EVOLUTION-MANAGER

Edit File: testServer.html

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<table width="100%" summary="page for testServer {shiny}"><tr><td>testServer {shiny}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Reactive testing for Shiny server functions and modules</h2>

<h3>Description</h3>

<p>A way to test the reactive interactions in Shiny applications. Reactive
interactions are defined in the server function of applications and in
modules.
</p>

<h3>Usage</h3>

<pre>
testServer(app = NULL, expr, args = list(), session = MockShinySession$new())
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>app</code></td>
<td>
<p>The path to an application or module to test. In addition to
paths, applications may be represented by any object suitable for coercion
to an <code>appObj</code> by <code><a href="shiny.appobj.html">as.shiny.appobj</a></code>. Application server functions must
include a <code>session</code> argument in order to be tested. If <code>app</code> is <code>NULL</code> or
not supplied, the nearest enclosing directory that is a Shiny app, starting
with the current directory, is used.</p>
</td></tr>
<tr valign="top"><td><code>expr</code></td>
<td>
<p>Test code containing expectations. The test expression will run
in the server function environment, meaning that the parameters of the
server function (e.g. <code>input</code>, <code>output</code>, and <code>session</code>) will be available
along with any other values created inside of the server function.</p>
</td></tr>
<tr valign="top"><td><code>args</code></td>
<td>
<p>Additional arguments to pass to the module function. If <code>app</code> is
a module, and no <code>id</code> argument is provided, one will be generated and
supplied automatically.</p>
</td></tr>
<tr valign="top"><td><code>session</code></td>
<td>
<p>The <code><a href="MockShinySession.html">MockShinySession</a></code> object to use as the <a href="domains.html">reactive domain</a>. The same session object is used as the domain both
during invocation of the server or module under test and during evaluation
of <code>expr</code>.</p>
</td></tr>
</table>

<h3>Examples</h3>

<pre>
server &lt;- function(id, multiplier = 2, prefix = "I am ") {
  moduleServer(id, function(input, output, session) {
    myreactive &lt;- reactive({
      input$x * multiplier
    })
    output$txt &lt;- renderText({
      paste0(prefix, myreactive())
    })
  })
}

testServer(server, args = list(multiplier = 2), {
  session$setInputs(x = 1)
  # You're also free to use third-party
  # testing packages like testthat:
  #   expect_equal(myreactive(), 2)
  stopifnot(myreactive() == 2)
  stopifnot(output$txt == "I am 2")

session$setInputs(x = 2)
  stopifnot(myreactive() == 4)
  stopifnot(output$txt == "I am 4")
  # Any additional arguments, below, are passed along to the module.
})
</pre>

<hr /><div style="text-align: center;">[Package <em>shiny</em> version 1.5.0 <a href="00Index.html">Index</a>]</div>
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