gjs: Fix tests

Installed tests require GSettings schemas.

And the build-time tests are now passing.

pkgs/development/libraries/gjs/default.nix

@@ -74,9 +74,7 @@ in stdenv.mkDerivation rec {
     ./installed-tests-path.patch
   ];
 
-  # Gio test is failing
-  # https://github.com/NixOS/nixpkgs/pull/81626#issuecomment-599325843
-  doCheck = false;
+  doCheck = true;
 
   postPatch = ''
     substituteInPlace installed-tests/debugger-test.sh --subst-var-by gjsConsole $out/bin/gjs-console
@@ -95,7 +93,15 @@ in stdenv.mkDerivation rec {
   '';
 
   postInstall = ''
+    # TODO: make the glib setup hook handle this
+    installedTestsSchemaDatadir="$installedTests/share/gsettings-schemas/${pname}-${version}"
+    mkdir -p "$installedTestsSchemaDatadir"
+    mv "$installedTests/share/glib-2.0" "$installedTestsSchemaDatadir"
+  '';
+
+  postFixup = ''
     wrapProgram "$installedTests/libexec/gjs/installed-tests/minijasmine" \
+      --prefix XDG_DATA_DIRS : "$installedTestsSchemaDatadir" \
       --prefix GI_TYPELIB_PATH : "${stdenv.lib.makeSearchPath "lib/girepository-1.0" testDeps}"
   '';
 

pkgs/development/libraries/gjs/installed-tests-path.patch

@@ -1,5 +1,5 @@
 diff --git a/installed-tests/meson.build b/installed-tests/meson.build
-index 294d20c6..1e5029e0 100644
+index 7e842025..1e5029e0 100644
 --- a/installed-tests/meson.build
 +++ b/installed-tests/meson.build
 @@ -1,7 +1,7 @@
@@ -12,6 +12,19 @@ index 294d20c6..1e5029e0 100644
  
  # Simple shell script tests #
  
+diff --git a/meson.build b/meson.build
+index 084d5396..e5d73fcd 100644
+--- a/meson.build
++++ b/meson.build
+@@ -540,7 +540,7 @@ install_data('installed-tests/extra/lsan.supp',
+     install_dir: get_option('datadir') / api_name / 'lsan')
+ 
+ if get_option('installed_tests')
+-    schemadir = abs_datadir / 'glib-2.0' / 'schemas'
++    schemadir = get_option('installed_test_prefix') / 'share' / 'glib-2.0' / 'schemas'
+     install_data('installed-tests/js/org.gnome.GjsTest.gschema.xml', install_dir: schemadir)
+     meson.add_install_script('build/compile-gschemas.py', schemadir)
+ endif
 diff --git a/meson_options.txt b/meson_options.txt
 index 66f66024..008687cb 100644
 --- a/meson_options.txt