Add check on build system version

Since we're shipping both Meson and Autotools build systems for GTK3,
and both of them have a version field, it's bound to happen that the
GTK version defined in either build systems will go out of sync.

Let's add a check in both builds so that something will fail before
doing a release in case the versions do not match.

3 files changed, 170 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
index a044e090dc..9a63602658 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -84,6 +84,7 @@ DISTCLEANFILES = \
 dist-hook:
 	mkdir $(distdir)/subprojects
 	cp -p $(srcdir)/subprojects/*.wrap $(distdir)/subprojects
+	$(top_srcdir)/check-version.py $(top_srcdir)/configure.ac $(top_srcdir)/meson.build
 
 distclean-local:
 	if test "$(srcdir)" = "."; then :; else \
diff --git a/check-version.py b/check-version.py
new file mode 100755
index 0000000000..204a4f6049
--- /dev/null
+++ b/check-version.py
@@ -0,0 +1,159 @@
+#!/usr/bin/env python3
+
+import re
+import sys
+
+try:
+    configure_ac = sys.argv[1]
+except Exception:
+    configure_ac = 'configure.ac'
+
+try:
+    meson_build = sys.argv[2]
+except Exception:
+    meson_build = 'meson.build'
+
+CONFIGURE_MAJOR_VERSION_RE = re.compile(
+    r'''
+    ^
+    \s*
+    m4_define\(
+    \s*
+    \[gtk_major_version\]
+    \s*
+    ,
+    \s*
+    \[
+    (?P<version>[0-9]+)
+    \]
+    \s*
+    \)
+    $
+    ''',
+    re.UNICODE | re.VERBOSE
+)
+
+CONFIGURE_MINOR_VERSION_RE = re.compile(
+    r'''
+    ^
+    \s*
+    m4_define\(
+    \s*
+    \[gtk_minor_version\]
+    \s*
+    ,
+    \s*
+    \[
+    (?P<version>[0-9]+)
+    \]
+    \s*
+    \)
+    $
+    ''',
+    re.UNICODE | re.VERBOSE
+)
+
+CONFIGURE_MICRO_VERSION_RE = re.compile(
+    r'''
+    ^
+    \s*
+    m4_define\(
+    \s*
+    \[gtk_micro_version\]
+    \s*
+    ,
+    \s*
+    \[
+    (?P<version>[0-9]+)
+    \]
+    \s*
+    \)
+    $
+    ''',
+    re.UNICODE | re.VERBOSE
+)
+
+MESON_VERSION_RE = re.compile(
+    r'''
+    ^
+    \s*
+    version
+    \s*
+    :{1}
+    \s*
+    \'{1}
+    (?P<major>[0-9]+)
+    \.{1}
+    (?P<minor>[0-9]+)
+    \.{1}
+    (?P<micro>[0-9]+)
+    \'{1}
+    \s*
+    ,?
+    $
+    ''',
+    re.UNICODE | re.VERBOSE
+)
+
+version = {}
+
+with open(configure_ac, 'r') as f:
+    line = f.readline()
+    while line:
+        res = CONFIGURE_MAJOR_VERSION_RE.match(line)
+        if res:
+            if 'major' in version:
+                print(f'Redefinition of major version; version is already set to {version["major"]}')
+                sys.exit(1)
+            version['major'] = res.group('version')
+            line = f.readline()
+            continue
+        res = CONFIGURE_MINOR_VERSION_RE.match(line)
+        if res:
+            if 'minor' in version:
+                print(f'Redefinition of minor version; version is already set to {version["minor"]}')
+                sys.exit(1)
+            version['minor'] = res.group('version')
+            line = f.readline()
+            continue
+        res = CONFIGURE_MICRO_VERSION_RE.match(line)
+        if res:
+            if 'micro' in version:
+                print(f'Redefinition of micro version; version is already set to {version["micro"]}')
+                sys.exit(1)
+            version['micro'] = res.group('version')
+            line = f.readline()
+            continue
+        if ('major', 'minor', 'micro') in version:
+            break
+        line = f.readline()
+
+print(f'GTK version defined in {configure_ac}: {version["major"]}.{version["minor"]}.{version["micro"]}')
+
+configure_version = version
+version = {}
+
+with open(meson_build, 'r') as f:
+    line = f.readline()
+    inside_project = False
+    while line:
+        if line.startswith('project('):
+            inside_project = True
+        elif inside_project:
+            res = MESON_VERSION_RE.match(line)
+            if res:
+                version['major'] = res.group('major')
+                version['minor'] = res.group('minor')
+                version['micro'] = res.group('micro')
+                break
+        line = f.readline()
+
+print(f'GTK version defined in {meson_build}: {version["major"]}.{version["minor"]}.{version["micro"]}')
+
+meson_version = version
+
+if configure_version != meson_version:
+    print('Version mismatch between Autotools and Meson builds')
+    sys.exit(1)
+
+sys.exit(0)
diff --git a/meson.build b/meson.build
index 7ec6a9e409..dc3f93c5d4 100644
--- a/meson.build
+++ b/meson.build
@@ -987,6 +987,16 @@ if host_machine.system() != 'windows'
     install_dir : join_paths(gtk_datadir, 'gtk-3.0', 'valgrind'))
 endif
 
+test(
+  'version-check',
+  find_program('check-version.py'),
+  args: [
+    join_paths(meson.current_source_dir(), 'configure.ac'),
+    join_paths(meson.current_source_dir(), 'meson.build'),
+  ],
+  suite: 'gtk',
+)
+
 summary = [
   '',
   '------',