Add test coverage for Utils

apollo-core/src/test/java/com/ctrip/framework/foundation/internals/UtilsTest.java

@@ -0,0 +1,89 @@
+package com.ctrip.framework.foundation.internals;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * @author Josh Knopp(https://github.com/joshknopp)
+ */
+class UtilsTest {
+    @Nested
+    class IsBlank {
+        @Test
+        void trueGivenNull() {
+            assertTrue(Utils.isBlank(null));
+        }
+
+        @Test
+        void trueGivenEmpty() {
+            assertTrue(Utils.isBlank(""));
+        }
+
+        @Test
+        void trueGivenWhitespace() {
+            assertTrue(Utils.isBlank("   "));
+        }
+
+        @Test
+        void falseGivenLoremIpsum() {
+            String value = "Lorem Ipsum";
+            assertFalse(Utils.isBlank("Lorem Ipsum"));
+        }
+
+        @Test
+        void falseGivenWhitepsacePadded() {
+            assertFalse(Utils.isBlank("   Lorem Ipsum   "));
+        }
+    }
+
+    @Nested
+    class IsOsWindows {
+        private String actualOsName;
+
+        @BeforeEach
+        void setUp() {
+            actualOsName = System.getProperty("os.name");
+        }
+
+        @AfterEach
+        void tearDown() {
+            System.setProperty("os.name", actualOsName);
+        }
+
+        @Test
+        void trueGivenWindows10() {
+            System.setProperty("os.name", "Windows 10");
+            assertTrue(Utils.isOSWindows());
+        }
+
+        @Test
+        void falseGivenMacOsX() {
+            System.setProperty("os.name", "Mac OS X");
+            assertFalse(Utils.isOSWindows());
+        }
+
+        @Test
+        void falseGivenBlank() {
+            System.setProperty("os.name", "");
+            assertFalse(Utils.isOSWindows());
+        }
+
+        // Explicitly calling out case sensitivity; author @nobodyiam should confirm whether this is intentional
+        @Test
+        void falseGivenAllUppercaseWindows() {
+            System.setProperty("os.name", "WINDOWS 10");
+            assertFalse(Utils.isOSWindows());
+        }
+
+        @Test
+        void falseGivenAllLowercaseWindows() {
+            System.setProperty("os.name", "windows 10");
+            assertFalse(Utils.isOSWindows());
+        }
+    }
+}