Use yield from where possible

parso/python/errors.py

@@ -173,13 +173,11 @@ def _iter_definition_exprs_from_lists(exprlist):
             if child.children[0] == '(':
                 testlist_comp = child.children[1]
                 if testlist_comp.type == 'testlist_comp':
-                    for expr in _iter_definition_exprs_from_lists(testlist_comp):
+                    yield from _iter_definition_exprs_from_lists(testlist_comp)
-                        yield expr
                     return
                 else:
                     # It's a paren that doesn't do anything, like 1 + (1)
-                    for c in check_expr(testlist_comp):
+                    yield from check_expr(testlist_comp)
-                        yield c
                     return
             elif child.children[0] == '[':
                 yield testlist_comp
@@ -188,11 +186,9 @@ def _iter_definition_exprs_from_lists(exprlist):
 
     if exprlist.type in _STAR_EXPR_PARENTS:
         for child in exprlist.children[::2]:
-            for c in check_expr(child):  # Python 2 sucks
+            yield from check_expr(child)
-                yield c
     else:
-        for c in check_expr(exprlist):  # Python 2 sucks
+        yield from check_expr(exprlist)
-            yield c
 
 
 def _get_expr_stmt_definition_exprs(expr_stmt):

parso/python/tokenize.py

@@ -528,14 +528,12 @@ def tokenize_lines(lines, version_info, start_pos=(1, 0), indents=None, is_first
                     if indent_start > indents[-1]:
                         yield PythonToken(INDENT, '', spos, '')
                         indents.append(indent_start)
-                    for t in dedent_if_necessary(indent_start):
+                    yield from dedent_if_necessary(indent_start)
-                        yield t
 
             if not pseudomatch:  # scan for tokens
                 match = whitespace.match(line, pos)
                 if new_line and paren_level == 0 and not fstring_stack:
-                    for t in dedent_if_necessary(match.end()):
+                    yield from dedent_if_necessary(match.end())
-                        yield t
                 pos = match.end()
                 new_line = False
                 yield PythonToken(
@@ -556,13 +554,11 @@ def tokenize_lines(lines, version_info, start_pos=(1, 0), indents=None, is_first
                     # We only want to dedent if the token is on a new line.
                     m = re.match(r'[ \f\t]*$', line[:start])
                     if m is not None:
-                        for t in dedent_if_necessary(m.end()):
+                        yield from dedent_if_necessary(m.end())
-                            yield t
                 if is_identifier(token):
                     yield PythonToken(NAME, token, spos, prefix)
                 else:
-                    for t in _split_illegal_unicode_name(token, spos, prefix):
+                    yield from _split_illegal_unicode_name(token, spos, prefix)
-                        yield t  # yield from Python 2
             elif initial in '\r\n':
                 if any(not f.allow_multiline() for f in fstring_stack):
                     # Would use fstring_stack.clear, but that's not available

parso/python/tree.py

@@ -363,8 +363,7 @@ class Scope(PythonBaseNode, DocstringMixin):
                 if element.type in names:
                     yield element
                 if element.type in _FUNC_CONTAINERS:
-                    for e in scan(element.children):
+                    yield from scan(element.children)
-                        yield e
 
         return scan(self.children)
 
@@ -615,8 +614,7 @@ class Function(ClassOrFunc):
                         else:
                             yield element
                 else:
-                    for result in scan(nested_children):
+                    yield from scan(nested_children)
-                        yield result
 
         return scan(self.children)
 
@@ -630,8 +628,7 @@ class Function(ClassOrFunc):
                         or element.type == 'keyword' and element.value == 'return':
                     yield element
                 if element.type in _RETURN_STMT_CONTAINERS:
-                    for e in scan(element.children):
+                    yield from scan(element.children)
-                        yield e
 
         return scan(self.children)
 
@@ -645,8 +642,7 @@ class Function(ClassOrFunc):
                         or element.type == 'keyword' and element.value == 'raise':
                     yield element
                 if element.type in _RETURN_STMT_CONTAINERS:
-                    for e in scan(element.children):
+                    yield from scan(element.children)
-                        yield e
 
         return scan(self.children)
 
@@ -1098,8 +1094,7 @@ class ExprStmt(PythonBaseNode, DocstringMixin):
             first = first.children[2]
         yield first
 
-        for operator in self.children[3::2]:
+        yield from self.children[3::2]
-            yield operator
 
 
 class Param(PythonBaseNode):