stdlib/3/ast: add visit_* methods to NodeVisitor (#3796)

NodeVisitor recurses over an AST tree. When encountering a node, it
checks if a method called `visit_{node.__class__.__name__}` exists, and
calls it if so, otherwise calls the generic visitor.

Add the possible methods to NodeVisitor. This is not exactly correct,
since the methods don't *actually* exist on NodeVisitor, e.g.
`NodeVisitor().visit_Module(...)` doesn't work. But it's nice for
subclasses to know which methods they can override and which type they
should have.

tests/stubtest_whitelists/py36.txt

@@ -1,3 +1,7 @@
+ast.NodeVisitor.visit_AnnAssign
+ast.NodeVisitor.visit_Constant
+ast.NodeVisitor.visit_FormattedValue
+ast.NodeVisitor.visit_JoinedStr
 asyncio.Future.__init__
 asyncio.Task._wakeup
 asyncio.constants.SENDFILE_FALLBACK_READBUFFER_SIZE

tests/stubtest_whitelists/py37.txt

@@ -2,6 +2,10 @@ _bisect.bisect
 _bisect.insort
 _tracemalloc._get_object_traceback
 _tracemalloc.start
+ast.NodeVisitor.visit_AnnAssign
+ast.NodeVisitor.visit_Constant
+ast.NodeVisitor.visit_FormattedValue
+ast.NodeVisitor.visit_JoinedStr
 asyncio.AbstractEventLoop.create_unix_server
 asyncio.AbstractEventLoop.sock_sendfile
 asyncio.Future.__init__

tests/stubtest_whitelists/py38.txt

@@ -5,6 +5,10 @@ _thread._ExceptHookArgs
 _tracemalloc._get_object_traceback
 _tracemalloc.start
 _weakref.getweakrefcount
+ast.NodeVisitor.visit_AnnAssign
+ast.NodeVisitor.visit_FormattedValue
+ast.NodeVisitor.visit_JoinedStr
+ast.NodeVisitor.visit_NamedExpr
 asyncio.AbstractEventLoop.create_unix_server
 asyncio.AbstractEventLoop.sock_sendfile
 asyncio.Future.__init__

tests/stubtest_whitelists/py3_common.txt

@@ -15,6 +15,106 @@ abc.abstractstaticmethod
 aifc.open
 aifc.openfp
 argparse.Namespace.__getattr__
+ast.NodeVisitor.visit_Add
+ast.NodeVisitor.visit_And
+ast.NodeVisitor.visit_Assert
+ast.NodeVisitor.visit_Assign
+ast.NodeVisitor.visit_AsyncFor
+ast.NodeVisitor.visit_AsyncFunctionDef
+ast.NodeVisitor.visit_AsyncWith
+ast.NodeVisitor.visit_Attribute
+ast.NodeVisitor.visit_AugAssign
+ast.NodeVisitor.visit_AugLoad
+ast.NodeVisitor.visit_AugStore
+ast.NodeVisitor.visit_Await
+ast.NodeVisitor.visit_BinOp
+ast.NodeVisitor.visit_BitAnd
+ast.NodeVisitor.visit_BitOr
+ast.NodeVisitor.visit_BitXor
+ast.NodeVisitor.visit_BoolOp
+ast.NodeVisitor.visit_Break
+ast.NodeVisitor.visit_Bytes
+ast.NodeVisitor.visit_Call
+ast.NodeVisitor.visit_ClassDef
+ast.NodeVisitor.visit_Compare
+ast.NodeVisitor.visit_Continue
+ast.NodeVisitor.visit_Del
+ast.NodeVisitor.visit_Delete
+ast.NodeVisitor.visit_Dict
+ast.NodeVisitor.visit_DictComp
+ast.NodeVisitor.visit_Div
+ast.NodeVisitor.visit_Ellipsis
+ast.NodeVisitor.visit_Eq
+ast.NodeVisitor.visit_ExceptHandler
+ast.NodeVisitor.visit_Expr
+ast.NodeVisitor.visit_Expression
+ast.NodeVisitor.visit_ExtSlice
+ast.NodeVisitor.visit_FloorDiv
+ast.NodeVisitor.visit_For
+ast.NodeVisitor.visit_FunctionDef
+ast.NodeVisitor.visit_GeneratorExp
+ast.NodeVisitor.visit_Global
+ast.NodeVisitor.visit_Gt
+ast.NodeVisitor.visit_GtE
+ast.NodeVisitor.visit_If
+ast.NodeVisitor.visit_IfExp
+ast.NodeVisitor.visit_Import
+ast.NodeVisitor.visit_ImportFrom
+ast.NodeVisitor.visit_In
+ast.NodeVisitor.visit_Index
+ast.NodeVisitor.visit_Interactive
+ast.NodeVisitor.visit_Invert
+ast.NodeVisitor.visit_Is
+ast.NodeVisitor.visit_IsNot
+ast.NodeVisitor.visit_LShift
+ast.NodeVisitor.visit_Lambda
+ast.NodeVisitor.visit_List
+ast.NodeVisitor.visit_ListComp
+ast.NodeVisitor.visit_Load
+ast.NodeVisitor.visit_Lt
+ast.NodeVisitor.visit_LtE
+ast.NodeVisitor.visit_MatMult
+ast.NodeVisitor.visit_Mod
+ast.NodeVisitor.visit_Module
+ast.NodeVisitor.visit_Mult
+ast.NodeVisitor.visit_Name
+ast.NodeVisitor.visit_NameConstant
+ast.NodeVisitor.visit_Nonlocal
+ast.NodeVisitor.visit_Not
+ast.NodeVisitor.visit_NotEq
+ast.NodeVisitor.visit_NotIn
+ast.NodeVisitor.visit_Num
+ast.NodeVisitor.visit_Or
+ast.NodeVisitor.visit_Param
+ast.NodeVisitor.visit_Pass
+ast.NodeVisitor.visit_Pow
+ast.NodeVisitor.visit_RShift
+ast.NodeVisitor.visit_Raise
+ast.NodeVisitor.visit_Return
+ast.NodeVisitor.visit_Set
+ast.NodeVisitor.visit_SetComp
+ast.NodeVisitor.visit_Slice
+ast.NodeVisitor.visit_Starred
+ast.NodeVisitor.visit_Store
+ast.NodeVisitor.visit_Str
+ast.NodeVisitor.visit_Sub
+ast.NodeVisitor.visit_Subscript
+ast.NodeVisitor.visit_Suite
+ast.NodeVisitor.visit_Try
+ast.NodeVisitor.visit_Tuple
+ast.NodeVisitor.visit_UAdd
+ast.NodeVisitor.visit_USub
+ast.NodeVisitor.visit_UnaryOp
+ast.NodeVisitor.visit_While
+ast.NodeVisitor.visit_With
+ast.NodeVisitor.visit_Yield
+ast.NodeVisitor.visit_YieldFrom
+ast.NodeVisitor.visit_alias
+ast.NodeVisitor.visit_arg
+ast.NodeVisitor.visit_arguments
+ast.NodeVisitor.visit_comprehension
+ast.NodeVisitor.visit_keyword
+ast.NodeVisitor.visit_withitem
 asyncio.AbstractEventLoop.connect_accepted_socket
 asyncio.AbstractEventLoop.create_unix_connection
 asyncio.BaseChildWatcher