MDL-79938 Behat: Add steps to support multiple tabs

admin/tool/behat/tests/behat/tabs.feature

@@ -0,0 +1,34 @@
+@tool_behat
+Feature: Confirm that we can open multiple browser tabs
+  In order to use multiple browser tabs
+  As a test writer
+  I need the relevant Behat steps to work
+
+  @javascript @_switch_window
+  Scenario: Open multiple browser tabs
+    Given the following "courses" exist:
+      | fullname | shortname |
+      | Course 1 | C1        |
+      | Course 2 | C2        |
+      | Course 3 | C3        |
+    And I am on the "C1" "Course" page logged in as "admin"
+
+    # Open a new tab on the same page.
+    When I open a tab named "CourseViewer1" on the current page
+    And I should see "Course 1" in the "h1" "css_element"
+    And I am on the "C2" "Course" page
+
+    # Open new tab for specified page with identifier.
+    And I open a tab named "CourseViewer2" on the "C3" "Course" page
+
+    # And for a specified page without identifier.
+    And I open a tab named "CourseViewer4" on the "My courses" page
+
+    # Switch between all the tabs and confirm their different contents.
+    Then I should see "No courses"
+    And I switch to "CourseViewer2" tab
+    And I should see "Course 3" in the "h1" "css_element"
+    And I switch to "CourseViewer1" tab
+    And I should see "Course 2" in the "h1" "css_element"
+    And I switch to the main tab
+    And I should see "Course 1" in the "h1" "css_element"

lib/tests/behat/behat_general.php

@@ -200,7 +200,7 @@ public function switch_to_the_main_frame() {
     /**
      * Switches to the specified window. Useful when interacting with popup windows.
      *
-     * @Given /^I switch to "(?P<window_name_string>(?:[^"]|\\")*)" window$/
+     * @Given /^I switch to "(?P<window_name_string>(?:[^"]|\\")*)" (window|tab)$/
      * @param string $windowname
      */
     public function switch_to_window($windowname) {
@@ -232,7 +232,7 @@ public function switch_to_second_window() {
     /**
      * Switches to the main Moodle window. Useful when you finish interacting with popup windows.
      *
-     * @Given /^I switch to the main window$/
+     * @Given /^I switch to the main (window|tab)$/
      */
     public function switch_to_the_main_window() {
         $this->switch_to_window(self::MAIN_WINDOW_NAME);

lib/tests/behat/behat_navigation.php

@@ -909,6 +909,63 @@ protected function resolve_core_page_instance_url(string $type, string $identifi
         throw new Exception('Unrecognised core page type "' . $type . '."');
     }
 
+    /**
+     * Opens a new tab with given name on the same URL as current page and switches to it.
+     *
+     * @param string $name Tab name that can be used for switching later (no whitespace)
+     * @When /^I open a tab named "(?<name>[^"]*)" on the current page$/
+     */
+    public function i_open_a_tab_on_the_current_page(string $name): void {
+        $this->open_tab($name, 'location.href');
+    }
+
+    /**
+     * Opens a new tab with given name on specified page, and switches to it.
+     *
+     * @param string $name Tab name that can be used for switching later (no whitespace)
+     * @param string $page Page name
+     * @When /^I open a tab named "(?<name>[^"]*)" on the "(?<page>[^"]*)" page$/
+     */
+    public function i_open_a_tab_on_the_page(string $name, string $page): void {
+        if ($page === 'current') {
+            $jstarget = 'location.href';
+        } else {
+            $jstarget = '"' . addslashes_js($this->resolve_page_helper($page)->out(false)) . '"';
+        }
+        $this->open_tab($name, $jstarget);
+    }
+
+    /**
+     * Opens a new tab with given name (on specified page), and switches to it.
+     *
+     * @param string $name Tab name that can be used for switching later (no whitespace)
+     * @param string $identifier Page identifier
+     * @param string $page Page type
+     * @When /^I open a tab named "(?<name>[^"]*)" on the "(?<identifier>[^"]*)" "(?<page>[^"]*)" page$/
+     */
+    public function i_open_a_tab_on_the_page_instance(string $name, string $identifier, string $page): void {
+        $this->open_tab($name, '"' . addslashes_js(
+            $this->resolve_page_instance_helper($identifier, $page)->out(false)) . '"');
+    }
+
+    /**
+     * Opens a new tab at the given target URL.
+     *
+     * @param string $name Name for tab
+     * @param string $jstarget Target in JavaScript syntax, i.e. if a string, must be quoted
+     */
+    protected function open_tab(string $name, string $jstarget): void {
+        // Tab names aren't allowed spaces, and our JavaScript below doesn't do any escaping.
+        if (clean_param($name, PARAM_ALPHANUMEXT) !== $name) {
+            throw new Exception('Tab name may not contain whitespace or special characters: "' . $name . '"');
+        }
+
+        // Normally you can't open a tab unless in response to a user action, but presumably Behat
+        // is exempt from this restriction, because it works to just open it directly.
+        $this->execute_script('window.open(' . $jstarget . ', "' . $name . '");');
+        $this->execute('behat_general::switch_to_window', [$name]);
+    }
+
     /**
      * Opens the course homepage. (Consider using 'I am on the "shortname" "Course" page' step instead.)
      *