Rework shellConversionService

- Replace old ConversionService impl with something more aligned
  with current boot code with partially shameless copy as
  shell is most likely working outside of web or webflux env
  by creating FormattingConversionService and hooking convertes
  from DefaultConversionService.
- This should work on most cases and giving user a hook
  to define their own service.

Author: jvalkeal

spring-shell-autoconfigure/src/main/java/org/springframework/shell/boot/ParameterResolverAutoConfiguration.java

@@ -4,7 +4,6 @@
 import java.util.stream.Collectors;
 
 import org.springframework.beans.factory.ObjectProvider;
-import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.convert.ConversionService;
@@ -16,7 +15,7 @@
 public class ParameterResolverAutoConfiguration {
 
 	@Bean
-	public ParameterResolver standardParameterResolver(@Qualifier("spring-shell") ConversionService conversionService,
+	public ParameterResolver standardParameterResolver(ConversionService conversionService,
 			ObjectProvider<ValueProvider> valueProviders) {
 		Set<ValueProvider> collect = valueProviders.orderedStream().collect(Collectors.toSet());
 		return new StandardParameterResolver(conversionService, collect);

spring-shell-autoconfigure/src/main/java/org/springframework/shell/boot/SpringShellAutoConfiguration.java

@@ -16,19 +16,17 @@
 
 package org.springframework.shell.boot;
 
-import java.util.Collection;
 import java.util.Set;
 
-import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.convert.ApplicationConversionService;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.core.convert.ConversionService;
-import org.springframework.core.convert.converter.Converter;
-import org.springframework.core.convert.converter.ConverterFactory;
-import org.springframework.core.convert.converter.GenericConverter;
 import org.springframework.core.convert.support.DefaultConversionService;
+import org.springframework.format.support.FormattingConversionService;
 import org.springframework.shell.CommandRegistry;
 import org.springframework.shell.ResultHandler;
 import org.springframework.shell.ResultHandlerService;
@@ -44,23 +42,13 @@
 public class SpringShellAutoConfiguration {
 
 	@Bean
-	@Qualifier("spring-shell")
+	@ConditionalOnMissingBean(ConversionService.class)
 	public ConversionService shellConversionService(ApplicationContext applicationContext) {
-		Collection<Converter> converters = applicationContext.getBeansOfType(Converter.class).values();
-		Collection<GenericConverter> genericConverters = applicationContext.getBeansOfType(GenericConverter.class).values();
-		Collection<ConverterFactory> converterFactories = applicationContext.getBeansOfType(ConverterFactory.class).values();
-
-		DefaultConversionService defaultConversionService = new DefaultConversionService();
-		for (Converter converter : converters) {
-			defaultConversionService.addConverter(converter);
-		}
-		for (GenericConverter genericConverter : genericConverters) {
-			defaultConversionService.addConverter(genericConverter);
-		}
-		for (ConverterFactory converterFactory : converterFactories) {
-			defaultConversionService.addConverterFactory(converterFactory);
-		}
-		return defaultConversionService;
+		FormattingConversionService service = new FormattingConversionService();
+		DefaultConversionService.addDefaultConverters(service);
+		DefaultConversionService.addCollectionConverters(service);
+		ApplicationConversionService.addBeans(service, applicationContext);
+		return service;
 	}
 
 	@Bean

spring-shell-samples/src/main/java/org/springframework/shell/samples/standard/ConversionExample.java

@@ -41,6 +41,11 @@ class DomainObject {
 	public String getValue() {
 		return value;
 	}
+
+	@Override
+	public String toString() {
+		return "DomainObject [value=" + value + "]";
+	}
 }
 
 @Component