Use modern Yarn version on Travis CI

Travis CI uses a quite old version of Yarn by default. This adds Yarn's recommended incantation for using the latest stable version.
krombel · Mar 13, 2019 · cd75848 · cd75848
1 parent 1bae15e
commit cd75848
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/.travis.yml b/.travis.yml
@@ -1,5 +1,8 @@
 language: node_js
 node_js:
     - "10.11.0"
+before_install:
+    - curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.13.0
+    - export PATH=$HOME/.yarn/bin:$PATH
 script:
     - ./travis.sh