focus workspace: consider workspace_auto_back_and_forth

Additionally, adds some tests for the command.

Fixes #5744

release-notes/bugfixes/1-workspace_auto_back_and_forth-focus-workspace

@@ -0,0 +1 @@
+consider workspace_auto_back_and_forth in focus workspace

src/commands.c

@@ -1493,7 +1493,7 @@ void cmd_focus(I3_CMD, bool focus_workspace) {
             /* Show the workspace of the matched container, without necessarily
              * focusing it. */
             LOG("focusing workspace %p / %s - %p / %s\n", current->con, current->con->name, ws, ws->name);
-            workspace_show(ws);
+            workspace_show(maybe_auto_back_and_forth_workspace(ws));
         } else {
             LOG("focusing %p / %s\n", current->con, current->con->name);
             con_activate_unblock(current->con);

testcases/t/550-focus-workspace.t

@@ -0,0 +1,89 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • https://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • https://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • https://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • https://i3wm.org/downloads/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Test the 'focus workspace' command
+use i3test i3_autostart => 0;
+
+my $config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+EOT
+
+my $pid = launch_with_config($config);
+
+sub switch_and_check {
+    my ($cmd, $ws, $msg) = @_;
+    cmd $cmd;
+    is(focused_ws, $ws, "$msg: workspace '$ws' focused");
+}
+
+
+cmd 'workspace 1';
+my $win1 = open_window(wm_class => 'win1');
+switch_and_check('nop', '1', 'sanity check');
+
+cmd 'workspace "other workspace"';
+my $win2 = open_window(wm_class => 'win2');
+switch_and_check('nop', 'other workspace', 'sanity check');
+
+switch_and_check('[class=win1] focus workspace', '1', 'class criterion');
+switch_and_check('[class=win2] focus workspace', 'other workspace', 'class criterion');
+switch_and_check('[class=win2] focus workspace', 'other workspace', 'repeat class criterion');
+
+switch_and_check("[id=$win1->{id}] focus workspace", '1', 'window id criterion');
+switch_and_check("[id=$win1->{id}] focus workspace", '1', 'repeat window id criterion');
+switch_and_check("[id=$win2->{id}] focus workspace", 'other workspace', 'window id criterion');
+
+kill_all_windows;
+exit_gracefully($pid);
+
+
+#####################################################################
+# Test Back and forth
+# See #5744
+#####################################################################
+my $config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+workspace_auto_back_and_forth yes
+EOT
+
+my $pid = launch_with_config($config);
+
+cmd 'workspace 1';
+my $win1 = open_window(wm_class => 'win1');
+switch_and_check('nop', '1', 'sanity check');
+
+cmd 'workspace "other workspace"';
+my $win2 = open_window(wm_class => 'win2');
+switch_and_check('nop', 'other workspace', 'sanity check');
+
+switch_and_check('[class=win1] focus workspace', '1', 'class criterion');
+switch_and_check('[class=win2] focus workspace', 'other workspace', 'class criterion');
+switch_and_check('[class=win2] focus workspace', '1', 'repeat class criterion');
+
+cmd 'workspace 3';
+
+switch_and_check("[id=$win1->{id}] focus workspace", '1', 'window id criterion');
+switch_and_check("[id=$win1->{id}] focus workspace", '3', 'repeat window id criterion');
+switch_and_check("[id=$win2->{id}] focus workspace", 'other workspace', 'window id criterion');
+switch_and_check("[id=$win2->{id}] focus workspace", '3', 'window id criterion, back-and-forth');
+
+exit_gracefully($pid);
+
+done_testing;