append_layout: load floating containers correctly

fixes #1739
fixes #1271

src/load_layout.c

@@ -116,6 +116,33 @@ static int json_end_map(void *ctx) {
             json_node->num = ws_name_to_number(json_node->name);
         }
 
+        // When appending JSON layout files that only contain the workspace
+        // _contents_, we might not have an upfront signal that the
+        // container we’re currently parsing is a floating container (like
+        // the “floating_nodes” key of the workspace container itself).
+        // That’s why we make sure the con is attached at the right place
+        // in the hierarchy in case it’s floating.
+        if (json_node->type == CT_FLOATING_CON) {
+            DLOG("fixing parent which currently is %p / %s\n", json_node->parent, json_node->parent->name);
+            json_node->parent = con_get_workspace(json_node->parent);
+
+            // Also set a size if none was supplied, otherwise the placeholder
+            // window cannot be created as X11 requests with width=0 or
+            // height=0 are invalid.
+            const Rect zero = {0,0,0,0};
+            if (memcmp(&(json_node->rect), &zero, sizeof(Rect)) == 0) {
+                DLOG("Geometry not set, combining children\n");
+                Con *child;
+                TAILQ_FOREACH(child, &(json_node->nodes_head), nodes) {
+                    DLOG("child geometry: %d x %d\n", child->geometry.width, child->geometry.height);
+                    json_node->rect.width += child->geometry.width;
+                    json_node->rect.height = max(json_node->rect.height, child->geometry.height);
+                }
+            }
+
+            floating_check_size(json_node);
+        }
+
         LOG("attaching\n");
         con_attach(json_node, json_node->parent, true);
         LOG("Creating window\n");

testcases/t/249-layout-restore-floating.t

@@ -0,0 +1,82 @@
+#!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 floating containers are restored in the correct place in the
+# hierarchy and get a non-zero size.
+# Ticket: #1739
+# Bug still in: 4.10.3-264-g419b73b
+use i3test;
+use File::Temp qw(tempfile);
+use IO::Handle;
+
+my $ws = fresh_workspace;
+
+my @content = @{get_ws_content($ws)};
+is(@content, 0, 'no nodes on the new workspace yet');
+
+my ($fh, $filename) = tempfile(UNLINK => 1);
+print $fh <<'EOT';
+// vim:ts=4:sw=4:et
+{
+    // floating_con with 1 children
+    "border": "none",
+    "floating": "auto_off",
+    "layout": "splith",
+    "percent": null,
+    "type": "floating_con",
+    // NOTE that "rect" is missing here.
+    "nodes": [
+        {
+            "border": "none",
+            "current_border_width": 0,
+            "floating": "user_on",
+            "geometry": {
+               "height": 384,
+               "width": 128,
+               "x": 448,
+               "y": 441
+            },
+            "name": "Splash",
+            "percent": 1,
+            "swallows": [
+               {
+                "class": "^Steam$",
+                "instance": "^Steam$",
+                "title": "^Steam$"
+               // "transient_for": "^$"
+               }
+            ],
+            "type": "con"
+        }
+    ]
+}
+EOT
+$fh->flush;
+my $reply = cmd "append_layout $filename";
+
+does_i3_live;
+
+ok($reply->[0]->{success}, 'Layout successfully loaded');
+
+cmd 'kill';
+
+ok(workspace_exists($ws), 'Workspace still exists');
+
+does_i3_live;
+
+close($fh);
+
+done_testing;