fix(rusile): Adjust module loader to Darwin's shared module extension

Makefile.am

@@ -178,9 +178,11 @@ if FONT_VARIATIONS
 CARGO_FEATURE_ARGS += --features variations
 endif
 
-rusile.so: $(rusile_so_SOURCES) $(bin_PROGRAMS)
+@builddir@/target/@RUST_TARGET_SUBDIR@/librusile.$(SHARED_LIB_EXT): $(rusile_so_SOURCES) $(bin_PROGRAMS)
 	$(CARGO_ENV) $(CARGO) build $(CARGO_VERBOSE) --target $(CARGO_TARGET_TRIPLE) $(RUSILE_FEATURE_ARG) $(CARGO_RELEASE_ARGS) -p rusile
-	$(INSTALL) @builddir@/target/@RUST_TARGET_SUBDIR@/lib$@ $@
+
+rusile.so: @builddir@/target/@RUST_TARGET_SUBDIR@/librusile.$(SHARED_LIB_EXT)
+	$(INSTALL) $< $@
 
 DEPDIR := .deps
 LOCALFONTS := FONTCONFIG_FILE=$(PWD)/fontconfig.conf

configure.ac

@@ -247,7 +247,7 @@ AC_SUBST([ICU_LIBS])
 
 case $host_os in
     darwin*)
-        SHARED_LIB_EXT="so"
+        SHARED_LIB_EXT="dylib"
         ;;
     cygwin*|mingw*)
         SHARED_LIB_EXT="dll"

core/pathsetup.lua.in

@@ -43,6 +43,9 @@ end
 -- Prepend paths specifically for C modules.
 local function prependCPath (path)
    package.cpath = prepend_and_dedup(path .. "/?.@SHARED_LIB_EXT@", package.cpath)
+   if "@SHARED_LIB_EXT@" ~= "so" then
+      package.cpath = prepend_and_dedup(path .. "/?.so", package.cpath)
+   end
 end
 
 -- Take a given path and iterate over permutations of paths that LuaRocks might have installed a rock to that are