Add multiple Xcode versions to Travis build matrix

.travis.yml

@@ -1,5 +1,31 @@
-osx_image: xcode10.1
-language: swift
+
+matrix:
+  include:
+  - osx_image: xcode10
+    language: swift
+    env: TEST_DEVICE='platform=iOS Simulator,OS=12.0,name=iPhone SE'
+  - osx_image: xcode10.1
+    language: swift
+    env: TEST_DEVICE='platform=iOS Simulator,OS=12.1,name=iPhone SE'
+  - osx_image: xcode10.2
+    language: swift
+    env: TEST_DEVICE='platform=iOS Simulator,OS=12.2,name=iPhone SE'
+    after_success:
+    - bash <(curl -s https://codecov.io/bash)
+    before_deploy:
+    - brew outdated carthage || brew upgrade carthage
+    - carthage build --no-skip-current
+    - carthage archive $FRAMEWORK_NAME
+    deploy:
+      provider: releases
+      api_key:
+        secure: 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
+      file: "$FRAMEWORK_NAME.framework.zip"
+      skip_cleanup: true
+      on:
+        repo: MaxDesiatov/XMLCoder
+        tags: true
+
 env:
   global:
   - FRAMEWORK_NAME=XMLCoder
@@ -12,26 +38,21 @@ script:
 - swiftformat --lint --verbose .
 - swiftlint
 - pod lib lint --verbose
-- xcodebuild test -enableCodeCoverage YES -scheme XMLCoder
+- >
+  xcodebuild test -enableCodeCoverage YES -scheme XMLCoder
+  -sdk iphonesimulator -destination "$TEST_DEVICE" | xcpretty
+- xcodebuild test -enableCodeCoverage YES -scheme XMLCoder -sdk macosx | xcpretty
+
 # this runs the tests the second time, but it's the only way to make sure
 # that `Package.swift` is in a good state and `swift test` can only generate
 # coverage reports in Swift 5.0, see this issue for more details:
 # https://github.com/apple/swift-package-manager/pull/1787
 - swift test
+
 # this is commented because installing Jazzy on Travis doesn't work ¯\_(ツ)_/¯ 
 # - ./docs.sh
-before_deploy:
-- brew outdated carthage || brew upgrade carthage
-- carthage build --no-skip-current
-- carthage archive $FRAMEWORK_NAME
-after_success:
-- bash <(curl -s https://codecov.io/bash)
-deploy:
-  provider: releases
-  api_key:
-    secure: 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
-  file: "$FRAMEWORK_NAME.framework.zip"
-  skip_cleanup: true
-  on:
-    repo: MaxDesiatov/XMLCoder
-    tags: true
+
+# jobs:
+#   include:
+#   - stage: deploy
+#     osx_image: xcode10.1