Fixing description of [[thisMode]] internal slot of Function Object.

[ENvironmentSet]

in current, specification explain [[thisMode]] of Function Object as blow.

Defines how this references are interpreted within the formal parameters
and code body of the function. lexical means that this refers to the this
value of a lexically enclosing function. strict means that the this value is used
exactly as provided by an invocation of the function. global means that a this
value of undefined is interpreted as a reference to the global object.

and I think, this line missed some action about how global this mode works.

global means that a this
value of undefined is interpreted as a reference to the global object.

because, In OrdinaryCallBindThis abstract operation that used to bind this value into function environment record. It interpret null as reference to global object like undefined.

So, In my opinion, changing that line to blow will make more clear specification.

global means that a this
value of undefined or null is interpreted as a reference to the global object.

[ljharb]

Indeed, in step 6.a of https://tc39.github.io/ecma262/#sec-ordinarycallbindthis it checks undefined or null; which suggests that the text in https://tc39.github.io/ecma262/#table-27 should be changed from "undefined" to "undefined or null".

[ljharb]

Indeed, in step 6.a of https://tc39.github.io/ecma262/#sec-ordinarycallbindthis it checks undefined or null; which suggests that the text in https://tc39.github.io/ecma262/#table-27 should be changed from "undefined" to "undefined or null".

[ENvironmentSet]

and, another one about this.

in step 6.b.i of OrdinaryCallBindThis it convert primitive value to Object. we may add information about this too.

[ENvironmentSet]

and, another one about this.

in step 6.b.i of OrdinaryCallBindThis it convert primitive value to Object. we may add information about this too.