BAEL-4742-Guide-To-System-Stubs

2020-11-20 17:44:42 +00:00
parent 683215b2fe
commit 390b864ff3
2 changed files with 90 additions and 0 deletions
@@ -0,0 +1,49 @@
+package com.baeldung.systemstubs;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import uk.org.webcompere.systemstubs.environment.EnvironmentVariables;
+import uk.org.webcompere.systemstubs.jupiter.SystemStub;
+import uk.org.webcompere.systemstubs.jupiter.SystemStubsExtension;
+import uk.org.webcompere.systemstubs.properties.SystemProperties;
+
+import static com.github.stefanbirkner.systemlambda.SystemLambda.restoreSystemProperties;
+import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
+import static org.junit.Assert.assertEquals;
+
+@ExtendWith(SystemStubsExtension.class)
+class SystemLambdaComparisonUnitTest {
+    @SystemStub
+    private EnvironmentVariables environmentVariables =
+      new EnvironmentVariables("ADDRESS", "https://www.baeldung.com");
+
+    @SystemStub
+    private SystemProperties systemProperties = new SystemProperties();
+
+    @Test
+    void aSingleSystemLambda() throws Exception {
+        restoreSystemProperties(() -> {
+            System.setProperty("log_dir", "test/resources");
+            assertEquals("test/resources", System.getProperty("log_dir"));
+        });
+    }
+
+    @Test
+    void multipleSystemLambdas() throws Exception {
+        restoreSystemProperties(() -> {
+            withEnvironmentVariable("URL", "https://www.baeldung.com")
+                .execute(() -> {
+                    System.setProperty("log_dir", "test/resources");
+                    assertEquals("test/resources", System.getProperty("log_dir"));
+                    assertEquals("https://www.baeldung.com", System.getenv("URL"));
+                });
+        });
+    }
+
+    @Test
+    void multipleSystemStubs() {
+        System.setProperty("log_dir", "test/resources");
+        assertEquals("test/resources", System.getProperty("log_dir"));
+        assertEquals("https://www.baeldung.com", System.getenv("ADDRESS"));
+    }
+}