desktopToDarwinBundle: fix 16x, 32x app icons (#358247)

pkgs/build-support/setup-hooks/desktop-to-darwin-bundle.sh

@@ -92,6 +92,7 @@ convertIconTheme() {
 
         echo "desktopToDarwinBundle: resizing icon $in to $out, size $dim" >&2
         magick convert -scale "${dim}x${dim}" -density "$density" -units PixelsPerInch "$in" "$out"
+        convertIfUnsupportedIcon "$out" "$iconSize" "$scale"
     }
 
     function synthesizeIcon() {
@@ -107,11 +108,27 @@ convertIconTheme() {
             echo "desktopToDarwinBundle: rasterizing svg $in to $out, size $dim" >&2
             rsvg-convert --keep-aspect-ratio --width "$dim" --height "$dim" "$in" --output "$out"
             magick convert -density "$density" -units PixelsPerInch "$out" "$out"
+            convertIfUnsupportedIcon "$out" "$iconSize" "$scale"
         else
             return 1
         fi
     }
 
+    # macOS does not correctly display 16x and 32x png icons on app bundles
+    # they need to be converted to rgb+mask (argb is supported only from macOS 11)
+    function convertIfUnsupportedIcon() {
+        local -r in=$1
+        local -r iconSize=$2
+        local -r scale=$3
+        local -r out=${in%.png}.rgb
+
+        if [[ ($scale -eq 1) && ($iconSize -eq 32 || $iconSize -eq 16) ]]; then
+            echo "desktopToDarwinBundle: converting ${iconSize}x icon to rgb" >&2
+            icnsutil convert "$out" "$in"
+            rm "$in"
+        fi
+    }
+
     function getIcons() {
         local -r sharePath=$1
         local -r iconname=$2
@@ -151,6 +168,7 @@ convertIconTheme() {
                     fixed)
                         local density=$((72 * scale))x$((72 * scale))
                         magick convert -density "$density" -units PixelsPerInch "$icon" "$result"
+                        convertIfUnsupportedIcon "$result" "$iconSize" "$scale"
                         foundIcon=OTHER
                         ;;
                     threshold)

pkgs/development/python-modules/icnsutil/default.nix

@@ -4,6 +4,7 @@
   fetchFromGitHub,
   python,
   pythonOlder,
+  pillow,
 }:
 
 buildPythonPackage rec {
@@ -20,6 +21,8 @@ buildPythonPackage rec {
     hash = "sha256-tiq8h6s2noWLBIOIWcj8jfSqJFN01ee2uoHN4aFwn7s=";
   };
 
+  dependencies = [ pillow ];
+
   checkPhase = ''
     ${python.interpreter} tests/test_icnsutil.py
     ${python.interpreter} tests/test_cli.py