MDL-66322 travis: Configure a local copy of 'exttests'

.travis.yml

@@ -13,6 +13,9 @@ language: php
 
 dist: trusty
 
+services:
+    - docker
+
 php:
     # We only run the highest and lowest supported versions to reduce the load on travis-ci.org.
     - 7.2
@@ -72,6 +75,9 @@ cache:
       - $HOME/.composer/cache
       - $HOME/.npm
 
+before_install:
+    - docker run -d -p 127.0.0.1:8080:80 --name exttests moodlehq/moodle-exttests
+
 install:
     - >
         if [ "$DB" = 'mysqli' ];
@@ -181,6 +187,10 @@ before_script:
           -e "/require_once/i \\\$CFG->phpunit_dataroot = '\/home\/travis\/roots\/phpunit';" \
           -e "/require_once/i \\\$CFG->phpunit_prefix = 'p_';" \
           config.php ;
+        # Enable test external resources
+        sed -i \
+          -e "/require_once/i \\define('TEST_EXTERNAL_FILES_HTTP_URL', 'http://127.0.0.1:8080');" \
+          config.php ;
 
         # Initialise PHPUnit for Moodle.
         php admin/tool/phpunit/cli/init.php
@@ -251,6 +261,8 @@ script:
       if [ "$TASK" = 'PHPUNIT' ];
       then
         vendor/bin/phpunit --fail-on-risky --disallow-test-output --verbose;
+        EXTTESTS_HITS=$(docker logs exttests 2>&1 | grep -Fv -e 'AH00558' -e '[pid 1]' | wc -l)
+        echo -e "\nTest local resources number of hits: ${EXTTESTS_HITS}.\n"
       fi
 
     - >