Aligning 'regex' with other PR / Minor readability improvements

https://github.com/awesomeWM/awesome/issues/2596

Re-matched regex used elsewhere & updated test cases for "." in filename

Allowed for alternative extensions to be found even if specified

Reverted the change of behaviour but adjusted code for readability

Small readability change

Avoided delay searches that would never work

Untabify

Reverted possible [unlikely/undesired] behaviour changes

Untabify

lib/menubar/utils.lua

@@ -127,8 +127,8 @@ local all_icon_sizes = {
     '16x16'
 }
 
---- List of supported icon formats.
-local supported_icon_formats = { png = 1, xpm = 2, svg = 3 }
+--- List of supported icon exts.
+local supported_icon_file_exts = { png = 1, xpm = 2, svg = 3 }
 
 local icon_lookup_path = nil
 --- Get a list of icon lookup paths.
@@ -214,29 +214,28 @@ function utils.lookup_icon_uncached(icon_file)
         return false
     end
 
-    local icon_file_ext = icon_file:match(".*%.(.-)$")
-    if icon_file:sub(1, 1) == '/' and supported_icon_formats[icon_file_ext] then
-        -- If the path to the icon is absolute and its format is
-        -- supported, do not perform a lookup.
+    local icon_file_ext = icon_file:match(".+%.(.*)$")
+    if icon_file:sub(1, 1) == '/' and supported_icon_file_exts[icon_file_ext] then
+        -- If the path to the icon is absolute do not perform a lookup [nil if unsupported ext or missing]
         return gfs.file_readable(icon_file) and icon_file or nil
     else
+        -- Look for the requested file in the lookup path
         for _, directory in ipairs(get_icon_lookup_path()) do
-            local directory_file = directory .. "/" .. icon_file
-            if supported_icon_formats[icon_file_ext] and
-                    gfs.file_readable(directory_file) then
-                return directory_file
+            local possible_file = directory .. "/" .. icon_file
+            -- Check to see if file exists if requested with a valid extension
+            if supported_icon_file_exts[icon_file_ext] and gfs.file_readable(possible_file) then
+                return possible_file
             else
-                -- Icon is probably specified without path and format,
-                -- like 'firefox'. Try to add supported extensions to
-                -- it and see if such file exists.
-                for format, _ in pairs(supported_icon_formats) do
-                    local possible_file = directory_file .. "." .. format
-                    if gfs.file_readable(possible_file) then
-                        return possible_file
+                -- Find files with any supported extension if icon specified without, eg: 'firefox'
+                for ext, _ in pairs(supported_icon_file_exts) do
+                    local possible_file_new_ext = possible_file .. "." .. ext
+                    if gfs.file_readable(possible_file_new_ext) then
+                        return possible_file_new_ext
                     end
                 end
             end
         end
+        -- No icon found
         return false
     end
 end

spec/menubar/usr/share/.filename.png

@@ -0,0 +1 @@
+../../../../icons/awesome16.png

spec/menubar/usr/share/icons/.filename.png

@@ -0,0 +1 @@
+../../../icons/fallback.png

spec/menubar/utils_spec.lua

@@ -76,60 +76,69 @@ describe("menubar.utils lookup_icon_uncached", function()
         assert_found_in_path('awesome2', '/.icons/awesome/scalable/apps/awesome2.png')
     end)
 
--- Check for no argument :: if not icon_file or icon_file == "" then
+    -- No argument
     it('no icon specified', function()
         assert.is_false(utils.lookup_icon_uncached())
-        assert.is_false(utils.lookup_icon_uncached(nil)) -- Same as above?
+        assert.is_false(utils.lookup_icon_uncached(nil))
         assert.is_false(utils.lookup_icon_uncached(false))
         assert.is_false(utils.lookup_icon_uncached(''))
     end)
 
--- Check for icon not in search path :: if icon_file:sub(1, 1) == '/' and supported_icon_formats[icon_file_ext] then
-    it('finds icons even those not in the search paths when full path specified', function()
+    -- Full path and filename with expected extension
+    it('finds icons even those not in the search paths when full path is specified', function()
 
         -- Shimmed icon base directories contain the following icons:
         --
         --     usr/share/icon5.png
         --     usr/share/icon6.xpm
         --     usr/share/icon7.svg
+        --     usr/share/icons/.filename.png
 
         assert_found_in_path('/usr/share/icon5.png', '/usr/share/icon5.png')
         assert_found_in_path('/usr/share/icon6.xpm', '/usr/share/icon6.xpm')
         assert_found_in_path('/usr/share/icon7.svg', '/usr/share/icon7.svg')
 
-        assert.is_same(nil, utils.lookup_icon_uncached('/.png')) -- supported file does not exist in location
-        assert.is_same(nil, utils.lookup_icon_uncached('/blah/icon6.png')) -- supported file does not exist in location
+        assert_found_in_path('/usr/share/.filename.png', '/usr/share/.filename.png')
+
+        assert.is_nil(utils.lookup_icon_uncached('/blah/icon6.png')) -- supported file does not exist in location
+        assert.is_nil(utils.lookup_icon_uncached('/.png')) -- path & supported ext - but also not found
     end)
 
--- Check icon with specified extension matching :: if supported_icon_formats[icon_file_ext] and
-    it('finds icons with specified supported extension in search path', function()
+   -- Filename with supported extension
+    it('finds icons with specified supported extension in the search path', function()
 
         -- Shimmed icon base directories contain the following icons:
         --
         --     .icons/icon5.png
         --     .icons/icon6.xpm
         --     .icons/icon7.svg
+        --     usr/share/icons/.filename.png
 
         assert_found_in_path('icon5.png', '/.icons/icon5.png')
         assert_found_in_path('icon6.xpm', '/.icons/icon6.xpm')
         assert_found_in_path('icon7.svg', '/.icons/icon7.svg')
 
+        assert_found_in_path('.filename.png', '/usr/share/icons/.filename.png')
+
         --  Will fail as file does not exist (but extension is supported)
         assert.is_false(utils.lookup_icon_uncached('icon8.png'))
     end)
 
--- Check icon with no (or invalid) extension matching :: if NOT supported_icon_formats[icon_file_ext]
+    -- Find icon with no (or invalid) extension matching
     it('finds icons without specified path or extension', function()
 
         -- Shimmed icon base directories contain the following icons:
         --
         --     .icons/icon6.xpm
         --     .icons/icon7.svg
+        --     usr/share/icons/.filename.png
 
-        assert_found_in_path('icon6', '/.icons/icon6.xpm') -- Similar to original tests and testing xpm extension
-        assert_found_in_path('icon7', '/.icons/icon7.svg') -- Similar to original tests and testing svg extension
+        assert_found_in_path('icon6', '/.icons/icon6.xpm')
+        assert_found_in_path('icon7', '/.icons/icon7.svg')
 
-        assert.is_false(utils.lookup_icon_uncached('/png')) -- supported file does not exist in given location
+        assert_found_in_path('.filename', '/usr/share/icons/.filename.png')
+
+        assert.is_false(utils.lookup_icon_uncached('/png')) -- path & no ext
         assert.is_false(utils.lookup_icon_uncached('.png')) -- file does not exist
         assert.is_false(utils.lookup_icon_uncached('png')) -- file does not exist
         assert.is_false(utils.lookup_icon_uncached('icon9')) -- file does not exist