Fix some deprecation warnings (#1301)

Author: mmatera

mathics/builtin/numpy_utils/with_numpy.py

@@ -17,6 +17,12 @@
 # INTERNAL FUNCTIONS
 #
 
+# Backward compatibility
+try:
+    ast_Str = ast.Constant
+except AttributeError:
+    ast_Str = lambda x: ast.Str(s=x)
+
 
 def _promote(x, shape):
     if isinstance(x, (int, float)):
@@ -396,9 +402,9 @@ def visit_If(self, node):
             test = node.test
             tests.append(test)
 
-            if type(test) == ast.Name:
+            if type(test) is ast.Name:
                 shapes.append(test)
-            elif type(test) == ast.Compare:
+            elif type(test) is ast.Compare:
                 if isinstance(test.left, ast.Name):
                     shapes.append(test.left)
                 elif isinstance(test.right, ast.Name):
@@ -440,7 +446,7 @@ def visit_If(self, node):
         for test, value in zip(tests, (block.value for block in blocks)):
             elements = []
             if test == _else_case_id:
-                elements.append(ast.Str(s=test))
+                elements.append(ast_Str(test))
             else:
                 elements.append(_create_ast_lambda([], test))
 

mathics/core/parser/parser.py

@@ -69,6 +69,10 @@ def unescape_string(s: str) -> str:
     For example, '"a\\n\\c"' becomes 'a\nb\nc'
     """
     assert len(s) >= 2 and s[0] == s[-1]
+    # Special cases to avoid the Deprecation Warning
+    if s in ('"\\!"', '"\\$"', '"\\W+"', '"\\d"'):
+        return s[1:-1]
+
     s = s.encode("raw_unicode_escape").decode("unicode_escape")
     return s[1:-1]
 
@@ -915,7 +919,7 @@ def e_RawLeftBracket(self, expr, token: Token, p: int) -> Optional[Node]:
             self.bracket_depth -= 1
 
             if self.is_inside_rowbox:
-                # Hande function calls inside a RowBox.
+                # Handle function calls inside a RowBox.
                 result = Node("List", expr, String("["), *seq, String("]"))
             else:
                 result = Node(expr, *seq)