Adjust data locations for macOS app bundle

The application bundle is relocatable, so the data locations must be
set at runtime.

.gitlab-ci.yml

@@ -98,7 +98,7 @@ macos:
   variables:
     CCACHE_DIR: /Users/Shared/work/ccache
     MM_REPO_URL: https://gitlab.com/dehesselle/meld_macos.git
-    MM_REPO_REF: 40a3e6b090650de6fcf3e684fc7dac527b4e9310
+    MM_REPO_REF: cf0d881d2bfdc1607f0e2bd11bcd9bd215e74f1b
     MELD_BUILD: $CI_PIPELINE_IID
     REP_DIR: $CI_PROJECT_DIR
     SDKROOT: /opt/sdks/MacOSX11.3.sdk

bin/meld

@@ -410,6 +410,23 @@ def setup_glib_logging():
         pass
 
 
+def setup_macos_application_bundle():
+    # When running from inside an application bundle, adjust paths relative
+    # to the location of the main binary.
+    if "Contents/MacOS" in sys.executable:
+        meld.conf.DATADIR = os.path.abspath(
+            os.path.join(
+                os.path.dirname(os.path.realpath(sys.executable)),
+                "../Resources/share/meld"
+            )
+        )
+        meld.conf.LOCALEDIR = os.path.abspath(
+            os.path.join(
+                os.path.dirname(meld.conf.DATADIR), "locale"
+            )
+        )
+
+
 def environment_hacks():
     # MSYSTEM is set by git, and confuses our
     # msys-packaged version's library search path -
@@ -449,6 +466,7 @@ def run_application():
 
 
 def main():
+    setup_macos_application_bundle()
     environment_hacks()
     setup_logging()
     disable_stdout_buffering()