`selectedpoints` does not function properly when a vector is passed using `plotlyProxy` & `"restyle"`.

Bug/Unexpected Behavior

When updating a scatter plot's selectedpoints in a Shiny server using "restyle" on a plotlyProxy, single value vectors don't update the graph. E.g., passing c(1) to selectedpoints won't update the graph.

However, if we duplicate this value, e.g., c(1, 1) and pass it to selectedpoints, the 1 point will be selected.

Reproducible example:

# selected points single value incorrect behavior
library(shiny)

ui <- fluidPage(fluidRow(plotly::plotlyOutput("graph"),
                         DT::DTOutput("table")))

server <- function(input, output, session) {
  output$table <- DT::renderDT({
    cars
  })
  
  output$graph <- plotly::renderPlotly({
    plotly::plot_ly(
      cars,
      x = ~ speed,
      y = ~ dist,
      selected = list(marker = list(color = "red")),
      type = "scatter",
      mode = "markers",
      source = "graph"
    ) %>%
      plotly::layout(dragmode = "select",
                     clickmode = "event+select") %>%
      plotly::event_register("plotly_selected")
  })
  
  plot_proxy <- plotly::plotlyProxy("graph")
  table_proxy <- DT::dataTableProxy("table")
  
  selected <-
    reactive({
      plotly::event_data("plotly_selected", source = "graph")
    })
  
  observeEvent(selected(), {
    selected <- selected()$pointNumber + 1
    table_proxy %>% DT::selectRows(selected)
  })
  
  observeEvent(input$table_cell_clicked, {
    selected_rows <- input$table_rows_selected - 1

   #### comment this conditional to see the bug ####
    if (length(selected_rows) == 1) {
      selected_rows <- rep(selected_rows, 2)
    }
   #### end comment this conditional to see the bug ####

   plotly::plotlyProxyInvoke(
      plotly::plotlyProxy("graph", session),
      "restyle",
      list(selectedpoints = list(selected_rows)),
      0
    )
  })
  
}

shinyApp(ui, server)

まず、提供された再現可能な R Shiny の例を実行し、c(1) を含む selected_rows を使った plotlyProxyInvoke と c(1, 1) を比較します。plotlyProxy の "restyle" 呼び出しを通じた selectedpoints の更新を追跡します。単一値のベクトルで重複なく点が選択されれば完了です。