test-lib: introduce test_line_count to measure files
Some tests check their output with code like the following:
test "$(git ls-files -u B | wc -l)" -eq 3 || {
echo "BAD: should have left stages for B"
return 1
}
The verbose failure condition is used because test, unlike
diff, does not print any useful information about the
nature of the failure when it fails.
Introduce a test_line_count function to help. If used like
git ls-files -u B >output &&
test_line_count -eq 3 output
it will produce output like
test_line_count: line count for output !-eq 3
100644 b023018cabc396e7692c70bbf5784a93d3f738ab 2 hi.c
100644 45b983be36b73c0788dc9cbcb76cbb80fc7bb057 3 hi.c
on failure.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 87308f5..a417bdf 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -598,6 +598,28 @@
fi
}
+# test_line_count checks that a file has the number of lines it
+# ought to. For example:
+#
+# test_expect_success 'produce exactly one line of output' '
+# do something >output &&
+# test_line_count = 1 output
+# '
+#
+# is like "test $(wc -l <output) = 1" except that it passes the
+# output through when the number of lines is wrong.
+
+test_line_count () {
+ if test $# != 3
+ then
+ error "bug in the test script: not 3 parameters to test_line_count"
+ elif ! test $(wc -l <"$3") "$1" "$2"
+ then
+ echo "test_line_count: line count for $3 !$1 $2"
+ cat "$3"
+ return 1
+ fi
+}
# This is not among top-level (test_expect_success | test_expect_failure)
# but is a prefix that can be used in the test script, like:
