meson: Add a "python" option to make the python to build against configurable

This allows us to build with Python 2 and run tests with it.
This requires the new "python" meson module which was added in 0.46.0 so
bump the required meson version (glib needs a newer one anyway).

Also fixes a small test error under Python 2.

11 files changed, 49 insertions, 21 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 74052943..457b8921 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -5,14 +5,33 @@ cache:
   paths:
     - _ccache/
 
-fedora-x86_64:
+fedora-x86_64-python3:
   stage: build
   image: registry.gitlab.gnome.org/gnome/gobject-introspection:v1
   variables:
     CCACHE_BASEDIR: "${CI_PROJECT_DIR}"
     CCACHE_DIR: "${CI_PROJECT_DIR}/_ccache"
   script:
-    - meson --prefix /usr --libdir /usr/lib64 --buildtype debug -Dcairo=true _build .
+    - meson --prefix /usr --libdir /usr/lib64 --buildtype debug -Dcairo=true -Dpython=python3 _build .
+    - cd _build
+    - ninja
+    - meson test --print-errorlogs --suite=gobject-introspection --no-suite=glib
+  except:
+    - tags
+  artifacts:
+    when: on_failure
+    name: "gi-_${CI_COMMIT_REF_NAME}"
+    paths:
+      - "${CI_PROJECT_DIR}/_build/meson-logs"
+
+fedora-x86_64-python2:
+  stage: build
+  image: registry.gitlab.gnome.org/gnome/gobject-introspection:v1
+  variables:
+    CCACHE_BASEDIR: "${CI_PROJECT_DIR}"
+    CCACHE_DIR: "${CI_PROJECT_DIR}/_ccache"
+  script:
+    - meson --prefix /usr --libdir /usr/lib64 --buildtype debug -Dcairo=true -Dpython=python2 _build .
     - cd _build
     - ninja
     - meson test --print-errorlogs --suite=gobject-introspection --no-suite=glib
diff --git a/.gitlab-ci/Dockerfile b/.gitlab-ci/Dockerfile
index 8b13de05..c232b6c5 100644
--- a/.gitlab-ci/Dockerfile
+++ b/.gitlab-ci/Dockerfile
@@ -36,6 +36,9 @@ RUN dnf -y install \
     python3-mako \
     python3-pip \
     python3-wheel \
+    python2 \
+    python2-devel \
+    python2-mako \
     redhat-rpm-config \
     systemtap-sdt-devel \
     zlib-devel \
diff --git a/.gitlab-ci/test-msys2.sh b/.gitlab-ci/test-msys2.sh
index ef69fe8f..6260ac15 100644
--- a/.gitlab-ci/test-msys2.sh
+++ b/.gitlab-ci/test-msys2.sh
@@ -32,7 +32,10 @@ export CCACHE_DIR="${CCACHE_BASEDIR}/_ccache"
 pip3 install --upgrade --user meson==0.47.1
 export PATH="$HOME/.local/bin:$PATH"
 
-meson --buildtype debug _build
+# FIXME: https://github.com/Alexpux/MINGW-packages/pull/4064
+# Passing the full interpreter path works around the issue
+PYTHON="$(which python3)"
+meson -Dpython="${PYTHON}" --buildtype debug _build
 cd _build
 ninja
 
diff --git a/gir/meson.build b/gir/meson.build
index 4a3b4508..607bbc45 100644
--- a/gir/meson.build
+++ b/gir/meson.build
@@ -38,7 +38,7 @@ girdir = join_paths(get_option('datadir'), 'gir-1.0')
 install_data(gir_files, install_dir: girdir)
 
 scanner_command = [
-  python3,
+  python,
   girscanner,
   '--output=@OUTPUT@',
   '--no-libtool',
@@ -93,7 +93,7 @@ if dep_type == 'pkgconfig'
     glib_files += join_paths(glib_incdir, 'glib-unix.h')
   endif
   # Parse glob to get installed header list
-  ret = run_command(python3, '-c', globber.format(join_paths(glib_incdir, 'glib', '*.h')))
+  ret = run_command(python, '-c', globber.format(join_paths(glib_incdir, 'glib', '*.h')))
   if ret.returncode() != 0
     error('Failed to get glib header list')
   endif
@@ -101,7 +101,7 @@ if dep_type == 'pkgconfig'
   # Get a list of all source files
   glib_srcdir = get_option('glib-src-dir')
   if glib_srcdir != ''
-    ret = run_command(python3, '-c', globber.format(join_paths(glib_srcdir, 'glib', '*.c')))
+    ret = run_command(python, '-c', globber.format(join_paths(glib_srcdir, 'glib', '*.c')))
     if ret.returncode() != 0
       error('Failed to get glib source list')
     endif
@@ -200,13 +200,13 @@ gobject_command = scanner_command + [
 if dep_type == 'pkgconfig'
   gobject_command += ['--external-library', '--pkg=gobject-2.0']
   # Get the installed header list
-  ret = run_command(python3, '-c', globber.format(join_paths(glib_incdir, 'gobject', '*.h')))
+  ret = run_command(python, '-c', globber.format(join_paths(glib_incdir, 'gobject', '*.h')))
   if ret.returncode() != 0
     error('Failed to get gobject header list')
   endif
   gobject_headers = ret.stdout().strip().split('\n')
   if glib_srcdir != ''
-    ret = run_command(python3, '-c', globber.format(join_paths(glib_srcdir, 'gobject', '*.c')))
+    ret = run_command(python, '-c', globber.format(join_paths(glib_srcdir, 'gobject', '*.c')))
     if ret.returncode() != 0
       error('Failed to get gobject source list')
     endif
@@ -307,7 +307,7 @@ gio_command = scanner_command + [
 if dep_type == 'pkgconfig'
   gio_command += ['--external-library', '--pkg=gio-2.0']
   # Get the installed header list
-  ret = run_command(python3, '-c', globber.format(join_paths(glib_incdir, 'gio', '*.h')))
+  ret = run_command(python, '-c', globber.format(join_paths(glib_incdir, 'gio', '*.h')))
   if ret.returncode() != 0
     error('Failed to get gio header list')
   endif
@@ -316,7 +316,7 @@ if dep_type == 'pkgconfig'
   # probably fine since it matches what Autotools does. We are more exact in
   # the subproject case.
   if glib_srcdir != ''
-    ret = run_command(python3, '-c', globber.format(join_paths(glib_srcdir, 'gio', '*.c')))
+    ret = run_command(python, '-c', globber.format(join_paths(glib_srcdir, 'gio', '*.c')))
     if ret.returncode() != 0
       error('Failed to get gio source list')
     endif
@@ -341,7 +341,7 @@ if giounix_dep.found()
     gio_command += ['--pkg=gio-unix-2.0']
     giounix_includedir = join_paths(giounix_dep.get_pkgconfig_variable('includedir'), 'gio-unix-2.0')
     # Get the installed gio-unix header list
-    ret = run_command(python3, '-c', globber.format(join_paths(giounix_includedir, 'gio', '*.h')))
+    ret = run_command(python, '-c', globber.format(join_paths(giounix_includedir, 'gio', '*.h')))
     if ret.returncode() != 0
       error('Failed to get gio-unix header list')
     endif
diff --git a/giscanner/introspectablepass.py b/giscanner/introspectablepass.py
index 19d1388f..072494bd 100644
--- a/giscanner/introspectablepass.py
+++ b/giscanner/introspectablepass.py
@@ -84,7 +84,7 @@ class IntrospectablePass(object):
 
         if not node.type.resolved:
             self._parameter_warning(parent, node,
-                                    "Unresolved type: %r" % (node.type.unresolved_string, ))
+                                    "Unresolved type: '%s'" % (node.type.unresolved_string, ))
             parent.introspectable = False
             return
 
diff --git a/giscanner/meson.build b/giscanner/meson.build
index 5a1e44c9..b4ec3796 100644
--- a/giscanner/meson.build
+++ b/giscanner/meson.build
@@ -79,12 +79,12 @@ giscanner_lib = static_library('giscanner',
   dependencies: [glib_dep, gobject_dep, gio_dep, gmodule_dep],
 )
 
-giscanner_pymod = py3.extension_module('_giscanner', 'giscannermodule.c',
+giscanner_pymod = python.extension_module('_giscanner', ['giscannermodule.c'],
   link_with: giscanner_lib,
   c_args: [gi_hidden_visibility_cflags],
   include_directories : configinc,
   dependencies: [glib_dep, gobject_dep, gio_dep, gmodule_dep,
-                 dependency('python3')],
+                 python.dependency()],
   install: true,
   install_dir: giscannerdir,
 )
diff --git a/meson.build b/meson.build
index 07446553..f5d7561a 100644
--- a/meson.build
+++ b/meson.build
@@ -1,6 +1,6 @@
 project('gobject-introspection', 'c',
   version: '1.57.1',
-  meson_version: '>= 0.42.0',
+  meson_version: '>= 0.46.0',
   default_options: [
     'warning_level=1',
     'buildtype=debugoptimized',
@@ -12,8 +12,8 @@ gi_versions = meson.project_version().split('.')
 
 configinc = include_directories('.')
 
-py3 = import('python3')
-python3 = py3.find_python()
+pymod = import('python')
+python = pymod.find_installation(get_option('python'))
 
 cc = meson.get_compiler('c')
 config = configuration_data()
diff --git a/meson_options.txt b/meson_options.txt
index 28244208..49726be6 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -17,3 +17,7 @@ option('gtk-doc', type: 'boolean', value: false,
 option('cairo-libname', type: 'string',
   description: 'Custom name for the cairo-gobject library name'
 )
+
+option('python', type: 'string', value: 'python3',
+  description: 'Path or name of the Python interpreter to build for'
+)
diff --git a/tests/scanner/meson.build b/tests/scanner/meson.build
index cd8df991..e64345a0 100644
--- a/tests/scanner/meson.build
+++ b/tests/scanner/meson.build
@@ -13,6 +13,6 @@ if host_system != 'windows'
 endif
 
 foreach f : scanner_test_files 
-  test(f, python3, args: files(f), env: scanner_test_env)
+  test(f, python, args: files(f), env: scanner_test_env)
 endforeach
 
diff --git a/tests/warn/meson.build b/tests/warn/meson.build
index 53d00cc7..f14590ca 100644
--- a/tests/warn/meson.build
+++ b/tests/warn/meson.build
@@ -32,7 +32,7 @@ warn_test_env.set(
 if host_system != 'windows'
   foreach warn_fn : warn_tests
     test(
-      'warn-' + warn_fn.split('.')[0], files(python3.path()),
+      'warn-' + warn_fn.split('.')[0], python,
       workdir: meson.current_source_dir(),
       env: warn_test_env,
       args: ['warningtester.py', warn_fn],
diff --git a/tools/meson.build b/tools/meson.build
index 8971a9d5..aaf4bc84 100644
--- a/tools/meson.build
+++ b/tools/meson.build
@@ -1,6 +1,5 @@
 libdir_abs = join_paths(get_option('prefix'), get_option('libdir'))
 datadir_abs = join_paths(get_option('prefix'), get_option('datadir'))
-python_path = python3.path()
 
 tools = [
   ['g-ir-scanner', 'scannermain', 'scanner_main'],
@@ -15,7 +14,7 @@ foreach tool : tools
   tools_conf = configuration_data()
   tools_conf.set('libdir', libdir_abs)
   tools_conf.set('datarootdir', datadir_abs)
-  tools_conf.set('PYTHON', python_path)
+  tools_conf.set('PYTHON', 'python' + python.language_version())
 
   tools_conf.set('TOOL_MODULE', tool[1])
   tools_conf.set('TOOL_FUNCTION', tool[2])