be explicit in tests

lib/ember_cli/runner.rb

@@ -36,11 +36,11 @@ def run!(command)
 
     def redirect(stream, pipes:)
       pipes.each do |pipe|
-        Thread.new do
-          Thread.current.abort_on_exception = true
-
-          IO.copy_stream(stream, pipe)
-        end
+        # Thread.new do
+        #   Thread.current.abort_on_exception = true
+        #
+        IO.copy_stream(stream, pipe)
+        # end
       end
     end
   end

spec/lib/ember_cli/runner_spec.rb

@@ -4,37 +4,33 @@
   describe "#run!" do
     context "when the command fails" do
       it "writes output to `out` streams" do
-        output_streams = Array.new(2) { StringIO.new }
+        stdout = StringIO.new
+        logfile = StringIO.new
         runner = EmberCli::Runner.new(
           err: [],
-          out: output_streams,
+          out: [stdout, logfile],
         )
 
         expect { runner.run!(command_with_error(out: "out")) }.
           to raise_error(SystemExit)
 
-        ouput_strings = output_streams.each(&:rewind).map(&:read)
-
-        ouput_strings.each do |output|
-          expect(output.split).to eq(%w[out out])
-        end
+        expect(split_output_from_stream(stdout)).to eq(%w[out out])
+        expect(split_output_from_stream(logfile)).to eq(%w[out out])
       end
 
       it "writes errors to `err` streams" do
-        error_streams = Array.new(2) { StringIO.new }
+        stderr = StringIO.new
+        logfile = StringIO.new
         runner = EmberCli::Runner.new(
-          err: error_streams,
+          err: [stderr, logfile],
           out: [],
         )
 
         expect { runner.run!(command_with_error(err: "err")) }.
           to raise_error(SystemExit)
 
-        error_strings = error_streams.each(&:rewind).map(&:read)
-
-        error_strings.each do |error|
-          expect(error.split).to eq(%w[err err])
-        end
+        expect(split_output_from_stream(stderr)).to eq(%w[err err])
+        expect(split_output_from_stream(logfile)).to eq(%w[err err])
       end
     end
 
@@ -48,8 +44,14 @@
       [err, out].each(&:rewind)
 
       expect(status).to be_success
-      expect(err.read).to be_empty
-      expect(out.read).to eq("out\n")
+      expect(split_output_from_stream(err)).to be_empty
+      expect(split_output_from_stream(out)).to eq(%w[out])
+    end
+
+    def split_output_from_stream(stream)
+      stream.rewind
+
+      stream.read.split
     end
 
     def command(output)