menubar.utils.parse_desktop_file: Improve type handling

This is a slight API break, but should not cause many problems for
people. This makes parse_desktop_file() handle the type of keys
correctly, so that e.g. booleans are actually parsed as booleans. Also,
locale-sensitive entries are now looked up in a way that obeys the
current locale.

Signed-off-by: Uli Schlachter <psychon@znc.in>

lib/menubar/utils.lua

@@ -50,12 +50,53 @@ local escape_sequences = {
     [ [[\t]] ]  = '\t',
 }
 
---- The keys in desktop entries whose values are lists of strings.
-local list_keys = {
-    Categories = true,
-    OnlyShowIn = true,
-    NotShowIn = true,
-}
+-- Maps keys in desktop entries to suitable getter function.
+-- The order of entries is as in the spec.
+-- https://standards.freedesktop.org/desktop-entry-spec/latest/ar01s05.html
+local keys_getters
+do
+    local function get_string(kf, key)
+        return kf:get_string("Desktop Entry", key)
+    end
+    local function get_strings(kf, key)
+        return kf:get_string_list("Desktop Entry", key, nil)
+    end
+    local function get_localestring(kf, key)
+        return kf:get_locale_string("Desktop Entry", key, nil)
+    end
+    local function get_localestrings(kf, key)
+        return kf:get_locale_string_list("Desktop Entry", key, nil, nil)
+    end
+    local function get_boolean(kf, key)
+        return kf:get_boolean("Desktop Entry", key)
+    end
+
+    keys_getters = {
+        Type = get_string,
+        Version = get_string,
+        Name = get_localestring,
+        GenericName = get_localestring,
+        NoDisplay = get_boolean,
+        Comment = get_localestring,
+        Icon = get_localestring,
+        Hidden = get_boolean,
+        OnlyShowIn = get_strings,
+        NotShowIn = get_strings,
+        DBusActivatable = get_boolean,
+        TryExec = get_string,
+        Exec = get_string,
+        Path = get_string,
+        Terminal = get_boolean,
+        Actions = get_strings,
+        MimeType = get_strings,
+        Categories = get_strings,
+        Implements = get_strings,
+        Keywords = get_localestrings,
+        StartupNotify = get_boolean,
+        StartupWMClass = get_string,
+        URL = get_string,
+    }
+end
 
 -- Private section
 
@@ -273,18 +314,17 @@ function utils.parse_desktop_file(file)
     end
 
     for _, key in pairs(keyfile:get_keys("Desktop Entry")) do
-        if list_keys[key] then
-            program[key] = keyfile:get_string_list("Desktop Entry", key)
-        else
-            program[key] = keyfile:get_string("Desktop Entry", key)
+        local getter = keys_getters[key] or function(kf, k)
+            return kf:get_string("Desktop Entry", k)
         end
+        program[key] = getter(keyfile, key)
     end
 
     -- In case the (required) 'Name' entry was not found
     if not program.Name or program.Name == '' then return nil end
 
-    -- Don't show program if NoDisplay attribute is false
-    if program.NoDisplay and string.lower(program.NoDisplay) == "true" then
+    -- Don't show program if NoDisplay attribute is true
+    if program.NoDisplay then
         program.show = false
     else
         -- Only check these values is NoDisplay is true (or non-existent)