Well, inputBody is only set to a non-null value if that is the case, no?

Do you mean the case is "If inputBody is body" ? No, it can be both inputBody is null and body is null.

Neither body nor inputBody can be a Request object. They are null or a body. So

inputBody is body and a Request object

always returns false.

But disturbed/locked also does a non-null check so that part is covered, no? (We could make step 38 step 39.0 I suppose and assert that input's body is non-null, but would that make it better?)

@yutakahirano
I missed. It should be
"If inputBody is body and input is a Request object, ..."

@annevk
Disturbed/locked checks Body mixin's body is non-null but doesn't check Body's non-null.

@yoichio I don't follow. A Request object's body is Body mixin's body. Body itself is a mixin that Request includes, it cannot be null.

Body itself is a mixin that Request includes, it cannot be null.

Yes.

I feel discussion is going wrong. Back to the original question:
if input is string and init["body"] doesn't exist, the 38th step is asking whether the input is disturbed or locked.
That's strange.

I see, so yeah, moving step 38 to 39.0 would be the right approach here as we need to know that body/inputBody are non-null.