Rename CHANGED_PWD to CHANGED_PASSWORD.

It's better to know the meaning.

Author: junaruga

.travis_setup.sh

@@ -2,23 +2,24 @@
 
 set -eux
 
-CHANGED_PWD=false
-# Change the password recreating the root user on mariadb < 10.2
+# Change the password to be empty.
+CHANGED_PASSWORD=false
+# Change the password to be empty, recreating the root user on mariadb < 10.2
 # where ALTER USER is not available.
 # https://stackoverflow.com/questions/56052177/
-CHANGED_PWD_BY_RECREATE=false
+CHANGED_PASSWORD_BY_RECREATE=false
 
 # Install the default used DB if DB is not set.
 if [[ -n ${GITHUB_ACTIONS-} && -z ${DB-} ]]; then
   if command -v lsb_release > /dev/null; then
     case "$(lsb_release -cs)" in
     xenial | bionic)
       sudo apt-get install -qq mysql-server-5.7 mysql-client-core-5.7 mysql-client-5.7
-      CHANGED_PWD=true
+      CHANGED_PASSWORD=true
       ;;
     focal)
       sudo apt-get install -qq mysql-server-8.0 mysql-client-core-8.0 mysql-client-8.0
-      CHANGED_PWD=true
+      CHANGED_PASSWORD=true
       ;;
     *)
       ;;
@@ -34,20 +35,20 @@ fi
 # Install MySQL 5.7 if DB=mysql57
 if [[ -n ${DB-} && x$DB =~ ^xmysql57 ]]; then
   sudo bash .travis_mysql57.sh
-  CHANGED_PWD=true
+  CHANGED_PASSWORD=true
 fi
 
 # Install MySQL 8.0 if DB=mysql80
 if [[ -n ${DB-} && x$DB =~ ^xmysql80 ]]; then
   sudo bash .travis_mysql80.sh
-  CHANGED_PWD=true
+  CHANGED_PASSWORD=true
 fi
 
 # Install MariaDB client headers after Travis CI fix for MariaDB 10.2 broke earlier 10.x
 if [[ -n ${DB-} && x$DB =~ ^xmariadb10.0 ]]; then
   if [[ -n ${GITHUB_ACTIONS-} ]]; then
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' mariadb-server mariadb-server-10.0 libmariadb2
-    CHANGED_PWD_BY_RECREATE=true
+    CHANGED_PASSWORD_BY_RECREATE=true
   else
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' libmariadbclient-dev
   fi
@@ -57,7 +58,7 @@ fi
 if [[ -n ${DB-} && x$DB =~ ^xmariadb10.1 ]]; then
   if [[ -n ${GITHUB_ACTIONS-} ]]; then
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' mariadb-server mariadb-server-10.1 libmariadb-dev
-    CHANGED_PWD_BY_RECREATE=true
+    CHANGED_PASSWORD_BY_RECREATE=true
   else
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' libmariadbclient-dev
   fi
@@ -72,7 +73,7 @@ fi
 # Install MariaDB 10.3 if DB=mariadb10.3
 if [[ -n ${GITHUB_ACTIONS-} && -n ${DB-} && x$DB =~ ^xmariadb10.3 ]]; then
   sudo apt-get install -y -o Dpkg::Options::='--force-confnew' mariadb-server mariadb-server-10.3 libmariadb-dev
-  CHANGED_PWD=true
+  CHANGED_PASSWORD=true
 fi
 
 # Install MySQL if OS=darwin
@@ -111,11 +112,11 @@ else
     DB_SYS_USER=root
   fi
 
-  if [ "${CHANGED_PWD}" = true ]; then
+  if [ "${CHANGED_PASSWORD}" = true ]; then
     # https://www.percona.com/blog/2016/03/16/change-user-password-in-mysql-5-7-with-plugin-auth_socket/
     sudo mysql ${MYSQL_OPTS} -u "${DB_SYS_USER}" \
       -e "ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY ''"
-  elif [ "${CHANGED_PWD_BY_RECREATE}" = true ]; then
+  elif [ "${CHANGED_PASSWORD_BY_RECREATE}" = true ]; then
     sudo mysql ${MYSQL_OPTS} -u "${DB_SYS_USER}" <<SQL
 DROP USER 'root'@'localhost';
 CREATE USER 'root'@'localhost' IDENTIFIED BY '';