Sane use of test_expect_failure

Originally, test_expect_failure was designed to be the opposite
of test_expect_success, but this was a bad decision.  Most tests
run a series of commands that leads to the single command that
needs to be tested, like this:

    test_expect_{success,failure} 'test title' '
	setup1 &&
        setup2 &&
        setup3 &&
        what is to be tested
    '

And expecting a failure exit from the whole sequence misses the
point of writing tests.  Your setup$N that are supposed to
succeed may have failed without even reaching what you are
trying to test.  The only valid use of test_expect_failure is to
check a trivial single command that is expected to fail, which
is a minority in tests of Porcelain-ish commands.

This large-ish patch rewrites all uses of test_expect_failure to
use test_expect_success and rewrites the condition of what is
tested, like this:

    test_expect_success 'test title' '
	setup1 &&
        setup2 &&
        setup3 &&
        ! this command should fail
    '

test_expect_failure is redefined to serve as a reminder that
that test *should* succeed but due to a known breakage in git it
currently does not pass.  So if git-foo command should create a
file 'bar' but you discovered a bug that it doesn't, you can
write a test like this:

    test_expect_failure 'git-foo should create bar' '
        rm -f bar &&
        git foo &&
        test -f bar
    '

This construct acts similar to test_expect_success, but instead
of reporting "ok/FAIL" like test_expect_success does, the
outcome is reported as "FIXED/still broken".

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 23 insertions, 16 deletions

diff --git a/t/t1300-repo-config.sh b/t/t1300-repo-config.sh
index 42eac2a7c..a786c5c97 100755
--- a/t/t1300-repo-config.sh
+++ b/t/t1300-repo-config.sh
@@ -181,8 +181,9 @@ test_expect_success 'non-match' \
 test_expect_success 'non-match value' \
 	'test wow = $(git config --get nextsection.nonewline !for)'
 
-test_expect_failure 'ambiguous get' \
-	'git config --get nextsection.nonewline'
+test_expect_success 'ambiguous get' '
+	! git config --get nextsection.nonewline
+'
 
 test_expect_success 'get multivar' \
 	'git config --get-all nextsection.nonewline'
@@ -202,13 +203,17 @@ EOF
 
 test_expect_success 'multivar replace' 'cmp .git/config expect'
 
-test_expect_failure 'ambiguous value' 'git config nextsection.nonewline'
+test_expect_success 'ambiguous value' '
+	! git config nextsection.nonewline
+'
 
-test_expect_failure 'ambiguous unset' \
-	'git config --unset nextsection.nonewline'
+test_expect_success 'ambiguous unset' '
+	! git config --unset nextsection.nonewline
+'
 
-test_expect_failure 'invalid unset' \
-	'git config --unset somesection.nonewline'
+test_expect_success 'invalid unset' '
+	! git config --unset somesection.nonewline
+'
 
 git config --unset nextsection.nonewline "wow3$"
 
@@ -224,7 +229,7 @@ EOF
 
 test_expect_success 'multivar unset' 'cmp .git/config expect'
 
-test_expect_failure 'invalid key' 'git config inval.2key blabla'
+test_expect_success 'invalid key' '! git config inval.2key blabla'
 
 test_expect_success 'correct key' 'git config 123456.a123 987'
 
@@ -382,8 +387,9 @@ EOF
 
 test_expect_success "rename succeeded" "git diff expect .git/config"
 
-test_expect_failure "rename non-existing section" \
-	'git config --rename-section branch."world domination" branch.drei'
+test_expect_success "rename non-existing section" '
+	! git config --rename-section branch."world domination" branch.drei
+'
 
 test_expect_success "rename succeeded" "git diff expect .git/config"
 
@@ -494,14 +500,14 @@ test_expect_success bool '
         done &&
 	cmp expect result'
 
-test_expect_failure 'invalid bool (--get)' '
+test_expect_success 'invalid bool (--get)' '
 
 	git config bool.nobool foobar &&
-	git config --bool --get bool.nobool'
+	! git config --bool --get bool.nobool'
 
-test_expect_failure 'invalid bool (set)' '
+test_expect_success 'invalid bool (set)' '
 
-	git config --bool bool.nobool foobar'
+	! git config --bool bool.nobool foobar'
 
 rm .git/config
 
@@ -562,8 +568,9 @@ EOF
 
 test_expect_success 'quoting' 'cmp .git/config expect'
 
-test_expect_failure 'key with newline' 'git config key.with\\\
-newline 123'
+test_expect_success 'key with newline' '
+	! git config "key.with
+newline" 123'
 
 test_expect_success 'value with newline' 'git config key.sub value.with\\\
 newline'