[CI][C++] Remove useless test-file-cleanup step

[pitrou]

Describe the enhancement requested

We have a test file cleanup in run-test.sh that calls find twice with the same parameters, computes the difference and tries to delete files only in the second result. But nothing happens between the two find calls: the results should always be the same (except if there's a race condition).

Since this code isn't doing anything useful, and it doesn't seem to cause any problem, we should just remove it.

arrow/cpp/build-support/run-test.sh

Lines 195 to 222 in e9ec94b

	if [ "$ATTEMPT_NUMBER" -lt "$TEST_EXECUTION_ATTEMPTS" ]; then
	# If the test fails, the test output may or may not be left behind,
	# depending on whether the test cleaned up or exited immediately. Either
	# way we need to clean it up. We do this by comparing the data directory
	# contents before and after the test runs, and deleting anything new.
	#
	# The comm program requires that its two inputs be sorted.
	TEST_TMPDIR_BEFORE=$(find "$TEST_TMPDIR" -maxdepth 1 -type d | sort)
	fi
	if [ "$ATTEMPT_NUMBER" -lt "$TEST_EXECUTION_ATTEMPTS" ]; then
	# Now delete any new test output.
	TEST_TMPDIR_AFTER=$(find "$TEST_TMPDIR" -maxdepth 1 -type d | sort)
	DIFF=$(comm -13 <(echo "$TEST_TMPDIR_BEFORE") \
	<(echo "$TEST_TMPDIR_AFTER"))
	for DIR in $DIFF; do
	# Multiple tests may be running concurrently. To avoid deleting the
	# wrong directories, constrain to only directories beginning with the
	# test name.
	#
	# This may delete old test directories belonging to this test, but
	# that's not typically a concern when rerunning flaky tests.
	if [[ $DIR =~ ^$TEST_TMPDIR/$TEST_NAME ]]; then
	echo Deleting leftover flaky test directory "$DIR"
	rm -Rf "$DIR"
	fi
	done
	fi

Component(s)

C++, Continuous Integration

[pitrou]

@kou @hiroyuki-sato Opinions?

[pitrou]

Also, $TEST_TMPDIR doesn't seem to be defined...

[Diveyam-Mishra]

Seems like a very straight up solution Would like to take this up as my first issue in this repo ?

[pitrou]

@Diveyam-Mishra Definitely, but I would like to wait for @kou 's opinion before we do this.

[kou]

Good catch. It seems that this was introduced by GH-29.

We can remove the retry feature entirely from this script because we can use the CTest's retry feature.

@Diveyam-Mishra Could you add "take" only comment here to assign this issue to you?

[Diveyam-Mishra]

take

[kou]

Issue resolved by pull request 51110
#51110