From e15e848474a5c180b2f22cd059c44905a11568ef Mon Sep 17 00:00:00 2001
From: Brad Warren <bmw@users.noreply.github.com>
Date: Thu, 2 May 2019 11:36:47 -0700
Subject: [PATCH] Stop certbot-auto from printing blank lines (#7016)

Fixes #7012.

Apparently, the previous test we had here doesn't catch the case when certbot-auto prints blank lines. (I don't yet understand why so if someone does, please let me know!)

Regardless, I fixed up the test and verified it fails with the version of letsencrypt-auto in master and then fixed letsencrypt-auto so the test passes.

I ran test farm tests on the changes here and they passed on all instances.

* correct test

* fixes #7012
---
 letsencrypt-auto-source/letsencrypt-auto                  | 8 +++++---
 letsencrypt-auto-source/letsencrypt-auto.template         | 8 +++++---
 .../scripts/test_letsencrypt_auto_certonly_standalone.sh  | 4 ++--
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/letsencrypt-auto-source/letsencrypt-auto b/letsencrypt-auto-source/letsencrypt-auto
index 4e1503715..f9f02da62 100755
--- a/letsencrypt-auto-source/letsencrypt-auto
+++ b/letsencrypt-auto-source/letsencrypt-auto
@@ -1593,12 +1593,14 @@ UNLIKELY_EOF
     # ---------------------------------------------------------------------------
     # If the script fails for some reason, don't break certbot-auto.
     set +e
-    # Suppress unexpected error output and only print the script's output if it
-    # ran successfully.
+    # Suppress unexpected error output.
     CHECK_PERM_OUT=$("$LE_PYTHON" "$TEMP_DIR/check_permissions.py" "$0" 2>/dev/null)
     CHECK_PERM_STATUS="$?"
     set -e
-    if [ "$CHECK_PERM_STATUS" = 0 ]; then
+    # Only print output if the script ran successfully and it actually produced
+    # output. The latter check resolves
+    # https://github.com/certbot/certbot/issues/7012.
+    if [ "$CHECK_PERM_STATUS" = 0 -a -n "$CHECK_PERM_OUT" ]; then
       error "$CHECK_PERM_OUT"
     fi
   fi
diff --git a/letsencrypt-auto-source/letsencrypt-auto.template b/letsencrypt-auto-source/letsencrypt-auto.template
index 21db0f908..bff4173d4 100755
--- a/letsencrypt-auto-source/letsencrypt-auto.template
+++ b/letsencrypt-auto-source/letsencrypt-auto.template
@@ -670,12 +670,14 @@ UNLIKELY_EOF
     # ---------------------------------------------------------------------------
     # If the script fails for some reason, don't break certbot-auto.
     set +e
-    # Suppress unexpected error output and only print the script's output if it
-    # ran successfully.
+    # Suppress unexpected error output.
     CHECK_PERM_OUT=$("$LE_PYTHON" "$TEMP_DIR/check_permissions.py" "$0" 2>/dev/null)
     CHECK_PERM_STATUS="$?"
     set -e
-    if [ "$CHECK_PERM_STATUS" = 0 ]; then
+    # Only print output if the script ran successfully and it actually produced
+    # output. The latter check resolves
+    # https://github.com/certbot/certbot/issues/7012.
+    if [ "$CHECK_PERM_STATUS" = 0 -a -n "$CHECK_PERM_OUT" ]; then
       error "$CHECK_PERM_OUT"
     fi
   fi
diff --git a/tests/letstest/scripts/test_letsencrypt_auto_certonly_standalone.sh b/tests/letstest/scripts/test_letsencrypt_auto_certonly_standalone.sh
index 035512ef7..0973bbc03 100755
--- a/tests/letstest/scripts/test_letsencrypt_auto_certonly_standalone.sh
+++ b/tests/letstest/scripts/test_letsencrypt_auto_certonly_standalone.sh
@@ -42,8 +42,8 @@ if ! letsencrypt-auto --help --no-self-upgrade | grep -F "letsencrypt-auto [SUBC
     exit 1
 fi
 
-OUTPUT=$(letsencrypt-auto --install-only --no-self-upgrade --quiet 2>&1)
-if [ -n "$OUTPUT" ]; then
+OUTPUT_LEN=$(letsencrypt-auto --install-only --no-self-upgrade --quiet 2>&1 | wc -c)
+if [ "$OUTPUT_LEN" != 0 ]; then
     echo letsencrypt-auto produced unexpected output!
     exit 1
 fi