add test

Author: jackie-coming

apollo-client/src/main/java/com/ctrip/framework/apollo/internals/RemoteConfigRepository.java

@@ -249,10 +249,21 @@ private ApolloConfig loadApolloConfig() {
           ApolloConfig result = response.getBody();
           if(result!=null){
             ConfigSyncType configSyncType=ConfigSyncType.fromString(result.getConfigSyncType());
+
             if(configSyncType!=null&&configSyncType.equals(ConfigSyncType.INCREMENTALSYNC)){
-              ApolloConfig apolloConfig = m_configCache.get()==null?new ApolloConfig():m_configCache.get();
-              result.setConfigurations(mergeConfigurations(apolloConfig.getConfigurations(),result.getConfigurationChanges()));
+
+              Map<String, String> previousConfigurations=null;
+
+              ApolloConfig previousConfig = m_configCache.get();
+
+              if(previousConfig!=null){
+                previousConfigurations=previousConfig.getConfigurations();
+              }
+
+              result.setConfigurations(mergeConfigurations(previousConfigurations,result.getConfigurationChanges()));
+
             }
+
           }
 
           logger.debug("Loaded config for {}: {}", m_namespace, result);
@@ -362,10 +373,11 @@ private List<ServiceDTO> getConfigServices() {
     return services;
   }
 
-  private Map<String, String> mergeConfigurations(Map<String, String> configurations,List<ConfigurationChange> configurationChanges) {
+  public Map<String, String> mergeConfigurations(Map<String, String> previousConfigurations,List<ConfigurationChange> configurationChanges) {
     Map<String, String> newConfigurations = new HashMap<>();
-    if(configurations!=null){
-      Maps.newHashMap(configurations);
+
+    if(previousConfigurations!=null){
+      newConfigurations=Maps.newHashMap(previousConfigurations);
     }
 
     if (configurationChanges == null) {

apollo-client/src/test/java/com/ctrip/framework/apollo/internals/RemoteConfigRepositoryTest.java

@@ -196,6 +196,73 @@ public void testLoadConfigWithIncrementalSync() throws Exception {
     remoteConfigLongPollService.stopLongPollingRefresh();
   }
 
+  @Test
+  public void testMergeConfigurations() throws Exception {
+    String key1 = "key1";
+    String value1 = "value1";
+    String anotherValue1 = "anotherValue1";
+
+    String key3 = "key3";
+    String value3 = "value3";
+    Map<String, String> previousConfigurations = ImmutableMap.of(key1, value1,key3,value3);
+
+    List<ConfigurationChange> configurationChanges=new ArrayList<>();
+    configurationChanges.add(new ConfigurationChange(key1, anotherValue1, ConfigurationChangeType.MODIFIED));
+    String key2 = "key2";
+    String value2 = "value2";
+    configurationChanges.add(new ConfigurationChange(key2, value2, ConfigurationChangeType.ADDED));
+    configurationChanges.add(new ConfigurationChange(key3, null, ConfigurationChangeType.DELETED));
+
+    RemoteConfigRepository remoteConfigRepository = new RemoteConfigRepository(someNamespace);
+    Map<String, String> result=remoteConfigRepository.mergeConfigurations(previousConfigurations, configurationChanges);
+
+    assertEquals(2, result.size());
+    assertEquals(anotherValue1, result.get(key1));
+    assertEquals(value2, result.get(key2));
+  }
+  @Test
+  public void testMergeConfigurationWithPreviousConfigurationsIsNULL() throws Exception {
+    String key1 = "key1";
+    String value1 = "value1";
+
+    String key3 = "key3";
+    String value3 = "value3";
+
+    Map<String, String> previousConfigurations = ImmutableMap.of(key1, value1,key3,value3);
+
+
+    RemoteConfigRepository remoteConfigRepository = new RemoteConfigRepository(someNamespace);
+    Map<String, String> result=remoteConfigRepository.mergeConfigurations(previousConfigurations, null);
+
+    assertEquals(2, result.size());
+    assertEquals(value1, result.get(key1));
+    assertEquals(value3, result.get(key3));
+  }
+
+  @Test
+  public void testMergeConfigurationWithChangesIsNULL() throws Exception {
+    String key1 = "key1";
+    String value1 = "value1";
+    String anotherValue1 = "anotherValue1";
+
+    String key3 = "key3";
+    String value3 = "value3";
+
+    List<ConfigurationChange> configurationChanges=new ArrayList<>();
+    configurationChanges.add(new ConfigurationChange(key1, anotherValue1, ConfigurationChangeType.MODIFIED));
+    String key2 = "key2";
+    String value2 = "value2";
+    configurationChanges.add(new ConfigurationChange(key2, value2, ConfigurationChangeType.ADDED));
+    configurationChanges.add(new ConfigurationChange(key3, null, ConfigurationChangeType.DELETED));
+
+    RemoteConfigRepository remoteConfigRepository = new RemoteConfigRepository(someNamespace);
+    Map<String, String> result=remoteConfigRepository.mergeConfigurations(null, configurationChanges);
+
+    assertEquals(2, result.size());
+    assertEquals(anotherValue1, result.get(key1));
+    assertEquals(value2, result.get(key2));
+  }
+
   @Test
   public void testLoadConfigWithOrderedProperties() throws Exception {
     String someKey = "someKey";