No warning or error if an invalid target attribute is set to None

[jmillikin-stripe]

Description of the problem / feature request:

Given the following BUILD file:

cc_binary(
    name = "hello",            
    srcs = ["hello.c"],        
    no_such_attribute = None,
)

I would expect some sort of error to be printed. There is an error if the invalid attribute is set to some non-None value (0, False, whatever) but None is just silently ignored.

A warning would also be acceptable (backwards compatibility and all), maybe with a flag to make it a hard error (defaulting to true in the next breaking release).

This behavior happens for both built-in and Starlark-defined rules.

What operating system are you running Bazel on?

macOS

What's the output of bazel info release?

release 2.2.0

[alandonovan]

Dup of Google-internal issue: b/122552411.

[jin]

Is this still a P1 bug?

[brandjon]

This is certainly surprising, and should be an error for non-existent attributes.

Should None be a valid value for attributes that do exist though? For instance, I could imagine it having the same effect as omitting an optional attribute of Label type. Indeed, this might be necessary in order to support feeding the output of native.existing_rule back into a target definition. It'd presumably still be an error for mandatory attributes, and perhaps list-typed attributes that can use [] as the zero value.

[comius]

Wait what? :)

[iancha1992]

A fix for this issue has been included in Bazel 6.4.0 RC1. Please test out the release candidate and report any issues as soon as possible. Thanks!