Add test for the reporter

Test that the output generated by the reporter contains the
expected failed examples, flaky tests etc and in the right format.

test/test_helpers.rb

@@ -20,9 +20,16 @@ module TestHelpers
     w
   end
 
-  def exec_build(path, args = "")
+  # Executes an rspecq worker.
+  # @param [String] path The name of the test suite
+  # @param [String] args Extra rspeq arguments
+  # @param [String] :build_id By default build_id is generated by the method.
+  #   Alternatively you can pass the build_id in case you need to share it
+  #   with the reporter.
+  # @return [RSpecQ::Queue]
+  def exec_build(path, args = "", build_id: nil)
     worker_id = rand_id
-    build_id = rand_id
+    build_id ||= rand_id
 
     Dir.chdir(suite_path(path)) do
       out = `#{EXEC_CMD} --worker #{worker_id} --build #{build_id} #{args}`
@@ -37,6 +44,15 @@ module TestHelpers
     queue
   end
 
+  # Executes an rspecq reporter.
+  # @param [String] :build_id By default build_id is generated by the method.
+  # @return [String] The reporter's output.
+  def exec_reporter(build_id:)
+    out = `#{EXEC_CMD} --report --build #{build_id}`
+    puts out if ENV["RSPECQ_DEBUG"]
+    out
+  end
+
   def suite_path(path)
     File.join("test", "sample_suites", path)
   end

test/test_reporter.rb

@@ -0,0 +1,36 @@
+require "test_helpers"
+
+class TestReporter < RSpecQTest
+  def test_passing_suite
+    build_id = rand_id
+    exec_build("passing_suite", "", build_id: build_id)
+    output = exec_reporter(build_id: build_id)
+
+    assert_match "Total results", output
+    assert_match "1 examples (1 jobs)", output
+    assert_match "0 failures", output
+    assert_match "execution time", output
+    refute_match "Failed examples", output
+    refute_match "Flaky", output
+  end
+
+  def test_failing_suite
+    build_id = rand_id
+    exec_build("failing_suite", "", build_id: build_id)
+    output = exec_reporter(build_id: build_id)
+
+    assert_match "Failed examples", output
+    assert_match "bin/rspec ./spec/fail_1_spec.rb:3", output
+    refute_match "Flaky", output
+  end
+
+  def test_flakey_suite
+    build_id = rand_id
+    exec_build("flakey_suite", "", build_id: build_id)
+    output = exec_reporter(build_id: build_id)
+
+    assert_match "Flaky jobs detected", output
+    assert_match "./spec/foo_spec.rb[1:1]", output
+    refute_match "Failed examples", output
+  end
+end