(SDK-313) refactor cli/tests/unit_spec.rb

* extract common pre-conditions
* change SystemExit to detect missing exceptions
* move explicit $stdout expectations to output matchers

spec/unit/cli/test/unit_spec.rb

@@ -1,96 +1,87 @@
 require 'spec_helper'
 require 'pdk/tests/unit'
 
-describe 'Running `pdk test unit`' do
+describe '`pdk test unit`' do
   subject(:test_unit_cmd) { PDK::CLI.instance_variable_get(:@test_unit_cmd) }
 
   it { is_expected.not_to be_nil }
 
   context 'with --help' do
     it do
-      begin
-        expect {
-          PDK::CLI.run(['test', 'unit', '--help'])
-        }.to output(%r{^USAGE\s+pdk test unit}m).to_stdout
-      rescue SystemExit => e
+      expect {
+        PDK::CLI.run(['test', 'unit', '--help'])
+      }.to raise_error(SystemExit) { |e|
         expect(e.status).to eq 0
-      end
+      }.and output(%r{^USAGE\s+pdk test unit}m).to_stdout
     end
   end
 
-  context 'when listing tests' do
-    let(:args) { ['--list'] }
-
+  context 'when executing' do
     before(:each) do
       expect(PDK::CLI::Util).to receive(:ensure_in_module!).with(no_args).once
     end
 
-    context 'when no tests are found' do
-      before(:each) do
-        expect(PDK::Test::Unit).to receive(:list).with(no_args).once.and_return([])
-        expect($stdout).to receive(:puts).with(%r{No examples found})
-      end
-
-      it { test_unit_cmd.run_this(args) }
-    end
+    context 'when listing tests' do
+      let(:args) { ['--list'] }
 
-    context 'when some tests are found' do
-      let(:test_list) { [{ id: 'first_id', full_description: 'first_description' }, { id: 'second_id', full_description: 'second_description' }] }
+      context 'when no tests are found' do
+        before(:each) do
+          expect(PDK::Test::Unit).to receive(:list).with(no_args).once.and_return([])
+        end
 
-      before(:each) do
-        expect(PDK::Test::Unit).to receive(:list).with(no_args).once.and_return(test_list)
-        expect($stdout).to receive(:puts).with('Examples:')
-        expect($stdout).to receive(:puts).with(%r{first_id\tfirst_description})
-        expect($stdout).to receive(:puts).with(%r{second_id\tsecond_description})
+        it { expect { test_unit_cmd.run_this(args) }.to output(%r{No examples found}m).to_stdout }
       end
 
-      it { test_unit_cmd.run_this(args) }
-    end
-  end
-
-  context 'when running tests' do
-    context 'when tests pass' do
-      before(:each) do
-        expect(PDK::CLI::Util).to receive(:ensure_in_module!).with(no_args).once
-        expect(PDK::Test::Unit).to receive(:invoke).with(instance_of(PDK::Report), hash_including(:tests)).once.and_return(0)
-      end
+      context 'when some tests are found' do
+        let(:test_list) { [{ id: 'first_id', full_description: 'first_description' }, { id: 'second_id', full_description: 'second_description' }] }
 
-      it 'returns 0' do
-        begin
-          test_unit_cmd.run_this([])
-        rescue SystemExit => e
-          expect(e.status).to eq 0
+        before(:each) do
+          expect(PDK::Test::Unit).to receive(:list).with(no_args).once.and_return(test_list)
         end
+
+        it { expect { test_unit_cmd.run_this(args) }.to output(%r{Examples:\nfirst_id\tfirst_description\nsecond_id\tsecond_description}m).to_stdout }
       end
     end
 
-    context 'when tests pass, with a format option' do
-      before(:each) do
-        expect(PDK::CLI::Util).to receive(:ensure_in_module!).with(no_args).once
-        expect(PDK::CLI::Util::OptionNormalizer).to receive(:report_formats).with(['text:results.txt']).and_return([{ method: :write_text, target: 'results.txt' }]).twice
-        expect(PDK::Test::Unit).to receive(:invoke).with(instance_of(PDK::Report), hash_including(:tests)).once.and_return(0)
-      end
+    context 'when running tests' do
+      context 'when tests pass' do
+        before(:each) do
+          expect(PDK::Test::Unit).to receive(:invoke).with(instance_of(PDK::Report), hash_including(:tests)).once.and_return(0)
+        end
 
-      it 'returns 0' do
-        begin
-          test_unit_cmd.run_this(['--format=text:results.txt'])
-        rescue SystemExit => e
-          expect(e.status).to eq 0
+        it do
+          expect {
+            test_unit_cmd.run_this([])
+          }.to raise_error(SystemExit) { |e|
+            expect(e.status).to eq 0
+          }
         end
-      end
-    end
 
-    context 'when tests fail' do
-      before(:each) do
-        expect(PDK::CLI::Util).to receive(:ensure_in_module!).with(no_args).once
-        expect(PDK::Test::Unit).to receive(:invoke).with(instance_of(PDK::Report), hash_including(:tests)).once.and_return(1)
+        context 'with a format option' do
+          before(:each) do
+            expect(PDK::CLI::Util::OptionNormalizer).to receive(:report_formats).with(['text:results.txt']).and_return([{ method: :write_text, target: 'results.txt' }]).twice
+          end
+          it do
+            expect {
+              test_unit_cmd.run_this(['--format=text:results.txt'])
+            }.to raise_error(SystemExit) { |e|
+              expect(e.status).to eq 0
+            }
+          end
+        end
       end
 
-      it 'does not return 0' do
-        begin
-          test_unit_cmd.run_this([])
-        rescue SystemExit => e
-          expect(e.status).not_to eq 0
+      context 'when tests fail' do
+        before(:each) do
+          expect(PDK::Test::Unit).to receive(:invoke).with(instance_of(PDK::Report), hash_including(:tests)).once.and_return(1)
+        end
+
+        it do
+          expect {
+            test_unit_cmd.run_this([])
+          }.to raise_error(SystemExit) { |e|
+            expect(e.status).not_to eq 0
+          }
         end
       end
     end