Bugfix: Fix for_window moving of assigned windows (Thanks bafain)

fixes #909

src/manage.c

@@ -402,6 +402,10 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
     /* Check if any assignments match */
     run_assignments(cwindow);
 
+    /* 'ws' may be invalid because of the assignments, e.g. when the user uses
+     * "move window to workspace 1", but had it assigned to workspace 2. */
+    ws = con_get_workspace(nc);
+
     /* If this window was put onto an invisible workspace (via assignments), we
      * render this workspace. It wouldn’t be rendered in our normal code path
      * because only the visible workspaces get rendered.

testcases/t/203-regress-assign-and-move.t

@@ -0,0 +1,64 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • http://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • http://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • http://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • http://onyxneon.com/books/modern_perl/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Verifies that you can assign a window _and_ use for_window with a move
+# command.
+# Ticket: #909
+# Bug still in: 4.4-69-g6856b23
+use i3test i3_autostart => 0;
+use X11::XCB qw(:all);
+
+my $config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+assign [instance=__i3-test-window] 2
+for_window [instance=__i3-test-window] move workspace 1
+EOT
+
+my $pid = launch_with_config($config);
+
+sub set_wm_class {
+    my ($id, $class, $instance) = @_;
+
+    # Add a _NET_WM_STRUT_PARTIAL hint
+    my $atomname = $x->atom(name => 'WM_CLASS');
+    my $atomtype = $x->atom(name => 'STRING');
+
+    $x->change_property(
+        PROP_MODE_REPLACE,
+        $id,
+        $atomname->id,
+        $atomtype->id,
+        8,
+        length($class) + length($instance) + 2,
+        "$instance\x00$class\x00"
+    );
+}
+
+# We use dont_map because i3 will not map the window on the current
+# workspace. Thus, open_window would time out in wait_for_map (2 seconds).
+my $window = open_window(
+    before_map => sub { set_wm_class($_->id, '__i3-test-window', '__i3-test-window') },
+    dont_map => 1,
+);
+$window->map;
+
+does_i3_live;
+
+exit_gracefully($pid);
+
+done_testing;