Add new config keys for Thymeleaf 3.0.10 features

This commit adds the following configuration properties:

* `spring.thymeleaf.render-hidden-markers-before-checkboxes`
* `spring.thymeleaf.servlet.produce-partial-output-while-processing`

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java

@@ -154,6 +154,8 @@ public class ThymeleafAutoConfiguration {
 		public SpringTemplateEngine templateEngine() {
 			SpringTemplateEngine engine = new SpringTemplateEngine();
 			engine.setEnableSpringELCompiler(this.properties.isEnableSpringElCompiler());
+			engine.setRenderHiddenMarkersBeforeCheckboxes(
+					this.properties.isRenderHiddenMarkersBeforeCheckboxes());
 			this.templateResolvers.forEach(engine::addTemplateResolver);
 			this.dialects.orderedStream().forEach(engine::addDialect);
 			return engine;
@@ -198,6 +200,8 @@ public class ThymeleafAutoConfiguration {
 				resolver.setContentType(
 						appendCharset(this.properties.getServlet().getContentType(),
 								resolver.getCharacterEncoding()));
+				resolver.setProducePartialOutputWhileProcessing(this.properties
+						.getServlet().isProducePartialOutputWhileProcessing());
 				resolver.setExcludedViewNames(this.properties.getExcludedViewNames());
 				resolver.setViewNames(this.properties.getViewNames());
 				// This resolver acts as a fallback resolver (e.g. like a
@@ -245,6 +249,8 @@ public class ThymeleafAutoConfiguration {
 		public SpringWebFluxTemplateEngine templateEngine() {
 			SpringWebFluxTemplateEngine engine = new SpringWebFluxTemplateEngine();
 			engine.setEnableSpringELCompiler(this.properties.isEnableSpringElCompiler());
+			engine.setRenderHiddenMarkersBeforeCheckboxes(
+					this.properties.isRenderHiddenMarkersBeforeCheckboxes());
 			this.templateResolvers.forEach(engine::addTemplateResolver);
 			this.dialects.orderedStream().forEach(engine::addDialect);
 			return engine;

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafProperties.java

@@ -101,6 +101,14 @@ public class ThymeleafProperties {
 	 */
 	private boolean enableSpringElCompiler;
 
+	/**
+	 * Whether hidden form inputs acting as markers for checkboxes (which are omitted from
+	 * form submission when unchecked) should be rendered before or after the rendered
+	 * checkbox element itself for better integration with some CSS frameworks. Default is
+	 * "false" (hiddens will be rendered after checkboxes).
+	 */
+	private boolean renderHiddenMarkersBeforeCheckboxes;
+
 	/**
 	 * Whether to enable Thymeleaf view resolution for Web frameworks.
 	 */
@@ -206,6 +214,15 @@ public class ThymeleafProperties {
 		this.enableSpringElCompiler = enableSpringElCompiler;
 	}
 
+	public boolean isRenderHiddenMarkersBeforeCheckboxes() {
+		return renderHiddenMarkersBeforeCheckboxes;
+	}
+
+	public void setRenderHiddenMarkersBeforeCheckboxes(
+			boolean renderHiddenMarkersBeforeCheckboxes) {
+		this.renderHiddenMarkersBeforeCheckboxes = renderHiddenMarkersBeforeCheckboxes;
+	}
+
 	public Reactive getReactive() {
 		return this.reactive;
 	}
@@ -221,6 +238,14 @@ public class ThymeleafProperties {
 		 */
 		private MimeType contentType = MimeType.valueOf("text/html");
 
+		/**
+		 * Whether Thymeleaf should start sending partial output to the server's output
+		 * buffers as soon as it becomes available (default), or instead wait until
+		 * template processing is finished, keeping all rendered results in memory until
+		 * that moment and sending them to the server's output buffers in a single call.
+		 */
+		private boolean producePartialOutputWhileProcessing = true;
+
 		public MimeType getContentType() {
 			return this.contentType;
 		}
@@ -229,6 +254,15 @@ public class ThymeleafProperties {
 			this.contentType = contentType;
 		}
 
+		public boolean isProducePartialOutputWhileProcessing() {
+			return producePartialOutputWhileProcessing;
+		}
+
+		public void setProducePartialOutputWhileProcessing(
+				boolean producePartialOutputWhileProcessing) {
+			this.producePartialOutputWhileProcessing = producePartialOutputWhileProcessing;
+		}
+
 	}
 
 	public static class Reactive {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafReactiveAutoConfigurationTests.java

@@ -162,6 +162,21 @@ public class ThymeleafReactiveAutoConfigurationTests {
 				.getEnableSpringELCompiler()).isFalse();
 	}
 
+	@Test
+	public void overrideRenderHiddenMarkersBeforeCheckboxes() {
+		load(BaseConfiguration.class,
+				"spring.thymeleaf.render-hidden-markers-before-checkboxes:true");
+		assertThat(this.context.getBean(SpringWebFluxTemplateEngine.class)
+				.getRenderHiddenMarkersBeforeCheckboxes()).isTrue();
+	}
+
+	@Test
+	public void enableRenderHiddenMarkersBeforeCheckboxesIsDisabledByDefault() {
+		load(BaseConfiguration.class);
+		assertThat(this.context.getBean(SpringWebFluxTemplateEngine.class)
+				.getRenderHiddenMarkersBeforeCheckboxes()).isFalse();
+	}
+
 	@Test
 	public void templateLocationDoesNotExist() {
 		load(BaseConfiguration.class,

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafServletAutoConfigurationTests.java

@@ -107,6 +107,21 @@ public class ThymeleafServletAutoConfigurationTests {
 		assertThat(views.getContentType()).isEqualTo("text/html;charset=UTF-16");
 	}
 
+	@Test
+	public void overrideDisableProducePartialOutputWhileProcessing() {
+		load(BaseConfiguration.class,
+				"spring.thymeleaf.servlet.produce-partial-output-while-processing:false");
+		assertThat(this.context.getBean(ThymeleafViewResolver.class)
+				.getProducePartialOutputWhileProcessing()).isFalse();
+	}
+
+	@Test
+	public void disableProducePartialOutputWhileProcessingIsEnabledByDefault() {
+		load(BaseConfiguration.class);
+		assertThat(this.context.getBean(ThymeleafViewResolver.class)
+				.getProducePartialOutputWhileProcessing()).isTrue();
+	}
+
 	@Test
 	public void overrideTemplateResolverOrder() {
 		load(BaseConfiguration.class, "spring.thymeleaf.templateResolverOrder:25");
@@ -135,6 +150,21 @@ public class ThymeleafServletAutoConfigurationTests {
 				.getEnableSpringELCompiler()).isFalse();
 	}
 
+	@Test
+	public void overrideRenderHiddenMarkersBeforeCheckboxes() {
+		load(BaseConfiguration.class,
+				"spring.thymeleaf.render-hidden-markers-before-checkboxes:true");
+		assertThat(this.context.getBean(SpringTemplateEngine.class)
+				.getRenderHiddenMarkersBeforeCheckboxes()).isTrue();
+	}
+
+	@Test
+	public void enableRenderHiddenMarkersBeforeCheckboxesIsDisabledByDefault() {
+		load(BaseConfiguration.class);
+		assertThat(this.context.getBean(SpringTemplateEngine.class)
+				.getRenderHiddenMarkersBeforeCheckboxes()).isFalse();
+	}
+
 	@Test
 	public void templateLocationDoesNotExist() {
 		load(BaseConfiguration.class,