test-lib: make test_expect_code a test command

Change test_expect_code to be a normal test command instead of a
top-level command.

As a top-level command it would fail in cases like:

    test_expect_code 1 'phoney' '
        foo && bar && (exit 1)
    '

Here the test might incorrectly succeed if "foo" or "bar" happened to
fail with exit status 1. Instead we now do:

    test_expect_success 'phoney' '
        foo && bar && test_expect_code 1 "(exit 1)"
    '

Which will only succeed if "foo" and "bar" return status 0, and "(exit
1)" returns status 1.  Note that test_expect_code has been made slightly
noisier, as it reports the exit code it receives even upon success.

Some test code in t0000-basic.sh relied on the old semantics of
test_expect_code to test the test_when_finished command. I've
converted that code to use an external test similar to the TODO test I
added in v1.7.3-rc0~2^2~3.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t0000-basic.sh

@@ -130,22 +130,57 @@ test_expect_success 'tests clean up after themselves' '
     test_when_finished clean=yes
 '
 
-cleaner=no
-test_expect_code 1 'tests clean up even after a failure' '
-    test_when_finished cleaner=yes &&
-    (exit 1)
-'
-
-if test $clean$cleaner != yesyes
+if test $clean != yes
 then
-	say "bug in test framework: cleanup commands do not work reliably"
+	say "bug in test framework: basic cleanup command does not work reliably"
 	exit 1
 fi
 
-test_expect_code 2 'failure to clean up causes the test to fail' '
-    test_when_finished "(exit 2)"
+test_expect_success 'tests clean up even on failures' "
+    mkdir failing-cleanup &&
+    (cd failing-cleanup &&
+    cat >failing-cleanup.sh <<EOF &&
+#!$SHELL_PATH
+
+test_description='Failing tests with cleanup commands'
+
+# Point to the t/test-lib.sh, which isn't in ../ as usual
+TEST_DIRECTORY=\"$TEST_DIRECTORY\"
+. \"\$TEST_DIRECTORY\"/test-lib.sh
+
+test_expect_success 'tests clean up even after a failure' '
+    touch clean-after-failure &&
+    test_when_finished rm clean-after-failure &&
+    (exit 1)
 '
 
+test_expect_success 'failure to clean up causes the test to fail' '
+    test_when_finished \"(exit 2)\"
+'
+
+test_done
+EOF
+    chmod +x failing-cleanup.sh &&
+    test_must_fail ./failing-cleanup.sh >out 2>err &&
+    ! test -s err &&
+    ! test -f \"trash directory.failing-cleanup/clean-after-failure\" &&
+sed -e 's/Z$//' >expect <<\EOF &&
+not ok - 1 tests clean up even after a failure
+#	Z
+#	    touch clean-after-failure &&
+#	    test_when_finished rm clean-after-failure &&
+#	    (exit 1)
+#	Z
+not ok - 2 failure to clean up causes the test to fail
+#	Z
+#	    test_when_finished \"(exit 2)\"
+#	Z
+# failed 2 among 2 test(s)
+1..2
+EOF
+    test_cmp expect out)
+"
+
 ################################################################
 # Basics of the basics