fix differentation tests

tests/0.D/test_differentiation.py

@@ -23,10 +23,12 @@ def sympy_to_us(expr):
     return expr.replace("**", "^").replace("exp(", "e(").replace("atan(", "arctan(")
 
 def pprint(expr, pr=True):
-    orig = expr_to_string(expr)
-    result = expr_to_string(oursimplify(expr), use_parens=False)
-    result_parens = expr_to_string(oursimplify(expr), use_parens=True)
+    print(expr)
+    orig = expr
+    result = expr_to_string(oursimplify(parse(expr)), use_parens=False)
+    result_parens = expr_to_string(oursimplify(parse(expr)), use_parens=True)
     ref = nsimplify(expand(sympify(us_to_sympy(orig))))
+    print(result, ref, orig)
     if pr:
         print(orig, end=" ")
         print(colored("=", 'yellow'), end=" ")
@@ -40,21 +42,21 @@ def pprint(expr, pr=True):
     "3*diff((4*x)^2 + 1, x)",
 ])
 def test_basic_differentiation(expr):
-    pprint(parse(expr), False)
+    pprint(expr, False)
 
 @pytest.mark.parametrize('expr', cases + cases_extend)
 def test_more_differentiation(expr):
-    pprint(parse(('diff(' + expr + ', x)')), False)
+    pprint(('diff(' + expr + ', x)'), False)
 
 @pytest.mark.parametrize('expr', cases2 + cases2_extend)
 def test_moremore_differentiation(expr):
-    pprint(parse(('diff(' + expr + ', x)')), False)
+    pprint(('diff(' + expr + ', x)'), False)
 
 
 @pytest.mark.parametrize('expr', cases + cases_extend)
 def test_moremoremore_differentiation(expr):
-    pprint(parse(('diff(diff(' + expr + ', x), x)')), False)
+    pprint(('diff(diff(' + expr + ', x), x)'), False)
 
 @pytest.mark.parametrize('expr', cases2 + cases2_extend)
 def test_moremoremore_differentiation(expr):
-    pprint(parse(('diff(diff(' + expr + ', x), x)')), False)
\ No newline at end of file
+    pprint('diff(diff(' + expr + ', x), x)', False)
\ No newline at end of file