Passing --default-library=both should override project value

Looks like this has always been broken, had_argument_for() was checking
if we have --default_library instead of --default-library.

mesonbuild/environment.py

@@ -373,7 +373,7 @@ class Environment:
         return is_library(fname)
 
     def had_argument_for(self, option):
-        trial1 = '--' + option
+        trial1 = coredata.get_builtin_option_cmdline_name(option)
         trial2 = '-D' + option
         previous_is_plaind = False
         for i in self.original_cmd_line_args:

run_unittests.py

@@ -2026,6 +2026,7 @@ recommended as it can lead to undefined behaviour on some platforms''')
         # Verify default values when passing no args
         self.init(testdir)
         obj = mesonbuild.coredata.load(self.builddir)
+        self.assertEqual(obj.builtins['default_library'].value, 'static')
         self.assertEqual(obj.builtins['warning_level'].value, '1')
         self.wipe()
 
@@ -2059,6 +2060,15 @@ recommended as it can lead to undefined behaviour on some platforms''')
             self.assertIn('passed as both', e.stderr)
         self.wipe()
 
+        # --default-library should override default value from project()
+        self.init(testdir, extra_args=['--default-library=both'])
+        obj = mesonbuild.coredata.load(self.builddir)
+        self.assertEqual(obj.builtins['default_library'].value, 'both')
+        self.setconf('--default-library=shared')
+        obj = mesonbuild.coredata.load(self.builddir)
+        self.assertEqual(obj.builtins['default_library'].value, 'shared')
+        self.wipe()
+
 
 class FailureTests(BasePlatformTests):
     '''

test cases/unit/30 command line/meson.build

@@ -1 +1,3 @@
-project('command line test', 'c')
+project('command line test', 'c',
+  default_options : ['default_library=static']
+)