coredata: Passing an option is supposed to set it, not flip the default

With the current logic passing `--debug` will actually be parsed as
`-Ddebug=false`, which is absolutely not what is expected.

There is no case in which the presence of a boolean option in `--foo`
form will mean 'I want feature foo disabled', regardless of the
*default* value of that option.

Also includes a test.

Closes https://github.com/mesonbuild/meson/issues/4686

1 files changed, 8 insertions, 0 deletions

diff --git a/run_unittests.py b/run_unittests.py
index 5b25b6c..41e8ad4 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -3842,6 +3842,14 @@ recommended as it is not supported on some platforms''')
         self.assertEqual(opts['debug'], True)
         self.assertEqual(opts['optimization'], '2')
         self.assertEqual(opts['buildtype'], 'debugoptimized')
+        # Setting both buildtype and debug on the command-line should work
+        # Also test that --debug is parsed as -Ddebug=true
+        self.new_builddir()
+        self.init(testdir, extra_args=['-Dbuildtype=debugoptimized', '--debug'])
+        opts = self.get_opts_as_dict()
+        self.assertEqual(opts['debug'], True)
+        self.assertEqual(opts['optimization'], '2')
+        self.assertEqual(opts['buildtype'], 'debugoptimized')
 
     @skipIfNoPkgconfig
     @unittest.skipIf(is_windows(), 'Help needed with fixing this test on windows')