oeqa: rationalise Perl tests

As with the Python test, this can be both better and faster.  No need to copy a
file, just run a one-liner.

(From OE-Core rev: c6eef46747fe58bb2310be4f06d2fa9b67901d72)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/runtime/cases/perl.py

@@ -1,37 +1,13 @@
 import os
 
 from oeqa.runtime.case import OERuntimeTestCase
-from oeqa.core.decorator.depends import OETestDepends
 from oeqa.core.decorator.oeid import OETestID
 from oeqa.runtime.decorator.package import OEHasPackage
 
 class PerlTest(OERuntimeTestCase):
-
-    @classmethod
-    def setUpClass(cls):
-        src = os.path.join(cls.tc.files_dir, 'test.pl')
-        dst = '/tmp/test.pl'
-        cls.tc.target.copyTo(src, dst)
-
-    @classmethod
-    def tearDownClass(cls):
-        dst = '/tmp/test.pl'
-        cls.tc.target.run('rm %s' % dst)
-
-    @OETestID(1141)
-    @OETestDepends(['ssh.SSHTest.test_ssh'])
-    @OEHasPackage(['perl'])
-    def test_perl_exists(self):
-        status, output = self.target.run('which perl')
-        msg = 'Perl binary not in PATH or not on target.'
-        self.assertEqual(status, 0, msg=msg)
-
     @OETestID(208)
-    @OETestDepends(['perl.PerlTest.test_perl_exists'])
+    @OEHasPackage(['perl'])
     def test_perl_works(self):
-        status, output = self.target.run('perl /tmp/test.pl')
-        msg = 'Exit status was not 0. Output: %s' % output
-        self.assertEqual(status, 0, msg=msg)
-
-        msg = 'Incorrect output: %s' % output
-        self.assertEqual(output, "the value of a is 0.01", msg=msg)
+        status, output = self.target.run("perl -e '$_=\"Uryyb, jbeyq\"; tr/a-zA-Z/n-za-mN-ZA-M/;print'")
+        self.assertEqual(status, 0)
+        self.assertEqual(output, "Hello, world")