🚨 added test

tests/integration/callbacks/test_no_update.py

@@ -1,4 +1,5 @@
 from selenium.webdriver.support.select import Select
+import time
 
 app = """
 library(dash)
@@ -16,19 +17,49 @@
       list(label = "Do nothing", value = "nothing")
     ),
     id = "color-selector"),
+    htmlButton(children = "Select all the colors!",
+               id = "multi-selector"
+               ),
     htmlDiv(id='message-box',
-            children='Please select a colour choice from the dropdown menu.')
+            children='Please select a color choice from the dropdown menu.'),
+    htmlDiv(id='message-box2',
+            children=' ')
   )
   )
 )
 
+app$callback(output=list(id='message-box2', property='children'),
+             params=list(
+               input(id='multi-selector', property='n_clicks')),
+             function(n_clicks)
+             {
+               # if button has been clicked, n_clicks is numeric()
+               # on first launch of callback at layout initialization,
+               # value of n_clicks will be list(NULL), which is not
+               # comparable using >, < or =; hence the is.numeric()
+               # check
+               if (is.numeric(n_clicks) && n_clicks >= 1)
+               {
+                 # return a vector to ensure that the check for
+                 # class(x) == "no_update" isn't made for objects
+                 # where length(x) > 1
+                 return(c("Multiple color values: ", 
+                          "#FF0000, ", 
+                          "#00FF00, ", 
+                          "#0000FF ", 
+                          "returned!")
+                        )
+               }
+             }
+)
+
 app$callback(output=list(id='message-box', property='children'),
              params=list(
                input(id='color-selector', property='value')),
              function(color)
              {
                if (color %in% c("#FF0000", "#00FF00", "#0000FF")) {
-                 msg <- sprintf("The hexadecimal representation of your last chosen colour is %s",
+                 msg <- sprintf("The hexadecimal representation of your last chosen color is %s",
                                 color)
                  return(msg)
                } else {
@@ -37,27 +68,36 @@
              }
 )
 
-app$run_server()
+app$run_server(component_cache_max_age=0)
 """
 
 
 def test_rsnu001_no_update(dashr):
     dashr.start_server(app)
     dashr.find_element("#color-selector").click()
     dashr.find_elements("div.VirtualizedSelectOption")[0].click()
-    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen colour is #FF0000"
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen color is #FF0000"
     dashr.find_element("#color-selector").click()
     dashr.find_elements("div.VirtualizedSelectOption")[3].click()
-    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen colour is #FF0000"
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen color is #FF0000"
     dashr.find_element("#color-selector").click()
     dashr.find_elements("div.VirtualizedSelectOption")[1].click()
-    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen colour is #00FF00"
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen color is #00FF00"
     dashr.find_element("#color-selector").click()
     dashr.find_elements("div.VirtualizedSelectOption")[3].click()
-    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen colour is #00FF00"
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen color is #00FF00"
     dashr.find_element("#color-selector").click()
     dashr.find_elements("div.VirtualizedSelectOption")[2].click()
-    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen colour is #0000FF"
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen color is #0000FF"
     dashr.find_element("#color-selector").click()
     dashr.find_elements("div.VirtualizedSelectOption")[3].click()
-    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen colour is #0000FF"
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "The hexadecimal representation of your last chosen color is #0000FF"
+    dashr.find_element("#multi-selector").click()
+    time.sleep(1)
+    assert dashr.find_element("#message-box").text == "Multiple color values: #FF0000, #00FF00, #0000FF returned!"