Shiny can create HTML with duplicated IDs because of shinyInputLabel's automatic ID

[daattali]

In this line https://github.com/rstudio/shiny/blob/b52b9e4520ad8d1e976299d5dec5e4ba3096bd04/R/input-utils.R#L7 an ID attribute is generated automatically. This results in a very real possibility of ending up with duplicate IDs.

Example:

h2(
  id = "name-label",
  "Student name",
  textInput("name", "First name"),
  textInput("lname", "Last name")
)

This generates the following HTML, which contains two "name-label" IDs. Perhaps duplicating IDs in label tags is considered to be good practice, but as far as I know assigning automatic IDs should be a big no-no because of this issue

<h2 id="name-label">
  Student name
  <div class="form-group shiny-input-container">
    <label class="control-label" id="name-label" for="name">First name</label>
    <input id="name" type="text" class="form-control" value=""/>
  </div>
  <div class="form-group shiny-input-container">
    <label class="control-label" id="lname-label" for="lname">Last name</label>
    <input id="lname" type="text" class="form-control" value=""/>
  </div>
</h2>