t5536: simplify checking of messages output to stderr

Commit 2071e05ed2 ("t5536: new test of refspec conflicts when
fetching", 2013-10-30), introduced the verify_stderr() function
which was used to verify that certain fatal/warning messages were
issued by a given git command. In addition, verify_stderr() would
filter a specific "fatal: The remote end hung up unexpectedly"
message, which may, or may not, be present (depending on the
relative timing of the git-fetch and git-upload-pack processes).

The verify_stderr() function has seen several modifications, which
has introduced a couple of minor problems. For example, commit
1edbaac3bb ("tests: use test_i18n* functions to suppress false
positives", 2016-06-17) introduced an inappropriate test_i18ngrep
call and commit f096e6e826 ("fetch: improve the error messages
emitted for conflicting refspecs", 2013-10-30) included an
ineffective invocation of sort at the end of a grep pipeline.

Instead of fixing these minor problems in verify_stderr(), we take
the simpler approach of directly searching the error file, using
test_i18ngrep, for the specific message(s) we expect. (The only
minor downside is that we would not notice any new messages).

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5536-fetch-conflicts.sh

@@ -18,14 +18,6 @@ setup_repository () {
 	)
 }
 
-verify_stderr () {
-	cat >expected &&
-	# We're not interested in the error
-	# "fatal: The remote end hung up unexpectedly":
-	test_i18ngrep -E '^(fatal|warning):' <error | grep -v 'hung up' >actual | sort &&
-	test_i18ncmp expected actual
-}
-
 test_expect_success 'setup' '
 	git commit --allow-empty -m "Initial" &&
 	git branch branch1 &&
@@ -48,9 +40,7 @@ test_expect_success 'fetch conflict: config vs. config' '
 		"+refs/heads/branch2:refs/remotes/origin/branch1" && (
 		cd ccc &&
 		test_must_fail git fetch origin 2>error &&
-		verify_stderr <<-\EOF
-		fatal: Cannot fetch both refs/heads/branch1 and refs/heads/branch2 to refs/remotes/origin/branch1
-		EOF
+		test_i18ngrep "fatal: Cannot fetch both refs/heads/branch1 and refs/heads/branch2 to refs/remotes/origin/branch1" error
 	)
 '
 
@@ -77,9 +67,7 @@ test_expect_success 'fetch conflict: arg vs. arg' '
 		test_must_fail git fetch origin \
 			refs/heads/*:refs/remotes/origin/* \
 			refs/heads/branch2:refs/remotes/origin/branch1 2>error &&
-		verify_stderr <<-\EOF
-		fatal: Cannot fetch both refs/heads/branch1 and refs/heads/branch2 to refs/remotes/origin/branch1
-		EOF
+		test_i18ngrep "fatal: Cannot fetch both refs/heads/branch1 and refs/heads/branch2 to refs/remotes/origin/branch1" error
 	)
 '
 
@@ -90,10 +78,8 @@ test_expect_success 'fetch conflict: criss-cross args' '
 		git fetch origin \
 			refs/heads/branch1:refs/remotes/origin/branch2 \
 			refs/heads/branch2:refs/remotes/origin/branch1 2>error &&
-		verify_stderr <<-\EOF
-		warning: refs/remotes/origin/branch1 usually tracks refs/heads/branch1, not refs/heads/branch2
-		warning: refs/remotes/origin/branch2 usually tracks refs/heads/branch2, not refs/heads/branch1
-		EOF
+		test_i18ngrep "warning: refs/remotes/origin/branch1 usually tracks refs/heads/branch1, not refs/heads/branch2" error &&
+		test_i18ngrep "warning: refs/remotes/origin/branch2 usually tracks refs/heads/branch2, not refs/heads/branch1" error
 	)
 '