WIP

Author: Malax

test/spec/detection_spec.rb

@@ -7,7 +7,14 @@
     Hatchet::Runner.new('non-clojure-app', allow_failure: true).tap do |app|
       app.deploy do
         expect(app).not_to be_deployed
-        expect(app.output).to include("Could not find a 'project.clj' file! Please ensure it exists and is checked into Git.")
+        expect(clean_output(app.output)).to eq(<<~OUTPUT)
+          remote: -----> App not compatible with buildpack: $BUILDPACK_URL
+          remote:        Could not find a 'project.clj' file! Please ensure it exists and is checked into Git.
+
+          remote:        More info: https://devcenter.heroku.com/articles/buildpacks#detection-failure
+
+          remote:  !     Push failed
+        OUTPUT
       end
     end
   end

test/spec/spec_helper.rb

@@ -49,7 +49,8 @@ def http_get(app, options = {})
 def find_output_start_index(lines)
   # Find the first "app detected" line. This skips the buildpack list at the beginning which will contain a GitHub URL
   # for the buildpack under test that will be different for each PR/branch under test.
-  lines.index { |line| line.match?(/-----> .* app detected/) }
+  # For detection failures, look for the "App not compatible" line instead.
+  lines.index { |line| line.match?(/-----> .* app detected|-----> App not compatible with buildpack/) }
 end
 
 def find_output_end_index(lines)
@@ -82,6 +83,8 @@ def clean_output(output)
     %r{/tmp/build_[0-9a-f]{8}} => '$BUILD_DIR',
     # Build id
     /build_[0-9a-f]{8}/ => '$BUILD_ID',
+    # Buildpack URL in detection failure message
+    %r{https://github\.com/heroku/heroku-buildpack-clojure#[\w\-/]+} => '$BUILDPACK_URL',
 
     ##################################################
     # Java