Merge pull request #816 from dmamelin/fix-ast-slice

fix ast slices

Author: craigbarratt

custom_components/pyscript/eval.py

@@ -1385,16 +1385,7 @@ async def recurse_assign(self, lhs, val):
                     val_idx += 1
         elif isinstance(lhs, ast.Subscript):
             var = await self.aeval(lhs.value)
-            if isinstance(lhs.slice, ast.Index):
-                ind = await self.aeval(lhs.slice.value)
-                var[ind] = val
-            elif isinstance(lhs.slice, ast.Slice):
-                lower = await self.aeval(lhs.slice.lower) if lhs.slice.lower else None
-                upper = await self.aeval(lhs.slice.upper) if lhs.slice.upper else None
-                step = await self.aeval(lhs.slice.step) if lhs.slice.step else None
-                var[slice(lower, upper, step)] = val
-            else:
-                var[await self.aeval(lhs.slice)] = val
+            var[await self.aeval(lhs.slice)] = val
         else:
             var_name = await self.aeval(lhs)
             if isinstance(var_name, EvalAttrSet):
@@ -1455,21 +1446,7 @@ async def ast_delete(self, arg):
         for arg1 in arg.targets:
             if isinstance(arg1, ast.Subscript):
                 var = await self.aeval(arg1.value)
-                if isinstance(arg1.slice, ast.Index):
-                    ind = await self.aeval(arg1.slice.value)
-                    for elt in ind if isinstance(ind, list) else [ind]:
-                        del var[elt]
-                elif isinstance(arg1.slice, ast.Slice):
-                    lower, upper, step = None, None, None
-                    if arg1.slice.lower:
-                        lower = await self.aeval(arg1.slice.lower)
-                    if arg1.slice.upper:
-                        upper = await self.aeval(arg1.slice.upper)
-                    if arg1.slice.step:
-                        step = await self.aeval(arg1.slice.step)
-                    del var[slice(lower, upper, step)]
-                else:
-                    del var[await self.aeval(arg1.slice)]
+                del var[await self.aeval(arg1.slice)]
             elif isinstance(arg1, ast.Name):
                 if self.curr_func and arg1.id in self.curr_func.global_names:
                     if arg1.id in self.global_sym_table:
@@ -1857,13 +1834,6 @@ async def ast_subscript(self, arg):
         """Evaluate subscript."""
         var = await self.aeval(arg.value)
         if isinstance(arg.ctx, ast.Load):
-            if isinstance(arg.slice, ast.Index):
-                return var[await self.aeval(arg.slice)]
-            if isinstance(arg.slice, ast.Slice):
-                lower = (await self.aeval(arg.slice.lower)) if arg.slice.lower else None
-                upper = (await self.aeval(arg.slice.upper)) if arg.slice.upper else None
-                step = (await self.aeval(arg.slice.step)) if arg.slice.step else None
-                return var[slice(lower, upper, step)]
             return var[await self.aeval(arg.slice)]
         return None
 
@@ -1873,7 +1843,10 @@ async def ast_index(self, arg):
 
     async def ast_slice(self, arg):
         """Evaluate slice."""
-        return await self.aeval(arg.value)
+        lower = (await self.aeval(arg.lower)) if arg.lower else None
+        upper = (await self.aeval(arg.upper)) if arg.upper else None
+        step = (await self.aeval(arg.step)) if arg.step else None
+        return slice(lower, upper, step)
 
     async def ast_call(self, arg):
         """Evaluate function call."""

tests/test_unit_eval.py

@@ -113,6 +113,8 @@
     ["[0, 1, 2, 3, 4, 5, 6, 7, 8][:4:]", [0, 1, 2, 3]],
     ["[0, 1, 2, 3, 4, 5, 6, 7, 8][::2]", [0, 2, 4, 6, 8]],
     ["[0, 1, 2, 3, 4, 5, 6, 7, 8][::]", [0, 1, 2, 3, 4, 5, 6, 7, 8]],
+    ["[0, 1, 2, 3, 4][4:1:-1]", [4, 3, 2]],
+    ["a = 1; b = 6; c = 2; [0, 1, 2, 3, 4, 5, 6][a:b:c]", [1, 3, 5]],
     ["z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[1:5:2] = [6, 8]; z", [0, 6, 2, 8, 4, 5, 6, 7, 8]],
     ["z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[1:5] = [10, 11]; z", [0, 10, 11, 5, 6, 7, 8]],
     ["z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[1::3] = [10, 11, 12]; z", [0, 10, 2, 3, 11, 5, 6, 12, 8]],
@@ -121,6 +123,10 @@
     ["z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[:6:2] = [10, 11, 12]; z", [10, 1, 11, 3, 12, 5, 6, 7, 8]],
     ["z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[:4:] = [10, 11, 12, 13]; z", [10, 11, 12, 13, 4, 5, 6, 7, 8]],
     ["z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[::2] = [10, 11, 12, 13, 14]; z", [10, 1, 11, 3, 12, 5, 13, 7, 14]],
+    ["x = [0, 1, 2, 3, 4]; x[1:4] = [9, 8]; x", [0, 9, 8, 4]],
+    ["x = [0, 1, 2, 3, 4, 5]; x[::2] = [9, 8, 7]; x", [9, 1, 8, 3, 7, 5]],
+    ["x = [0, 1, 2, 3, 4, 5]; del x[1:5:2]; x", [0, 2, 4, 5]],
+    ["x = [0, 1, 2, 3, 4]; del x[::-2]; x", [1, 3]],
     [
         "z = [0, 1, 2, 3, 4, 5, 6, 7, 8]; z[::] = [10, 11, 12, 13, 14, 15, 16, 17]; z",
         [10, 11, 12, 13, 14, 15, 16, 17],