Issue-271: WIP integration test

Signed-off-by: l-1sqared <30831153+l-1squared@users.noreply.github.com>

jgiven-core/src/test/java/com/tngtech/jgiven/impl/ConfigTest.java

@@ -93,7 +93,9 @@ private static Config createNewTestInstance() throws Exception {
 
     private void setSystemProperty(String key, String value) {
         String originalValue = System.getProperty(key);
-        systemPropertiesBackup.put(key, originalValue);
+        if (!systemPropertiesBackup.containsKey(key)) {
+            systemPropertiesBackup.put(key, originalValue);
+        }
         if (value == null) {
             System.clearProperty(key);
         } else {

jgiven-tests/src/test/java/com/tngtech/jgiven/report/json/ReportConfigurationTest.java

@@ -0,0 +1,110 @@
+package com.tngtech.jgiven.report.json;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.tngtech.jgiven.Stage;
+import com.tngtech.jgiven.annotation.AfterScenario;
+import com.tngtech.jgiven.annotation.BeforeScenario;
+import com.tngtech.jgiven.junit.SimpleScenarioTest;
+import com.tngtech.jgiven.tests.TestScenarioRepository;
+import com.tngtech.jgiven.tests.TestScenarios;
+import java.io.File;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+import org.junit.runner.JUnitCore;
+import org.junit.runner.Request;
+
+public class ReportConfigurationTest extends SimpleScenarioTest<ReportConfigurationTest.ReportConfigurationTestStage> {
+
+    @Rule
+    public TemporaryFolder temporaryFolder = new TemporaryFolder();
+
+    @Test
+    public void jgiven_report_is_disabled_by_a_system_property() throws IOException {
+        File reportFolder = temporaryFolder.newFolder();
+        given().a_set_system_property("jgiven.report.dir", getWindowsCompatiblePath(reportFolder))
+            .and().a_set_system_property("jgiven.report.enabled", "false")
+            .and().a_Test_scenario();
+
+        when().the_test_is_executed_with_junit();
+
+        then().the_report_is_not_written_to(reportFolder);
+    }
+
+    @Test
+    public void jgiven_report_directory_is_set_via_a_system_property() throws IOException {
+        File reportFolder = temporaryFolder.newFolder();
+        given().a_set_system_property("jgiven.report.dir", getWindowsCompatiblePath(reportFolder))
+            .and().a_set_system_property("jgiven.report.enabled", "true")
+            .and().a_Test_scenario();
+
+        when().the_test_is_executed_with_junit();
+
+        then().the_report_is_written_to(reportFolder);
+    }
+
+    private String getWindowsCompatiblePath(File file) {
+        return file.getAbsolutePath().replace("\\", "/");
+    }
+
+    static class ReportConfigurationTestStage extends Stage<ReportConfigurationTestStage> {
+
+        private TestScenarioRepository.TestScenario testScenario;
+
+        private final Map<String, String> systemPropertiesBackup = new HashMap<>();
+
+        @BeforeScenario
+        private void createConfigurationFile() {
+            a_set_system_property("jgiven.report.dir", null);
+        }
+
+        ReportConfigurationTestStage a_set_system_property(String key, String value) {
+            String originalValue = System.getProperty(key);
+            if (!systemPropertiesBackup.containsKey(key)) {
+                systemPropertiesBackup.put(key, originalValue);
+            }
+            if (value == null) {
+                System.clearProperty(key);
+            } else {
+                System.setProperty(key, value);
+            }
+            return self();
+        }
+
+        ReportConfigurationTestStage a_Test_scenario() {
+            testScenario = new TestScenarioRepository.TestScenario(TestScenarios.class, "test_with_tag_annotation");
+            return self();
+        }
+
+        ReportConfigurationTestStage the_test_is_executed_with_junit() {
+            assertThat(testScenario).as("No matching test scenario found").isNotNull();
+
+            JUnitCore junitCore = new JUnitCore();
+            junitCore.run(Request.method(testScenario.testClass, testScenario.testMethod));
+            return self();
+        }
+
+        ReportConfigurationTestStage the_report_is_not_written_to(File file) {
+            assertThat(file).isEmptyDirectory();
+            return self();
+        }
+
+        ReportConfigurationTestStage the_report_is_written_to(File file) {
+            assertThat(file).isNotEmptyDirectory();
+            return self();
+        }
+
+        @AfterScenario
+        private void clearSystemProperties() {
+            systemPropertiesBackup.entrySet()
+                .stream()
+                .peek(entry -> System.clearProperty(entry.getKey()))
+                .filter(entry -> entry.getValue() != null)
+                .forEach(entry -> System.setProperty(entry.getKey(), entry.getValue()));
+        }
+    }
+}