Populate test security context with authentication

Add setAuthentication method on TestSecurityContextHolder.

test/src/main/java/org/springframework/security/test/context/TestSecurityContextHolder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2018 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@ package org.springframework.security.test.context;
 
 import javax.servlet.FilterChain;
 
+import org.springframework.security.core.Authentication;
 import org.springframework.security.core.context.SecurityContext;
 import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.security.test.web.servlet.request.SecurityMockMvcRequestPostProcessors;
@@ -51,6 +52,7 @@ import org.springframework.util.Assert;
  * </ul>
  *
  * @author Rob Winch
+ * @author Tadaya Tsuyukubo
  * @since 4.0
  *
  */
@@ -94,6 +96,21 @@ public final class TestSecurityContextHolder {
 		SecurityContextHolder.setContext(context);
 	}
 
+	/**
+	 * Creates a new {@link SecurityContext} with the given {@link Authentication}.
+	 * The {@link SecurityContext} is set on {@link TestSecurityContextHolder} and
+	 * {@link SecurityContextHolder}.
+	 *
+	 * @param authentication the {@link Authentication} to use
+	 * @since 5.1.1
+	 */
+	public static void setAuthentication(Authentication authentication) {
+		Assert.notNull(authentication, "Only non-null Authentication instances are permitted");
+		SecurityContext context = SecurityContextHolder.createEmptyContext();
+		context.setAuthentication(authentication);
+		setContext(context);
+	}
+
 	/**
 	 * Gets the default {@link SecurityContext} by delegating to the
 	 * {@link SecurityContextHolder}