @unittest.skipUnless(sys.version_info <= (3, 3),
-                         "ast.Name used for True, False, None until Python 3.4")
-    def test_deprecated_constants_as_name(self):
-        self.assertAstEqualsSource(
-            ast.Assign(targets=[ast.Name(id='spam')], value=ast.Name(id='True')),
-            "spam = True")
-
-        self.assertAstEqualsSource(
-            ast.Assign(targets=[ast.Name(id='spam')], value=ast.Name(id='False')),
-            "spam = False")
-
-        self.assertAstEqualsSource(
-            ast.Assign(targets=[ast.Name(id='spam')], value=ast.Name(id='None')),
-            "spam = None")
-
-    @unittest.skipUnless(sys.version_info >= (3, 4),
-                         "ast.NameConstant introduced in Python 3.4")
     def test_deprecated_name_constants(self):
         self.assertAstEqualsSource(
             ast.Assign(targets=[ast.Name(id='spam')], value=ast.NameConstant(value=True)),
@@ -575,8 +556,6 @@ def test_deprecated_constant_nodes(self):
             ast.Assign(targets=[ast.Name(id='spam')], value=ast.Str("String")),
             "spam = 'String'")
 
-    @unittest.skipUnless(sys.version_info >= (3, 6),
-                         "ast.Constant introduced in Python 3.6")
     def test_constant_nodes(self):
         self.assertAstEqualsSource(
             ast.Assign(targets=[ast.Name(id='spam')], value=ast.Constant(value=3)),
@@ -634,9 +613,6 @@ def test_annassign(self):
         """
         self.assertAstRoundtripsGtVer(source, (3, 6))
 
-    @unittest.skipUnless(sys.version_info >= (3, 6),
-                         "typing and annotated assignment was introduced in "
-                         "Python 3.6")
     def test_function_typing(self):
         source = canonical("""
         def foo(x : int) ->str:
@@ -649,6 +625,7 @@ def foo(x: int) -> str:
             return i
         """)
         self.assertAstEqualsSource(ast.parse(source), target)
+        self.assertAstRoundtripsGtVer(source, (3, 6))
 
     def test_compile_types(self):
         code = '(a + b + c) * (d + e + f)\n'
@@ -996,8 +973,6 @@ def test_fstring_escaped_braces(self):
         '''
         self.assertSrcRoundtripsGtVer(source, (3, 6))
 
-    @unittest.skipUnless(sys.version_info >= (3, 8, 0, "alpha", 4),
-                         "f-string debugging introduced in Python 3.8")
     def test_fstring_debugging(self):
         source = """
         x = f'{5=}'

tests/test_misc.py

@@ -12,8 +12,6 @@
 
 class GetSymbolTestCase(unittest.TestCase):
 
-    @unittest.skipUnless(sys.version_info >= (3, 5),
-                         "ast.MatMult introduced in Python 3.5")
     def test_get_mat_mult(self):
         self.assertEqual('@', astor.get_op_symbol(ast.MatMult()))