tests: Check that run_target can find a files() argument

Tests https://github.com/mesonbuild/meson/issues/957

run_unittests.py

@@ -73,6 +73,9 @@ class LinuxlikeTests(unittest.TestCase):
     def build(self):
         self.output += subprocess.check_output(self.ninja_command)
 
+    def run_target(self, target):
+        self.output += subprocess.check_output(self.ninja_command + [target])
+
     def setconf(self, arg):
         self.output += subprocess.check_output(self.mconf_command + [arg, self.builddir])
 
@@ -173,5 +176,10 @@ class LinuxlikeTests(unittest.TestCase):
         self.assertEqual(intro[0]['install_filename'], '/usr/local/libtest/libstat.a')
         self.assertEqual(intro[1]['install_filename'], '/usr/local/bin/prog')
 
+    def test_run_target_files_path(self):
+        testdir = os.path.join(self.common_test_dir, '58 run target')
+        self.init(testdir)
+        self.run_target('check_exists')
+
 if __name__ == '__main__':
     unittest.main()

test cases/common/58 run target/check_exists.py

@@ -0,0 +1,7 @@
+#!/usr/bin/env python
+
+import os
+import sys
+
+if not os.path.isfile(sys.argv[1]):
+    raise Exception("Couldn't find {!r}".format(sys.argv[1]))

test cases/common/58 run target/meson.build

@@ -35,8 +35,8 @@ python3 = find_program('python3')
 run_target('py3hi',
   command : [python3, '-c', 'print("I am Python3.")'])
 
-run_target('ct_in_arg',
-  command : ['echo', hex, files('helloprinter.c')])
+run_target('check_exists',
+  command : [find_program('check_exists.py'), files('helloprinter.c')])
 
 # What if the output of a custom_target is the command to
 # execute. Obviously this will not work as hex is not an