Test PHP 7.3, 7.4, 8.x

Author: paragonie-security

.travis.yml

@@ -1,13 +1,18 @@
 language: php
 sudo: false
 
-php:
-    - "7.0"
-    - "7.1"
-    - "7.2"
-
 matrix:
-    fast_finish: true
+  fast_finish: true
+  include:
+    - php: "7.0"
+    - php: "7.1"
+    - php: "7.2"
+    - php: "7.3"
+    - php: "7.4snapshot"
+    - php: "nightly"
+  allow_failures:
+    - php: "nightly"
+    - php: "7.4snapshot"
 
 install:
     - composer self-update