6 files changed, 33 insertions, 12 deletions

diff --git a/include/sway/config.h b/include/sway/config.h
index ab494e78..46ca7cee 100644
--- a/include/sway/config.h
+++ b/include/sway/config.h
@@ -465,6 +465,7 @@ struct sway_config {
         int floating_border_thickness;
         enum edge_border_types hide_edge_borders;
         enum edge_border_types saved_edge_borders;
+        bool hide_lone_tab;
 
         // border colors
         struct {
diff --git a/sway/commands/hide_edge_borders.c b/sway/commands/hide_edge_borders.c
index 84a217b8..6120a17f 100644
--- a/sway/commands/hide_edge_borders.c
+++ b/sway/commands/hide_edge_borders.c
@@ -5,10 +5,16 @@
 
 struct cmd_results *cmd_hide_edge_borders(int argc, char **argv) {
         struct cmd_results *error = NULL;
-        if ((error = checkarg(argc, "hide_edge_borders", EXPECTED_EQUAL_TO, 1))) {
+        if ((error = checkarg(argc, "hide_edge_borders", EXPECTED_AT_LEAST, 1))) {
                 return error;
         }
 
+        if (strcmp(*argv, "--i3") == 0) {
+                config->hide_lone_tab = true;
+                ++argv;
+                --argc;
+        }
+
         if (strcmp(argv[0], "none") == 0) {
                 config->hide_edge_borders = E_NONE;
         } else if (strcmp(argv[0], "vertical") == 0) {
@@ -23,7 +29,7 @@ struct cmd_results *cmd_hide_edge_borders(int argc, char **argv) {
                 config->hide_edge_borders = E_SMART_NO_GAPS;
         } else {
                 return cmd_results_new(CMD_INVALID, "Expected 'hide_edge_borders "
-                                "<none|vertical|horizontal|both|smart|smart_no_gaps>'");
+                                "[--i3] <none|vertical|horizontal|both|smart|smart_no_gaps>'");
         }
         config->saved_edge_borders = config->hide_edge_borders;
 
diff --git a/sway/config.c b/sway/config.c
index 4cd21bbc..48bbd1ea 100644
--- a/sway/config.c
+++ b/sway/config.c
@@ -261,6 +261,7 @@ static void config_defaults(struct sway_config *config) {
         config->floating_border_thickness = 2;
         config->hide_edge_borders = E_NONE;
         config->saved_edge_borders = E_NONE;
+        config->hide_lone_tab = false;
 
         // border colors
         set_color(config->border_colors.focused.border, 0x4C7899);
diff --git a/sway/desktop/render.c b/sway/desktop/render.c
index 92e623ef..5df16075 100644
--- a/sway/desktop/render.c
+++ b/sway/desktop/render.c
@@ -841,6 +841,14 @@ static void render_containers_stacked(struct sway_output *output,
 
 static void render_containers(struct sway_output *output,
                 pixman_region32_t *damage, struct parent_data *parent) {
+        if (config->hide_lone_tab && parent->children->length == 1) {
+                struct sway_container *child = parent->children->items[0];
+                if (child->view) {
+                        render_containers_linear(output,damage, parent);
+                        return;
+                }
+        }
+
         switch (parent->layout) {
         case L_NONE:
         case L_HORIZ:
diff --git a/sway/sway.5.scd b/sway/sway.5.scd
index 1affca5f..c0ec85cd 100644
--- a/sway/sway.5.scd
+++ b/sway/sway.5.scd
@@ -493,8 +493,10 @@ The default colors are:
         This affects new workspaces only, and is used when the workspace doesn't
         have its own gaps settings (see: workspace <ws> gaps ...).
 
-*hide_edge_borders* none|vertical|horizontal|both|smart|smart_no_gaps
-        Hides window borders adjacent to the screen edges. Default is _none_.
+*hide_edge_borders* [--i3] none|vertical|horizontal|both|smart|smart_no_gaps
+        Hides window borders adjacent to the screen edges. Default is _none_. The
+        _--i3_ option enables i3-compatible behavior to hide the title bar on tabbed
+        and stacked containers with one child.
 
 *input* <input_device> <input-subcommands...>
         For details on input subcommands, see *sway-input*(5).
diff --git a/sway/tree/view.c b/sway/tree/view.c
index ca13def7..14cc07d9 100644
--- a/sway/tree/view.c
+++ b/sway/tree/view.c
@@ -246,14 +246,17 @@ void view_autoconfigure(struct sway_view *view) {
         // In a tabbed or stacked container, the container's y is the top of the
         // title area. We have to offset the surface y by the height of the title,
         // bar, and disable any top border because we'll always have the title bar.
-        enum sway_container_layout layout = container_parent_layout(con);
-        if (layout == L_TABBED && !container_is_floating(con)) {
-                y_offset = container_titlebar_height();
-                con->border_top = false;
-        } else if (layout == L_STACKED && !container_is_floating(con)) {
-                list_t *siblings = container_get_siblings(con);
-                y_offset = container_titlebar_height() * siblings->length;
-                con->border_top = false;
+        list_t *siblings = container_get_siblings(con);
+        bool show_titlebar = siblings->length > 1 || !config->hide_lone_tab;
+        if (show_titlebar && !container_is_floating(con)) {
+                enum sway_container_layout layout = container_parent_layout(con);
+                if (layout == L_TABBED) {
+                        y_offset = container_titlebar_height();
+                        con->border_top = false;
+                } else if (layout == L_STACKED) {
+                        y_offset = container_titlebar_height() * siblings->length;
+                        con->border_top = false;
+                }
         }
 
         double x, y, width, height;