Added stderr message when bin/detect fails

bin/detect

@@ -21,5 +21,6 @@ if detect_sbt $BUILD_DIR ; then
   fi
   exit 0
 else
-  echo "no" && exit 1
+  (>&2 echo "Could not find a 'build.sbt' file! Please ensure it exists and is checked into Git.")
+  exit 1
 fi

etc/hatchet.sh

@@ -2,14 +2,14 @@
 
 BUILDPACK_NAME="heroku-buildpack-scala"
 
-if [ "$CIRCLECI" == "true" && -n "$CI_PULL_REQUEST" ]; then
+if [ "$CIRCLECI" == "true" ] && [ -n "$CI_PULL_REQUEST" ]; then
   if [ "$CIRCLE_PR_USERNAME" != "heroku" ]; then
     echo "Skipping integration tests on forked PR."
     exit 0
   fi
 fi
 
-if [ "$TRAVIS" == "true" && "$TRAVIS_PULL_REQUEST" != "false" ]; then
+if [ "$TRAVIS" == "true" ] && [ "$TRAVIS_PULL_REQUEST" != "false" ]; then
   if [ "$TRAVIS_PULL_REQUEST_SLUG" != "heroku/$BUILDPACK_NAME" ]; then
     echo "Skipping integration tests on forked PR."
     exit 0

test/detect_test.sh

@@ -6,7 +6,7 @@ testDetect_SbtFileFoundInRoot()
 {
   touch ${BUILD_DIR}/something.sbt
 
-  detect  
+  detect
 
   assertAppDetected "Scala"
 }
@@ -79,7 +79,7 @@ testDetect_ApplicationConfFileDetectsAsPlay20Scala()
   touch ${BUILD_DIR}/app/something.scala
   mkdir ${BUILD_DIR}/app/views
   touch ${BUILD_DIR}/app/something.scala.html
-  
+
   detect
 
   assertAppDetected "Play 2.x - Scala"
@@ -95,7 +95,7 @@ testDetect_ApplicationConfFileDetectsAsPlay20Java()
   touch ${BUILD_DIR}/app/something.java
   mkdir ${BUILD_DIR}/app/views
   touch ${BUILD_DIR}/app/something.scala.html
-  
+
   detect
 
   assertAppDetected "Play 2.x - Java"
@@ -104,7 +104,7 @@ testDetect_ApplicationConfFileDetectsAsPlay20Java()
 
 testDetect_NotFound()
 {
-  detect  
-  
-  assertNoAppDetected
+  detect
+
+  assertEquals "1" "${RETURN}"
 }