wesnoth: fix darwin and LLVM 19 compatibility (#381227)

{

  lib,

  stdenv,

  stdenvNoCC,

  fetchFromGitHub,

  cmake,

  pkg-config,

  icu,

  lua,

  curl,

  fetchpatch,

  nix-update-script,

}:

stdenv.mkDerivation rec {

stdenv.mkDerivation (finalAttrs: {

  pname = "wesnoth";

  version = "1.18.4";

  src = fetchFromGitHub {

    rev = version;

    owner = "wesnoth";

    repo = "wesnoth";

    tag = finalAttrs.version;

    hash = "sha256-c3BoTFnSUqtp71QeSCsC2teVuzsQwV8hOJtIcZdP+1E=";

  };

  # LLVM 19 removed support for types not officially supported by `std::char_traits`:

  # https://libcxx.llvm.org/ReleaseNotes/19.html#deprecations-and-removals

  # Wesnoth <1.19 relies on this previously supported non-standard behavior for

  # some types that should either have been a vector or span:

  # https://github.com/wesnoth/wesnoth/issues/9546

  # Wesnoth moved to a `std::span` wrapper for byte views in the 1.19 branch, which we apply as

  # patches until 1.20 is released.

  patches = lib.optionals (stdenv.cc.isClang && lib.versionAtLeast stdenv.cc.version "19") [

    # The next two patches are cherry-picked from https://github.com/wesnoth/wesnoth/pull/10102,

    # which is already included in the 1.19 branch.

    # Introduces the `std::span` wrapper based on `boost::span`.

    (fetchpatch {

      url = "https://github.com/wesnoth/wesnoth/commit/63266cc2c88fefa7e0792ac59d14c14e3711440c.patch";

      hash = "sha256-3Zi/njG7Kovmyd7yiKUoeu4u0QPQxxw+uLz+k9isOLU=";

    })

    # Replace all string views with spans.

    (fetchpatch {

      url = "https://github.com/wesnoth/wesnoth/commit/d3daa161eb2c02670b5ffbcf86cd0ec787f6b9ee.patch";

      hash = "sha256-9DCeZQZKE6fN91T5DCpNJsKGXbv5ihZC8UpuNkiA9zc=";

    })

    # Wesnoth <1.19 uses `std::basic_string` for lightmap computations, which is not standard compliant

    # and incompatible to LLVM 19.

    # While this was fixed in https://github.com/wesnoth/wesnoth/pull/10128, the fix is not

    # trivially backportable to 1.18 so we apply a simpler fix instead.

    ./llvm19-lightmap.patch

  ];

  nativeBuildInputs = [

    cmake

    pkg-config

    "-DENABLE_SYSTEM_LUA=ON"

  ];

  NIX_LDFLAGS = lib.optionalString stdenv.hostPlatform.isDarwin "-framework AppKit";

  postInstall = lib.optionalString stdenv.hostPlatform.isDarwin ''

    app_name="The Battle for Wesnoth"

    app_bundle="$out/Applications/$app_name.app"

    app_contents="$app_bundle/Contents"

    mkdir -p "$app_contents"

    echo "APPL????" > "$app_contents/PkgInfo"

    mv $out/bin "$app_contents/MacOS"

    mv $out/share/wesnoth "$app_contents/Resources"

    pushd ../projectfiles/Xcode

    substitute Info.plist "$app_contents/Info.plist" \

      --replace-fail ''\'''${EXECUTABLE_NAME}' wesnoth \

      --replace-fail '$(PRODUCT_BUNDLE_IDENTIFIER)' org.wesnoth.Wesnoth \

      --replace-fail ''\'''${PRODUCT_NAME}' "$app_name"

    cp -r Resources/SDLMain.nib "$app_contents/Resources/"

    install -m0644 Resources/{container-migration.plist,icon.icns} "$app_contents/Resources"

    popd

    # Make the game and dedicated server binary available for shell users

    mkdir -p "$out/bin"

    ln -s "$app_contents/MacOS/wesnothd" "$out/bin/wesnothd"

    # Symlinking the game binary is unsifficient as it would be unable to

    # find the bundle resources

    cat << EOF > "$out/bin/wesnoth"

    #!${stdenvNoCC.shell}

    open -na "$app_bundle" --args "\$@"

    EOF

    chmod +x "$out/bin/wesnoth"

  '';

  passthru.updateScript = nix-update-script {

    extraArgs = [

      "--version-regex"

      # the minor release number also denotes if this is a beta release:

      # even is stable, odd is beta

      "^(\\d+\\.\\d*[02468]\\.\\d+)$"

    ];

  };

  meta = with lib; {

  meta = {

    description = "Battle for Wesnoth, a free, turn-based strategy game with a fantasy theme";

    longDescription = ''

      The Battle for Wesnoth is a Free, turn-based tactical strategy

    '';

    homepage = "https://www.wesnoth.org/";

    license = licenses.gpl2Plus;

    maintainers = with maintainers; [ abbradar ];

    platforms = platforms.unix;

    license = lib.licenses.gpl2Plus;

    maintainers = with lib.maintainers; [

      abbradar

      niklaskorz

    ];

    platforms = lib.platforms.unix;

    mainProgram = "wesnoth";

  };

}

})

diff --git a/src/display.cpp b/src/display.cpp

index 0f6552222b7..9d50046de2f 100644

--- a/src/display.cpp

+++ b/src/display.cpp

@@ -1082,7 +1082,8 @@ void display::get_terrain_images(const map_location& loc, const std::string& tim

 		// add the directional transitions

 		tod_color acol = atod1.color + color_adjust_;

-		lt += image::get_light_string(d + 1, acol.r, acol.g, acol.b);

+		auto new_lt = image::get_light_string(d + 1, acol.r, acol.g, acol.b);

+		lt.insert(lt.end(), new_lt.begin(), new_lt.end());

 	}

 	for(int d = 0; d < 6; ++d) {

@@ -1114,7 +1115,8 @@ void display::get_terrain_images(const map_location& loc, const std::string& tim

 		// add the directional transitions

 		tod_color acol = atod1.color + color_adjust_;

-		lt += image::get_light_string(d + 7, acol.r, acol.g, acol.b);

+		auto new_lt = image::get_light_string(d + 7, acol.r, acol.g, acol.b);

+		lt.insert(lt.end(), new_lt.begin(), new_lt.end());

 	}

 	for(int d = 0; d < 6; ++d) {

@@ -1146,7 +1148,8 @@ void display::get_terrain_images(const map_location& loc, const std::string& tim

 		// add the directional transitions

 		tod_color acol = atod2.color + color_adjust_;

-		lt += image::get_light_string(d + 13, acol.r, acol.g, acol.b);

+		auto new_lt = image::get_light_string(d + 13, acol.r, acol.g, acol.b);

+		lt.insert(lt.end(), new_lt.begin(), new_lt.end());

 	}

 	if(lt.empty()){

diff --git a/src/picture.cpp b/src/picture.cpp

index e7aeddaa821..5ad1ebcbcbc 100644

--- a/src/picture.cpp

+++ b/src/picture.cpp

@@ -526,7 +526,9 @@ static surface apply_light(surface surf, const light_string& ls)

 		// decompose into atomic lightmap operations (4 chars)

 		for(std::size_t c = 0; c + 3 < ls.size(); c += 4) {

-			light_string sls = ls.substr(c, 4);

+			auto start = ls.begin() + c;

+			auto end = start + 4;

+			light_string sls(start, end);

 			// get the corresponding image and apply the lightmap operation to it

 			// This allows to also cache lightmap parts.

diff --git a/src/picture.hpp b/src/picture.hpp

index 85a3b3a15a1..a26e1e27bc7 100644

--- a/src/picture.hpp

+++ b/src/picture.hpp

@@ -120,7 +120,7 @@ std::ostream& operator<<(std::ostream&, const locator&);

  *  7-12: convex half-corners 1

  * 13-19: convex half-corners 2

  */

-typedef std::basic_string<signed char> light_string;

+typedef std::vector<signed char> light_string;