fix(awful: hotkeys_popup: widget: create_column): correct max label width detection

lib/awful/hotkeys_popup/widget.lua

@@ -484,15 +484,12 @@ function widget.new(args)
 
         local function insert_keys(_keys, _add_new_column)
             local max_label_width = 0
-            local max_label_content = ""
             local joined_labels = ""
             for i, key in ipairs(_keys) do
-                local length = string.len(key.key or '') + string.len(key.description or '')
                 local modifiers = key.mod
                 if not modifiers or modifiers == "none" then
                     modifiers = ""
                 else
-                    length = length + string.len(modifiers) + 1 -- +1 for "+" character
                     modifiers = markup.fg(self.modifiers_fg, modifiers.."+")
                 end
                 local rendered_hotkey = markup.font(self.font,
@@ -500,16 +497,15 @@ function widget.new(args)
                 ) .. markup.font(self.description_font,
                     key.description or ""
                 )
-                if length > max_label_width then
-                    max_label_width = length
-                    max_label_content = rendered_hotkey
+                local label_width = wibox.widget.textbox.get_markup_geometry(rendered_hotkey, s).width
+                if label_width > max_label_width then
+                    max_label_width = label_width
                 end
                 joined_labels = joined_labels .. rendered_hotkey .. (i~=#_keys and "\n" or "")
                 end
             current_column.layout:add(wibox.widget.textbox(joined_labels))
-            local max_width, _ = wibox.widget.textbox(max_label_content):get_preferred_size(s)
-            max_width = max_width + self.group_margin
-            if not current_column.max_width or max_width > current_column.max_width then
+            local max_width = max_label_width + self.group_margin
+            if not current_column.max_width or (max_width > current_column.max_width) then
                 current_column.max_width = max_width
             end
             -- +1 for group label:

lib/wibox/widget/textbox.lua

@@ -373,6 +373,26 @@ function textbox.mt.__call(_, ...)
     return new(...)
 end
 
+--- Get geometry of text label, as if textbox would be created for it on the screen.
+--
+-- @tparam string text The text content, pango markup supported.
+-- @tparam[opt=nil] integer|screen s The screen on which the textbox would be displayed.
+-- @tparam[opt=beautiful.font] string font The font description as string.
+-- @treturn table Geometry (width, height) hashtable.
+function textbox.get_markup_geometry(text, s, font)
+    font = font or beautiful.font
+    local pctx = PangoCairo.font_map_get_default():create_context()
+    local playout = Pango.Layout.new(pctx)
+    playout:set_font_description(beautiful.get_font(font))
+    local dpi_scale = beautiful.xresources.get_dpi(s)
+    pctx:set_resolution(dpi_scale)
+    playout:context_changed()
+    local attr, parsed = Pango.parse_markup(text, -1, 0)
+    playout.attributes, playout.text = attr, parsed
+    local _, logical = playout:get_pixel_extents()
+    return logical
+end
+
 --@DOC_widget_COMMON@
 
 --@DOC_object_COMMON@

spec/wibox/widget/textbox_spec.lua

@@ -5,6 +5,17 @@
 
 local textbox = require("wibox.widget.textbox")
 
+local test_dpi_value = 192
+_G.screen = {
+    { geometry = { x = 0, y = 0, width = 1920, height = 1080 }, index = 1, dpi=test_dpi_value },
+}
+local beautiful = require("beautiful")
+local xresources = require("beautiful.xresources")
+beautiful.font = 'Monospace 10'
+xresources.get_dpi = function(_) return test_dpi_value end
+package.loaded["beautiful"] = beautiful
+package.loaded["beautiful.xresources"] = xresources
+
 describe("wibox.widget.textbox", function()
     local widget
     before_each(function()
@@ -113,6 +124,29 @@ describe("wibox.widget.textbox", function()
             assert.is.equal(2, layout_changed)
         end)
     end)
+
+    describe("auxiliary", function()
+
+        it("can compute text geometry w/default font", function()
+            local text = "<b><i>test</i></b>"
+            local s = 1
+            local pango_geometry = textbox.get_markup_geometry(text, s)
+            local actual_textbox_width, actual_textbox_height = textbox(text):get_preferred_size(s)
+            assert.is.equal(pango_geometry.width, actual_textbox_width)
+            assert.is.equal(pango_geometry.height, actual_textbox_height)
+        end)
+
+        it("can compute text geometry w/hardcoded font", function()
+            local text = "<span font='Monospace 16'><b><i>test</i></b></span>"
+            local s = 1
+            local pango_geometry = textbox.get_markup_geometry(text, s)
+            local actual_textbox_width, actual_textbox_height = textbox(text):get_preferred_size(s)
+            assert.is.equal(pango_geometry.width, actual_textbox_width)
+            assert.is.equal(pango_geometry.height, actual_textbox_height)
+        end)
+
+    end)
+
 end)
 
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