yield bang after shorter if/then inside Elmish expression

[nojaf]

Issue created from fantomas-online

Code

let lessonsForm (f:ValidatedForm<Request.CreateLessons>) dispatch =
    
    Html.div [
        Bulma.field.div [
            Bulma.fieldBody [
                Bulma.button.button [
                    color.isPrimary
                    prop.text "Přidat lekce"
                    if f.IsLoading then yield! [ button.isLoading; prop.disabled true ]
                    prop.onClick (fun _ -> CreateLessons |> dispatch)
                ]
            ]
        ]
    ]

Error

Fantomas was able to format the code but the result appears to be invalid F# code.
Please open an issue.

Formatted result:

let lessonsForm (f: ValidatedForm<Request.CreateLessons>) dispatch =

    Html.div [ Bulma.field.div [ Bulma.fieldBody [ Bulma.button.button [ color.isPrimary
                                                                         prop.text "Přidat lekce"
                                                                         if f.IsLoading
                                                                         then yield!
                                                                             [ button.isLoading; prop.disabled true ]
                                                                         prop.onClick (fun _ ->
                                                                             CreateLessons |> dispatch) ] ] ] ]

Problem description

Please describe here fantomas problem you encountered.

Extra information

• The formatted result breaks by code.
• The formatted result gives compiler warnings.
• I or my company would be willing to help fix this.

Options

Fantomas Master at 10/2/2020

Default Fantomas configuration