[SR-11497] Duplicated spacer leads to 'Ambiguous reference to member 'buildBlock()'

[swift-ci]

Previous ID	SR-11497
Radar	rdar://problem/55560957
Original Reporter	stevex (JIRA User)
Type	Bug

Attachment: Download

Additional Detail from JIRA

| | | |------------------|-----------------| |Votes | 0 | |Component/s | Compiler | |Labels | Bug, FunctionBuilder | |Assignee | None | |Priority | Medium | md5: 5a96ef644edd478a2faa4bdea83ca57c

Issue Description:

In a nutshell:

struct ContentView : View {
    var body: some View {
        VStack {
            Spacer()
            HStack {
                Spacer()  // comment out this line, and the error goes away
                Spacer()
                Text("X")
                Spacer()
                Text("X")
                Spacer()
                Text("X")
                Spacer()
                Text("X")
                Spacer()
                Spacer()
            }
            Spacer()
        }
    }
}

Attempting to use spacers in an HStack as a layout shortcut .. having two Spacer at the start produces the error 'Ambiguous reference to member buildBlock()'. Comment out the first line and it builds successfully.

Sample project attached.

[belkadan]

@rjmccall, do you have a dup for this?

[belkadan]

@swift-ci create

[rjmccall]

No, I don't think so.

This is just a specific bad diagnostic for having more elements than the function builder allows. (Allowing arbitrary element counts is also a problem, of course.)