Introduce ResponseEntity.internalServerError()

Closes gh-26952

Author: dreis2211

spring-web/src/main/java/org/springframework/http/ResponseEntity.java

@@ -317,6 +317,16 @@ public static BodyBuilder unprocessableEntity() {
 		return status(HttpStatus.UNPROCESSABLE_ENTITY);
 	}
 
+	/**
+	 * Create a builder with an
+	 * {@linkplain HttpStatus#INTERNAL_SERVER_ERROR INTERNAL_SERVER_ERROR} status.
+	 * @return the created builder
+	 * @since 5.3.8
+	 */
+	public static BodyBuilder internalServerError() {
+		return status(HttpStatus.INTERNAL_SERVER_ERROR);
+	}
+
 
 	/**
 	 * Defines a builder that adds headers to the response entity.

spring-web/src/test/java/org/springframework/http/ResponseEntityTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -159,6 +159,15 @@ public void unprocessableEntity() throws URISyntaxException {
 		assertThat(responseEntity.getBody()).isEqualTo("error");
 	}
 
+	@Test
+	public void internalServerError() throws URISyntaxException {
+		ResponseEntity<String> responseEntity = ResponseEntity.internalServerError().body("error");
+
+		assertThat(responseEntity).isNotNull();
+		assertThat(responseEntity.getStatusCode()).isEqualTo(HttpStatus.INTERNAL_SERVER_ERROR);
+		assertThat(responseEntity.getBody()).isEqualTo("error");
+	}
+
 	@Test
 	public void headers() throws URISyntaxException {
 		URI location = new URI("location");