Make test suite work with cross-related options

Because of skepticism I received in #224, I made this PR which keeps the
testsuite and CI improvements but doesn't add any new build options. I
hope this would be less controversial:

 - no new knobs
 - tests for those using existing build options
 - CI tests `build_introspection_data = false`

12 files changed, 105 insertions, 69 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d8c72acb..4e4572e1 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -88,6 +88,27 @@ fedora-x86_64-subprojects:
       - "${CI_PROJECT_DIR}/_build/meson-logs"
       - public
 
+fedora-x86_64-no-introspection-data:
+  stage: build
+  variables:
+    CCACHE_BASEDIR: "${CI_PROJECT_DIR}"
+    CCACHE_DIR: "${CI_PROJECT_DIR}/_ccache"
+    CFLAGS: "-Werror"
+  script:
+    - python3 -m pip install --user mako markdown
+    - meson --prefix /usr --libdir /usr/lib64 --buildtype debug -Dbuild_introspection_data=false -Dpython=python3 _build .
+    - cd _build
+    - ninja
+    - meson test --print-errorlogs --suite=gobject-introspection --no-suite=glib
+  except:
+    - tags
+  artifacts:
+    when: always
+    name: "gi-_${CI_COMMIT_REF_NAME}"
+    paths:
+      - "${CI_PROJECT_DIR}/_build/meson-logs"
+      - public
+
 fedora-x86_64-python3.6:
   stage: build
   variables:
diff --git a/MSVC.README.rst b/MSVC.README.rst
index ec5ddb56..0c0dd409 100644
--- a/MSVC.README.rst
+++ b/MSVC.README.rst
@@ -71,7 +71,7 @@ using Ninja or the generated Visual Studio projects.
 Additional notes for building and running against Python 3.8.x and later
 ------------------------------------------------------------------------
 Python 3.8.x and later made restrictions on where DLLs are searched for third-party
-modules, which will therefore affect how the Python tools in tools/ look for dependent
+modules, which will therefore affect how the Python tools in ``tools/`` look for dependent
 DLLs, as they rely on a C Python module, _giscanner.pyd, as the paths in %PATH% are
 no longer referred to, except for system-supplied DLLs in their designated locations
 on the system.  In order to cope with this, DLLs are being searched for in the
diff --git a/gir/meson.build b/gir/meson.build
index 557e5517..61fbdfb1 100644
--- a/gir/meson.build
+++ b/gir/meson.build
@@ -178,11 +178,20 @@ endforeach
 # out of date.
 glib_files += files('glib-2.0.c')
 
+gir_giscanner_pymod = []
+gir_giscanner_built_files = []
+if not get_option('gi_cross_use_prebuilt_gi')
+  # The right thing to do is just make these dependencies of the
+  # `configure_file` python executable, but that isn't yet supported.
+  gir_giscanner_pymod = giscanner_pymod
+  gir_giscanner_built_files = giscanner_built_files
+endif
+
 glib_gir = custom_target('gir-glib',
   input: glib_files,
   output: 'GLib-2.0.gir',
-  depends: giscanner_pymod,
-  depend_files: giscanner_built_files,
+  depends: gir_giscanner_pymod,
+  depend_files: gir_giscanner_built_files,
   install: true,
   install_dir: girdir,
   command: glib_command + [
@@ -244,8 +253,8 @@ gobject_files += files('gobject-2.0.c')
 gobject_gir = custom_target('gir-gobject',
   input: gobject_files,
   output: 'GObject-2.0.gir',
-  depends: [glib_gir, giscanner_pymod],
-  depend_files: giscanner_built_files,
+  depends: [glib_gir, gir_giscanner_pymod],
+  depend_files: gir_giscanner_built_files,
   install: true,
   install_dir: girdir,
   command: gobject_command + [
@@ -291,8 +300,8 @@ gmodule_files += files('gmodule-2.0.c')
 gir_files += custom_target('gir-gmodule',
   input: gmodule_files,
   output: 'GModule-2.0.gir',
-  depends: [glib_gir, giscanner_pymod],
-  depend_files: giscanner_built_files,
+  depends: [glib_gir, gir_giscanner_pymod],
+  depend_files: gir_giscanner_built_files,
   install: true,
   install_dir: girdir,
   command: gmodule_command + [
@@ -380,8 +389,8 @@ gio_files += files('gio-2.0.c')
 gio_gir = custom_target('gir-gio',
   input: gio_files,
   output: 'Gio-2.0.gir',
-  depends: [gobject_gir, giscanner_pymod],
-  depend_files: giscanner_built_files,
+  depends: [gobject_gir, gir_giscanner_pymod],
+  depend_files: gir_giscanner_built_files,
   install: true,
   install_dir: girdir,
   command: gio_command + [
@@ -417,8 +426,8 @@ endif
 gir_files += custom_target('gir-girepository',
   input: girepo_gir_sources,
   output: 'GIRepository-2.0.gir',
-  depends: [gobject_gir, giscanner_pymod, girepo_lib],
-  depend_files: giscanner_built_files,
+  depends: [gobject_gir, gir_giscanner_pymod, girepo_lib],
+  depend_files: gir_giscanner_built_files,
   install: true,
   install_dir: girdir,
   command: girepository_command + [
diff --git a/girepository/meson.build b/girepository/meson.build
index c8ef6aa9..786749a9 100644
--- a/girepository/meson.build
+++ b/girepository/meson.build
@@ -185,13 +185,6 @@ girepo_lib = shared_library('girepository-1.0',
   install: true,
 )
 
-# Copy to builddir for use with giscanner/dumper.py when running uninstalled
-configure_file(input : 'gdump.c',
-  output : 'gdump.c',
-  copy: true,
-  install_dir: join_paths(get_option('datadir'), 'gobject-introspection-1.0'),
-)
-
 girepo_dep = declare_dependency(
   link_with: girepo_lib,
   dependencies: [glib_dep, gobject_dep, gio_dep, gmodule_dep],
diff --git a/giscanner/dumper.py b/giscanner/dumper.py
index f61c46c1..22afd61e 100644
--- a/giscanner/dumper.py
+++ b/giscanner/dumper.py
@@ -102,7 +102,7 @@ class DumpCompiler(object):
 
         tpl_args = {}
         if self._uninst_srcdir is not None:
-            gdump_path = os.path.join(self._uninst_srcdir, 'girepository', 'gdump.c')
+            gdump_path = os.path.join(self._uninst_srcdir, 'giscanner', 'gdump.c')
         else:
             try:
                 gdump_path = GDUMP_PATH
diff --git a/giscanner/meson.build b/giscanner/meson.build
index 098b7b6b..41edcd44 100644
--- a/giscanner/meson.build
+++ b/giscanner/meson.build
@@ -44,6 +44,13 @@ foreach f : giscanner_files
                                           configuration : giscanner_conf_data)
 endforeach
 
+# Copy to builddir for use with dumper.py when running uninstalled
+configure_file(input : '../girepository/gdump.c',
+  output : 'gdump.c',
+  copy: true,
+  install_dir: join_paths(get_option('datadir'), 'gobject-introspection-1.0'),
+)
+
 install_subdir('doctemplates', install_dir: giscannerdir)
 
 # XXX: this doesn't track the input, but there is nothing to copy many files
diff --git a/meson.build b/meson.build
index 9638a5ab..4460e40c 100644
--- a/meson.build
+++ b/meson.build
@@ -218,14 +218,19 @@ subdir('giscanner')
 # scenarios where running target binaries through software emulation
 # is not possible (due to the SW emulation missing support for target HW).
 if get_option('build_introspection_data') == true
-    subdir('gir')
+  subdir('gir')
+else
+  # for tests
+  typelibs = disabler()
+  gobject_gir = disabler()
+  gio_gir = disabler()
 endif
 subdir('docs')
 
 # The tests will also run, which is not possible if they
 # were built for a different architecture.
 if not meson.is_cross_build()
-    subdir('tests')
+  subdir('tests')
 endif
 
 install_data('Makefile.introspection', install_dir: join_paths(get_option('datadir'), 'gobject-introspection-1.0'))
diff --git a/tests/meson.build b/tests/meson.build
index b240749e..d5b76342 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -45,13 +45,17 @@ test_install_dir = join_paths(get_option('datadir'), 'gobject-introspection-1.0'
 
 install_data(installed_sources, install_dir: test_install_dir)
 
+# Will be overridden to newly built one in common-case regular, non-cross
+# build.
+test_girscanner = find_program('g-ir-scanner', native: true, required : false)
+test_gircompiler = find_program('g-ir-compiler', native: false, required : false)
+
 # Generate everything.h and everything.c:
 test_everything_files = custom_target('everything',
   output: ['everything.h', 'everything.c'],
   depends: typelibs,
   command: [
-    python,
-    girscanner,
+    test_girscanner,
     '--quiet',
     '--generate-typelib-tests=Everything,@OUTPUT0@,@OUTPUT1@',
     '--function-decoration=_GI_TEST_EXTERN',
@@ -103,14 +107,15 @@ test_typelibs = []
 # well. Though, this could work differently altogether. Instead one could
 # generate appropriate pkg-config files and point PKG_CONFIG_PATH to them,
 # leaving all invocations of g-ir-scanner as is.
-if glib_dep.type_name() == 'pkgconfig'
-  test_gir_files += custom_target('gir-everything',
+if (glib_dep.type_name() == 'pkgconfig' and
+    test_girscanner.found() and
+    get_option('build_introspection_data') == true)
+  test_gir_files += [custom_target('gir-everything',
     input: test_everything_sources + test_everything_headers,
     output: 'Everything-1.0.gir',
     depends: [everything_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -128,15 +133,14 @@ if glib_dep.type_name() == 'pkgconfig'
       extra_giscanner_args,
       '@INPUT@',
     ]
-  )
+  )]
 
-  test_gir_files += custom_target('gir-gimarshallingtests',
+  test_gir_files += [custom_target('gir-gimarshallingtests',
     input: test_marshalling_sources + test_marshalling_headers,
     output: 'GIMarshallingTests-1.0.gir',
     depends: [gimarshallingtests_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -155,14 +159,14 @@ if glib_dep.type_name() == 'pkgconfig'
       extra_giscanner_args,
       '@INPUT@',
     ]
-  )
+  )]
 
   foreach gir : test_gir_files
     test_typelibs += custom_target('generate-typelib-@0@'.format(gir).underscorify(),
       input: gir,
       output: '@BASENAME@.typelib',
       depends: [gobject_gir, ],
-      command: [gircompiler, '-o', '@OUTPUT@', '@INPUT@',
+      command: [test_gircompiler, '-o', '@OUTPUT@', '@INPUT@',
                 '--includedir', join_paths(build_root, 'gir'),
                 '--includedir', meson.current_build_dir()
       ],
@@ -183,6 +187,10 @@ if glib_dep.type_name() == 'pkgconfig'
 endif
 
 subdir('offsets')
-subdir('warn')
+if get_option('build_introspection_data') == true
+  subdir('warn')
+endif
 subdir('scanner')
-subdir('repository')
+if get_option('build_introspection_data') == true
+  subdir('repository')
+endif
diff --git a/tests/offsets/meson.build b/tests/offsets/meson.build
index f6a497f6..970e54cf 100644
--- a/tests/offsets/meson.build
+++ b/tests/offsets/meson.build
@@ -18,8 +18,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Offsets-1.0.gir',
     depends: [test_offsets_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -45,7 +44,7 @@ if glib_dep.type_name() == 'pkgconfig'
     input: test_offsets_gir,
     output: '@BASENAME@.typelib',
     depends: [gobject_gir, ],
-    command: [gircompiler, '-o', '@OUTPUT@', '@INPUT@',
+    command: [test_gircompiler, '-o', '@OUTPUT@', '@INPUT@',
               '--includedir', join_paths(build_root, 'gir'),
               '--includedir', meson.current_build_dir()
     ],
diff --git a/tests/scanner/meson.build b/tests/scanner/meson.build
index fa7f7eca..5176b957 100644
--- a/tests/scanner/meson.build
+++ b/tests/scanner/meson.build
@@ -105,19 +105,19 @@ regress_lib = shared_library('regress-1.0',
 python_path = run_command(python, ['-c', 'import sys; sys.stdout.write(sys.executable)']).stdout()
 
 gircompiler_command = [
-  gircompiler, '-o', '@OUTPUT@', '@INPUT@',
+  test_gircompiler, '-o', '@OUTPUT@', '@INPUT@',
   '--includedir', join_paths(build_root, 'gir'),
   '--includedir', meson.current_build_dir(),
 ]
 
-if glib_dep.type_name() == 'pkgconfig'
+if (glib_dep.type_name() == 'pkgconfig' and
+    get_option('build_introspection_data') == true)
   typedef_gir = custom_target('gir-typedef',
     input: ['typedefs.c', 'typedefs.h'],
     output: 'Typedefs-1.0.gir',
     depends: [typedef_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -156,8 +156,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Bar-1.0.gir',
     depends: [barapp_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -195,8 +194,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'SLetter-1.0.gir',
     depends: [sletter_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -233,8 +231,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'WarnLib-1.0.gir',
     depends: [warnlib_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -269,8 +266,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Utility-1.0.gir',
     depends: [utility_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -307,8 +303,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'GtkFrob-1.0.gir',
     depends: [gtkfrob_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -346,8 +341,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'GetType-1.0.gir',
     depends: [gettype_lib] + typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -384,8 +378,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Symbolfilter-1.0.gir',
     depends: typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -412,8 +405,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Identfilter-1.0.gir',
     depends: typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -441,8 +433,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Headeronly-1.0.gir',
     depends: typelibs,
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -477,8 +468,7 @@ if glib_dep.type_name() == 'pkgconfig'
     output: 'Regress-1.0.gir',
     depends: [regress_lib] + typelibs + [utility_gir],
     command: [
-      python,
-      girscanner,
+      test_girscanner,
       '--quiet',
       '--output=@OUTPUT@',
       '--no-libtool',
@@ -514,6 +504,8 @@ if glib_dep.type_name() == 'pkgconfig'
     command: gircompiler_command,
   )
   test_typelibs += regress_typelib
+else
+  regress_gir = disabler()
 endif
 
 gi_tester = files(join_paths('..', 'gi-tester'))
diff --git a/tools/g-ir-tool-template.in b/tools/g-ir-tool-template.in
index 75bf759c..6e98f52e 100755
--- a/tools/g-ir-tool-template.in
+++ b/tools/g-ir-tool-template.in
@@ -81,7 +81,7 @@ if not os.path.isfile(os.path.join(pylibdir, 'giscanner', '_giscanner' + py_mod_
         builddir = os.path.abspath(os.path.join(filedir, '..'))
         pylibdir = builddir
         builtins.__dict__['GIRDIR'].append(os.path.join(filedir, os.pardir, 'gir'))
-        gdump_path = os.path.join(builddir, 'girepository', 'gdump.c')
+        gdump_path = os.path.join(builddir, 'giscanner', 'gdump.c')
         if os.path.isfile(gdump_path):
             builtins.__dict__['GDUMP_PATH'] = gdump_path
     else:
diff --git a/tools/meson.build b/tools/meson.build
index f272c955..46b487e0 100644
--- a/tools/meson.build
+++ b/tools/meson.build
@@ -30,6 +30,11 @@ foreach tool : tools
     output: tool[0],
     configuration: tools_conf,
     install_dir: get_option('bindir'),
+    # Not yet supported, but put here to document intention.
+    # depends: [
+    #   giscanner_pymod
+    # ],
+    # depend_files: giscanner_built_files,
   )
   tool_output += tool_bin
   # Provide tools for others when we're a subproject and they use the Meson GNOME module
@@ -59,6 +64,7 @@ gircompiler = executable('g-ir-compiler', 'compiler.c',
   install: true,
   c_args: custom_c_args,
 )
+meson.override_find_program('g-ir-compiler', gircompiler)
 
 girgenerate = executable('g-ir-generate', 'generate.c',
   dependencies: [
@@ -68,15 +74,11 @@ girgenerate = executable('g-ir-generate', 'generate.c',
   install: true,
   c_args: custom_c_args,
 )
+meson.override_find_program('g-ir-generate', girgenerate)
 
 girinspect = executable('g-ir-inspect', 'g-ir-inspect.c',
   dependencies: girepo_dep,
   install: true,
   c_args: custom_c_args,
 )
-
-if not get_option('gi_cross_use_prebuilt_gi')
-  meson.override_find_program('g-ir-compiler', gircompiler)
-  meson.override_find_program('g-ir-generate', girgenerate)
-  meson.override_find_program('g-ir-inspect', girinspect)
-endif
+meson.override_find_program('g-ir-inspect', girinspect)