Fix travis build (#716)

.travis.yml

@@ -9,21 +9,26 @@ env:
     - MIX_ENV=test
     - HEXPM_PATH=..
     - HEXWEB_PATH=..
+    - HEX_ELIXIR=v1.6.6
+    - HEX_ELIXIR_PATH=hex_elixir
   matrix:
     - HEX_VERSION=master
-    - HEX_VERSION=v0.17.7
+    - HEX_VERSION=v0.18.1
+    - HEX_VERSION=v0.17.8
     - HEX_VERSION=v0.16.1
     - HEX_VERSION=v0.15.0
     - HEX_VERSION=v0.14.1
+before_install:
+  - wget https://repo.hex.pm/builds/elixir/${HEX_ELIXIR}.zip
+  - unzip -d hex_elixir ${HEX_ELIXIR}.zip
 before_script:
   - git clone https://github.com/hexpm/hex hex -b ${HEX_VERSION} --depth 1
 script:
   - mix test --include integration
   - sudo cat /var/log/postgresql/postgresql-9.6-main.log
   - mix run priv/repo/seeds.exs
-  - cd hex; mix deps.get && mix test --include integration
+  - cd hex; PATH=$(pwd)/../hex_elixir/bin:${PATH} ../hex_elixir/bin/mix deps.get; cd ..
+  - cd hex; PATH=$(pwd)/../hex_elixir/bin:${PATH} ../hex_elixir/bin/mix test --include integration; cd ..
 notifications:
   recipients:
   - eric.meadows.jonsson@gmail.com
-  slack:
-    secure: D21dsphy22i/G+yujf1V4f2x9pnbmTr2BkZv3nifXggTXY+ObItQ2MM/j9AoObdusbV63eSpvBZTIfX/oe7DQjN8hHBc/aILMZMLq7gKpOCTLtWIVvS9vNkyLa33EWwF/CsMiYQh377vye8a7cvORlkPmf+rNV//E9mbpuIWzBI=