Configure Travis CI to run SwiftLint

.travis.yml

@@ -1,8 +1,14 @@
 language: objective-c
 osx_image: xcode7.3
 
+install:
+
+- ./install_swiftlint.sh
+
 script:
 
+- swiftlint
+
 - xcodebuild test -project ./All-Pairs\ Shortest\ Paths/APSP/APSP.xcodeproj -scheme APSPTests
 - xcodebuild test -project ./Array2D/Tests/Tests.xcodeproj -scheme Tests
 - xcodebuild test -project ./AVL\ Tree/Tests/Tests.xcodeproj -scheme Tests

install_swiftlint.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+
+# Installs the SwiftLint package.
+# Tries to get the precompiled .pkg file from Github, but if that
+# fails just recompiles from source.
+
+set -e
+
+SWIFTLINT_PKG_PATH="/tmp/SwiftLint.pkg"
+SWIFTLINT_PKG_URL="https://github.com/realm/SwiftLint/releases/download/0.10.0/SwiftLint.pkg"
+
+wget --output-document=$SWIFTLINT_PKG_PATH $SWIFTLINT_PKG_URL
+
+if [ -f $SWIFTLINT_PKG_PATH ]; then
+  echo "SwiftLint package exists! Installing it..."
+  sudo installer -pkg $SWIFTLINT_PKG_PATH -target /
+else
+  echo "SwiftLint package doesn't exist. Compiling from source..." &&
+  git clone https://github.com/realm/SwiftLint.git /tmp/SwiftLint &&
+  cd /tmp/SwiftLint &&
+  git submodule update --init --recursive &&
+  sudo make install
+fi