[glib: 2/4] gdbus-codegen: Add --glib-max-allowed argument

[Philip Withnall <pwithnall src gnome org>]

commit 9734e4854ebeaee684d566daa97cb518c4488b0e
Author: Philip Withnall <withnall endlessm com>
Date:   Mon Jan 27 10:36:03 2020 +0000

    gdbus-codegen: Add --glib-max-allowed argument
    
    This complements the `--glib-min-required` argument, just like the
    `GLIB_MIN_REQUIRED` and `GLIB_MAX_ALLOWED` preprocessor defines which
    control access to APIs in C.
    
    Currently, it doesn’t affect code generation at all. When we next change
    code generation, we will need to gate any new API usage on this
    argument.
    
    Signed-off-by: Philip Withnall <withnall endlessm com>
    
    Fixes: #1993

 docs/reference/gio/gdbus-codegen.xml  | 22 +++++++++++++++
 gio/gdbus-2.0/codegen/codegen_main.py | 24 ++++++++++++++++
 gio/gdbus-2.0/codegen/config.py.in    |  2 ++
 gio/gdbus-2.0/codegen/meson.build     |  2 ++
 gio/tests/codegen.py                  | 52 ++++++++++++++++++++++++++++++++++-
 5 files changed, 101 insertions(+), 1 deletion(-)
---
diff --git a/docs/reference/gio/gdbus-codegen.xml b/docs/reference/gio/gdbus-codegen.xml
index 9d62c3757..9687681fd 100644
--- a/docs/reference/gio/gdbus-codegen.xml
+++ b/docs/reference/gio/gdbus-codegen.xml
@@ -51,6 +51,7 @@
       </arg>
     </group>
     <arg><option>--glib-min-required</option> <replaceable>VERSION</replaceable></arg>
+    <arg><option>--glib-max-allowed</option> <replaceable>VERSION</replaceable></arg>
     <arg choice="plain">FILE</arg>
     <arg>
       <arg choice="plain" rep="repeat">FILE</arg>
@@ -460,6 +461,27 @@ gdbus-codegen --c-namespace MyApp                           \
       </listitem>
     </varlistentry>
 
+    <varlistentry>
+      <term><option>--glib-max-allowed</option> <replaceable>VERSION</replaceable></term>
+      <listitem>
+        <para>
+          Specifies the maximum version of GLib which the code generated by
+          <command>gdbus-codegen</command> can depend on. This may be used to
+          ensure that code generated by <command>gdbus-codegen</command> is
+          compilable with specific older versions of GLib that your software has
+          to support.
+        </para>
+        <para>
+          The version number must be of the form
+          
<literal><replaceable>MAJOR</replaceable>.<replaceable>MINOR</replaceable>.<replaceable>MICRO</replaceable></literal>,
+          where all parts are integers. <replaceable>MINOR</replaceable> and
+          <replaceable>MICRO</replaceable> are optional. The version number must
+          be greater than or equal to that passed to <option>--glib-min-required</option>.
+          It defaults to the version of GLib which provides this <command>gdbus-codegen</command>.
+        </para>
+      </listitem>
+    </varlistentry>
+
   </variablelist>
 </refsect1>
 
diff --git a/gio/gdbus-2.0/codegen/codegen_main.py b/gio/gdbus-2.0/codegen/codegen_main.py
index 60e1ae042..c938640e7 100644
--- a/gio/gdbus-2.0/codegen/codegen_main.py
+++ b/gio/gdbus-2.0/codegen/codegen_main.py
@@ -169,6 +169,8 @@ def codegen_main():
                             help='Add annotation (may be used several times)')
     arg_parser.add_argument('--glib-min-required', metavar='VERSION',
                             help='Minimum version of GLib to be supported by the outputted code (default: 
2.30)')
+    arg_parser.add_argument('--glib-max-allowed', metavar='VERSION',
+                            help='Maximum version of GLib to be used by the outputted code (default: current 
GLib version)')
 
     group = arg_parser.add_mutually_exclusive_group()
     group.add_argument('--generate-c-code', metavar='OUTFILES',
@@ -256,6 +258,28 @@ def codegen_main():
     else:
         glib_min_required = (2, 30)
 
+    # And the maximum GLib version.
+    if args.glib_max_allowed:
+        try:
+            parts = args.glib_max_allowed.split('.', 3)
+            glib_max_allowed = (int(parts[0]),
+                                int(parts[1] if len(parts) > 1 else 0))
+            # Ignore micro component, but still validate it:
+            _ = int(parts[2] if len(parts) > 2 else 0)
+        except (ValueError, IndexError):
+            print_error('Unrecognized --glib-max-allowed string ‘{}’'.format(
+                args.glib_max_allowed))
+    else:
+        glib_max_allowed = (config.MAJOR_VERSION, config.MINOR_VERSION)
+
+    # Round --glib-max-allowed up to the next stable release.
+    glib_max_allowed = \
+        (glib_max_allowed[0], glib_max_allowed[1] + (glib_max_allowed[1] % 2))
+
+    if glib_max_allowed < glib_min_required:
+        print_error('Invalid versions: --glib-min-required ({}) must be '
+                    'less than or equal to --glib-max-allowed ({})'.format(glib_min_required, 
glib_max_allowed))
+
     glib_min_required_is_2_64 = (glib_min_required[0] > 2 or
                                  (glib_min_required[0] == 2 and
                                   glib_min_required[1] >= 64))
diff --git a/gio/gdbus-2.0/codegen/config.py.in b/gio/gdbus-2.0/codegen/config.py.in
index a91178a95..4e6df5a09 100644
--- a/gio/gdbus-2.0/codegen/config.py.in
+++ b/gio/gdbus-2.0/codegen/config.py.in
@@ -20,3 +20,5 @@
 # Author: David Zeuthen <davidz redhat com>
 
 VERSION = "@VERSION@"
+MAJOR_VERSION = @MAJOR_VERSION@
+MINOR_VERSION = @MINOR_VERSION@
diff --git a/gio/gdbus-2.0/codegen/meson.build b/gio/gdbus-2.0/codegen/meson.build
index 121e9e6bb..ff5edb977 100644
--- a/gio/gdbus-2.0/codegen/meson.build
+++ b/gio/gdbus-2.0/codegen/meson.build
@@ -10,6 +10,8 @@ gdbus_codegen_files = [
 
 gdbus_codegen_conf = configuration_data()
 gdbus_codegen_conf.set('VERSION', glib_version)
+gdbus_codegen_conf.set('MAJOR_VERSION', major_version)
+gdbus_codegen_conf.set('MINOR_VERSION', minor_version)
 gdbus_codegen_conf.set('PYTHON', python_name)
 gdbus_codegen_conf.set('DATADIR', glib_datadir)
 
diff --git a/gio/tests/codegen.py b/gio/tests/codegen.py
index bbb51117d..51de0ede4 100644
--- a/gio/tests/codegen.py
+++ b/gio/tests/codegen.py
@@ -384,7 +384,8 @@ G_END_DECLS
         result = self.runCodegenWithInterface('',
                                               '--output', '/dev/stdout',
                                               '--header',
-                                              '--glib-min-required', '3')
+                                              '--glib-min-required', '3',
+                                              '--glib-max-allowed', '3.2')
         self.assertEqual('', result.err)
         self.assertNotEqual('', result.out.strip())
 
@@ -397,6 +398,55 @@ G_END_DECLS
         self.assertEqual('', result.err)
         self.assertNotEqual('', result.out.strip())
 
+    def test_glib_max_allowed_too_low(self):
+        """Test running with a --glib-max-allowed which is too low (and hence
+        probably a typo)."""
+        with self.assertRaises(subprocess.CalledProcessError):
+            self.runCodegenWithInterface('',
+                                         '--output', '/dev/stdout',
+                                         '--body',
+                                         '--glib-max-allowed', '2.6')
+
+    def test_glib_max_allowed_major_only(self):
+        """Test running with a --glib-max-allowed which contains only a major version."""
+        result = self.runCodegenWithInterface('',
+                                              '--output', '/dev/stdout',
+                                              '--header',
+                                              '--glib-max-allowed', '3')
+        self.assertEqual('', result.err)
+        self.assertNotEqual('', result.out.strip())
+
+    def test_glib_max_allowed_with_micro(self):
+        """Test running with a --glib-max-allowed which contains a micro version."""
+        result = self.runCodegenWithInterface('',
+                                              '--output', '/dev/stdout',
+                                              '--header',
+                                              '--glib-max-allowed', '2.46.2')
+        self.assertEqual('', result.err)
+        self.assertNotEqual('', result.out.strip())
+
+    def test_glib_max_allowed_unstable(self):
+        """Test running with a --glib-max-allowed which is unstable. It should
+        be rounded up to the next stable version number, and hence should not
+        end up less than --glib-min-required."""
+        result = self.runCodegenWithInterface('',
+                                              '--output', '/dev/stdout',
+                                              '--header',
+                                              '--glib-max-allowed', '2.63',
+                                              '--glib-min-required', '2.64')
+        self.assertEqual('', result.err)
+        self.assertNotEqual('', result.out.strip())
+
+    def test_glib_max_allowed_less_than_min_required(self):
+        """Test running with a --glib-max-allowed which is less than
+        --glib-min-required."""
+        with self.assertRaises(subprocess.CalledProcessError):
+            self.runCodegenWithInterface('',
+                                         '--output', '/dev/stdout',
+                                         '--body',
+                                         '--glib-max-allowed', '2.62',
+                                         '--glib-min-required', '2.64')
+
     def test_unix_fd_types_and_annotations(self):
         """Test an interface with `h` arguments, no annotation, and GLib < 2.64.