奇怪的符号“”出现在闪亮的

Question

以下是输出的屏幕截图：

问题似乎与$setLib()功能有关。根据给定的目录，它给出了相应的字符串输出。提供正确的目录会生成符号。

例如，提供URL会生成此输出而不显示图表：
代码 - sankeyPlot$setLib("https://github.com/timelyportfolio/rCharts_d3_sankey")
输出 - https://github.com/timelyportfolio/rCharts_d3_sankey/layouts/chart.html

以下是复制错误的示例代码：

require(rCharts)
require(rjson)
require(shiny)

links <- matrix(unlist(
  rjson::fromJSON(
    file = "http://bost.ocks.org/mike/sankey/energy.json"
  )$links
),ncol = 3, byrow = TRUE)
nodes <- unlist(
  rjson::fromJSON(
    file = "http://bost.ocks.org/mike/sankey/energy.json"
  )$nodes
)
#convert to data.frame so souce and target can be character and value numeric
links <- data.frame(links)
colnames(links) <- c("source", "target", "value")
links$source <- sapply(links$source, FUN = function(x) {return(as.character(nodes[x+1]))}) #x+1 since js starts at 0
links$target <- sapply(links$target, FUN = function(x) {return(nodes[x+1])}) #x+1 since js starts at 0


server <- function(input, output) {
  output$sankey <-  renderChart2({

    sankeyPlot <- rCharts$new()
    sankeyPlot$setLib("./d3_sankey")

    sankeyPlot$set(
      data = links,

      nodeWidth = 15,
      nodePadding = 15,
      layout = 30

    )
    return(sankeyPlot)
  })
}

ui <- fluidPage(
  showOutput('sankey', 'd3_sankey')
)

shinyApp(ui = ui, server = server)