Can set headers() with variables.

interpreter.py

@@ -1136,6 +1136,7 @@ class Interpreter():
         mlog.debug('Adding test "', mlog.bold(args[0]), '".', sep='')
 
     def func_headers(self, node, args, kwargs):
+        args = self.flatten(args)
         for a in args:
             if not isinstance(a, str):
                 raise InvalidArguments('Argument %s is not a string.' % str(a))

test cases/common/9 header install/meson.build

@@ -1,4 +1,6 @@
 project('header install', 'c')
 
+as_array = ['subdir.h']
+
 h1 = headers('rootdir.h')
-h2 = headers('subdir.h', subdir : 'subdir')
+h2 = headers(as_array, subdir : 'subdir')