Modify CI config to use stages and run linting.

.travis.yml

@@ -14,37 +14,50 @@ addons:
 cache:
   yarn: true
 
-env:
-  global:
-    # See https://git.io/vdao3 for details.
-    - JOBS=1
-  matrix:
-    # we recommend new addons test the current and previous LTS
-    # as well as latest stable release (bonus points to beta/canary)
-    - EMBER_TRY_SCENARIO=ember-1.13
-    - EMBER_TRY_SCENARIO=ember-lts-2.4
-    - EMBER_TRY_SCENARIO=ember-lts-2.8
-    - EMBER_TRY_SCENARIO=ember-lts-2.12
-    - EMBER_TRY_SCENARIO=ember-lts-2.16
-    - EMBER_TRY_SCENARIO=ember-lts-2.18
-    - EMBER_TRY_SCENARIO=ember-release
-    - EMBER_TRY_SCENARIO=ember-beta
-    - EMBER_TRY_SCENARIO=ember-canary
-    - EMBER_TRY_SCENARIO=module-unification
-
-matrix:
-  fast_finish: true
-  allow_failures:
-    - env: EMBER_TRY_SCENARIO=ember-canary
-
 before_install:
   - curl -o- -L https://yarnpkg.com/install.sh | bash
   - export PATH=$HOME/.yarn/bin:$PATH
 
 install:
-  - yarn install --no-lockfile --non-interactive
+  - yarn install
 
 script:
   # Usually, it's ok to finish the test scenario without reverting
   # to the addon's original dependency state, skipping "cleanup".
   - node_modules/.bin/ember try:one $EMBER_TRY_SCENARIO --skip-cleanup
+
+env:
+  global:
+    # See https://git.io/vdao3 for details.
+    - JOBS=1
+
+jobs:
+  fail_fast: true
+
+  include:
+    # runs tests in chrome with current locked deps and linting
+
+    - env: NAME=test # used only to make Travis UI show description
+      script:
+        - yarn lint:js
+        - yarn test
+
+    # If that passes:
+    # - run tests without pinned dependencies to catch issues with new versions
+    # - run tests in each supported ember version
+    - stage: additional tests
+      env: NAME=floating dependencies
+      install: yarn install --no-lockfile --non-interactive
+      script:
+        - yarn test
+
+    - env: EMBER_TRY_SCENARIO=ember-1.13
+    - env: EMBER_TRY_SCENARIO=ember-lts-2.4
+    - env: EMBER_TRY_SCENARIO=ember-lts-2.8
+    - env: EMBER_TRY_SCENARIO=ember-lts-2.12
+    - env: EMBER_TRY_SCENARIO=ember-lts-2.16
+    - env: EMBER_TRY_SCENARIO=ember-lts-2.18
+    - env: EMBER_TRY_SCENARIO=ember-release
+    - env: EMBER_TRY_SCENARIO=ember-beta
+    - env: EMBER_TRY_SCENARIO=ember-canary
+    - env: EMBER_TRY_SCENARIO=module-unification