parsing issue affecting content assist

Given the following grammar definition

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.common.Terminals hidden(SL_COMMENT, WS)

generate myDsl "http://www.xtext.org/example/mydsl/MyDsl"

World:
    {World}
    fooBars+=FooBar*
    ;

FooBar:
    Foo|Bar
;

Foo:
    "Foo" name=ID '{'
      fooDef=FooDef
    '}'
;

FooDef:
    "FooDef" name=ID '{'
    "barRef" '=' barRef=[Bar|ID] ';'
    '}';

Bar:
    "Bar" name=ID '{'
    '}';

The following code works just fine:

Bar bar1{}

Foo foo1
{
	FooDef fd
	{
		barRef=bar1;
	}
}

Reversing the definitions of bar1 and foo1 only seems like working fine (it validates):

Foo foo1
{
	FooDef fd
	{
		barRef=bar1;
	}
}

Bar bar1{}

but actually, if you try to use the content assist after bar Ref= you will see it doesn't work.

The internal parser (antlr?) is confused because of the closing curly bracket of foo1 so everything after the foo1 definition is not parsed anymore.

The workaround is:

FooDef:
    "FooDef" name=ID '{'
    	x=X
    '}';
    
X:
	"barRef" '=' barRef=[Bar|ID] ';'
;   

Use the supplied grammar and document order as the reproducer, then inspect Xtext's parser and content-assist handling for the cross-reference after FooDef. Verify the case where Foo appears before Bar and content assist is invoked after barRef=; done means bar1 is offered and the later Bar definition remains parsed correctly.