3.7+ "or" disambiguation and assert2 handling

test/simple_source/bug37/01_assert2.py

@@ -6,3 +6,13 @@ def test_assert2(c):
         raise SyntaxError('Oops')
 
 test_assert2(5)
+
+# Bug is handling "assert" and confusing it with "or".
+# It is important that the assert be at the end of the loop.
+for x in (2, 4, 6):
+    assert x == x
+
+# Bug in 3.7 was not having a rule for 2-arg assert.
+# 2-arg assert code doesn't match "if not ... raise "
+for x in (1, 3, 5):
+    assert x == x, "foo"

uncompyle6/parsers/parse37.py

@@ -760,6 +760,10 @@ class Python37Parser(Python37BaseParser):
         stmt ::= classdefdeco
         classdefdeco ::= classdefdeco1 store
 
+        # In 3.7 there are some LOAD_GLOBALs we don't convert to LOAD_ASSERT
+        stmt    ::= assert2
+        assert2 ::= expr jmp_true LOAD_GLOBAL expr CALL_FUNCTION_1 RAISE_VARARGS_1
+
         expr    ::= LOAD_ASSERT
 
         ifstmt ::= testexpr _ifstmts_jump

uncompyle6/parsers/reducecheck/or_check.py

@@ -3,6 +3,23 @@
 
 def or_check(self, lhs, n, rule, ast, tokens, first, last):
     if rule == ("or", ("expr", "jmp_true", "expr")):
+        if tokens[last] in (
+                "LOAD_ASSERT",
+                "RAISE_VARARGS_1",
+        ):
+            return True
+
+        # The following test is be the most accurate. It prevents "or" from being
+        # mistake for part of an "assert".
+        # There one might conceivably be "expr or AssertionError" code, but the
+        # likelihood of that is vanishingly small.
+        # The below then is useful until we get better control-flow analysis.
+        # Note it is too hard in the scanner right nowto turn the LOAD_GLOBAL into
+        # int LOAD_ASSERT, however in 3.9ish code generation does this by default.
+        load_global = tokens[last-1]
+        if load_global == "LOAD_GLOBAL" and load_global.attr == "AssertionError":
+            return True
+
         jmp_true_target = ast[1][0].attr
         jmp_false = tokens[last]
         # If the jmp is backwards
@@ -13,9 +30,5 @@ def or_check(self, lhs, n, rule, ast, tokens, first, last):
                 jmp_false = tokens[last+1]
             return not (jmp_true_target == jmp_false.off2int() or
                         jmp_true_target < tokens[first].off2int())
-        return tokens[last] in (
-            "LOAD_ASSERT",
-            "RAISE_VARARGS_1",
-            )
 
     return False

uncompyle6/semantics/customize.py

@@ -48,8 +48,8 @@ def customize_for_version(self, is_pypy, version):
         #######################
         TABLE_DIRECT.update({
             # "assert" and "assert_expr" are added via transform rules.
-            "assert": ("%|assert %c\n", (0, "assert_expr")),
+            "assert": ("%|assert %c\n", 0),
-            "assert2": ("%|assert %c, %c\n", (0, "assert_expr"), 3),
+            "assert2": ("%|assert %c, %c\n", 0, 3),
 
             # Created only via transformation
             "assertnot": ("%|assert not %p\n", (0, PRECEDENCE['unary_not'])),