Rework command subsystem

- Focus of these changes are to introduce a new command system based on
  real registrations (new way) instead of continuously (old way) resolve
  methods and its parameters via reflection.
- There's a lot of changes as this resolution via reflection had its
  hooks almost everywhere and thus most changes are just refactorings.
- Order to understand real changes I'd start to look classes under
  `org.springframework.shell.command` package as it defines new registration,
  catalog and parser classes. Also samples contain new classes to demonstrate
  new functionality.
- Fixes #380

spring-shell-standard-commands/src/test/java/org/springframework/shell/standard/commands/HelpTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 the original author or authors.
+ * Copyright 2022 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.
@@ -13,14 +13,12 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.springframework.shell.standard.commands;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.lang.reflect.Method;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
@@ -28,44 +26,45 @@ import java.util.Optional;
 
 import javax.validation.constraints.Max;
 
-import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.TestInfo;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mockito;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.core.convert.support.DefaultConversionService;
 import org.springframework.core.io.ClassPathResource;
-import org.springframework.shell.Command;
-import org.springframework.shell.CommandRegistry;
-import org.springframework.shell.MethodTarget;
-import org.springframework.shell.ParameterResolver;
+import org.springframework.shell.command.CommandCatalog;
+import org.springframework.shell.command.CommandRegistration;
 import org.springframework.shell.standard.ShellComponent;
 import org.springframework.shell.standard.ShellMethod;
 import org.springframework.shell.standard.ShellOption;
-import org.springframework.shell.standard.StandardParameterResolver;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit.jupiter.SpringExtension;
 import org.springframework.util.FileCopyUtils;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
-/**
- * Tests for the {@link Help} command.
- *
- * @author Eric Bottard
- */
 @ExtendWith(SpringExtension.class)
-@ContextConfiguration(classes = HelpTest.Config.class)
-public class HelpTest {
+@ContextConfiguration(classes = HelpTests.Config.class)
+public class HelpTests {
 
 	private static Locale previousLocale;
 	private String testName;
+	private Map<String, CommandRegistration> registrations = new HashMap<>();
+	private CommandsPojo commandsPojo = new CommandsPojo();
+
+	@MockBean
+	private CommandCatalog commandCatalog;
+
+	@Autowired
+	private Help help;
 
 	@BeforeAll
 	public static void setAssumedLocale() {
@@ -80,25 +79,106 @@ public class HelpTest {
 
 	@BeforeEach
 	public void setup(TestInfo testInfo) {
+		registrations.clear();
 		Optional<Method> testMethod = testInfo.getTestMethod();
 		if (testMethod.isPresent()) {
 			this.testName = testMethod.get().getName();
 		}
+		Mockito.when(commandCatalog.getRegistrations()).thenReturn(registrations);
 	}
 
-	@Autowired
-	private Help help;
-
 	@Test
 	public void testCommandHelp() throws Exception {
+		CommandRegistration registration = CommandRegistration.builder()
+			.command("first-command")
+			.help("A rather extensive description of some command.")
+			.withTarget()
+				.method(commandsPojo, "firstCommand")
+				.and()
+			.withOption()
+				.shortNames('r')
+				.description("Whether to delete recursively")
+				.type(boolean.class)
+				.and()
+			.withOption()
+				.shortNames('f')
+				.description("Do not ask for confirmation. YOLO")
+				.type(boolean.class)
+				.and()
+			.withOption()
+				.shortNames('n')
+				.description("The answer to everything")
+				.defaultValue("42")
+				.type(int.class)
+				.and()
+			.withOption()
+				.shortNames('o')
+				.description("Some other parameters")
+				.type(float[].class)
+				.and()
+			.build();
+		registrations.put("first-command", registration);
+		registrations.put("1st-command", registration);
 		CharSequence help = this.help.help("first-command").toString();
-		Assertions.assertThat(help).isEqualTo(sample());
+		assertThat(help).isEqualTo(sample());
 	}
 
 	@Test
 	public void testCommandList() throws Exception {
+		CommandRegistration registration1 = CommandRegistration.builder()
+			.command("first-command")
+			.help("A rather extensive description of some command.")
+			.withTarget()
+				.method(commandsPojo, "firstCommand")
+				.and()
+			.withOption()
+				.shortNames('r')
+				.and()
+			.build();
+		registrations.put("first-command", registration1);
+		registrations.put("1st-command", registration1);
+
+		CommandRegistration registration2 = CommandRegistration.builder()
+			.command("second-command")
+			.help("The second command. This one is known under several aliases as well.")
+			.withTarget()
+				.method(commandsPojo, "secondCommand")
+				.and()
+			.build();
+		registrations.put("second-command", registration2);
+		registrations.put("yet-another-command", registration2);
+
+		CommandRegistration registration3 = CommandRegistration.builder()
+			.command("second-command")
+			.help("The last command.")
+			.withTarget()
+				.method(commandsPojo, "thirdCommand")
+				.and()
+			.build();
+		registrations.put("third-command", registration3);
+
+		CommandRegistration registration4 = CommandRegistration.builder()
+			.command("first-group-command")
+			.help("The first command in a separate group.")
+			.group("Example Group")
+			.withTarget()
+				.method(commandsPojo, "firstCommandInGroup")
+				.and()
+			.build();
+		registrations.put("first-group-command", registration4);
+
+		CommandRegistration registration5 = CommandRegistration.builder()
+			.command("second-group-command")
+			.help("The second command in a separate group.")
+			.group("Example Group")
+			.withTarget()
+				.method(commandsPojo, "secondCommandInGroup")
+				.and()
+			.build();
+		registrations.put("second-group-command", registration5);
+
 		String list = this.help.help(null).toString();
-		Assertions.assertThat(list).isEqualTo(sample());
+		assertThat(list).isEqualTo(sample());
 	}
 
 	@Test
@@ -109,7 +189,7 @@ public class HelpTest {
 	}
 
 	private String sample() throws IOException {
-		InputStream is = new ClassPathResource(HelpTest.class.getSimpleName() + "-" + testName + ".txt", HelpTest.class).getInputStream();
+		InputStream is = new ClassPathResource(HelpTests.class.getSimpleName() + "-" + testName + ".txt", HelpTests.class).getInputStream();
 		return FileCopyUtils.copyToString(new InputStreamReader(is, "UTF-8")).replace("&", "");
 	}
 
@@ -117,62 +197,18 @@ public class HelpTest {
 	static class Config {
 
 		@Bean
-		public Help help(CommandRegistry commandRegistry) {
+		public Help help() {
 			return new Help();
 		}
 
-		@Bean
-		public CommandRegistry shell() {
-
-			return new CommandRegistry() {
-
-				@Override
-				public Map<String, MethodTarget> listCommands() {
-					Map<String, MethodTarget> result = new HashMap<>();
-					MethodTarget methodTarget = MethodTarget.of("firstCommand", commands(), new Command.Help("A rather extensive description of some command."));
-					result.put("first-command", methodTarget);
-					result.put("1st-command", methodTarget);
-
-					methodTarget = MethodTarget.of("secondCommand", commands(), new Command.Help("The second command. This one is known under several aliases as well."));
-					result.put("second-command", methodTarget);
-					result.put("yet-another-command", methodTarget);
-
-					methodTarget = MethodTarget.of("thirdCommand", commands(), new Command.Help("The last command."));
-					result.put("third-command", methodTarget);
-
-					methodTarget = MethodTarget.of("firstCommandInGroup", commands(), new Command.Help("The first command in a separate group.", "Example Group"));
-					result.put("first-group-command", methodTarget);
-
-					methodTarget = MethodTarget.of("secondCommandInGroup", commands(), new Command.Help("The second command in a separate group.", "Example Group"));
-					result.put("second-group-command", methodTarget);
-
-					return result;
-				}
-
-				@Override
-				public void addCommand(String name, MethodTarget target) {
-				}
-
-				@Override
-				public void removeCommand(String name) {
-				}
-			};
-		}
-
-		@Bean
-		public ParameterResolver parameterResolver() {
-			return new StandardParameterResolver(new DefaultConversionService(), Collections.emptySet());
-		}
-
-		@Bean
-		public Object commands() {
-			return new Commands();
-		}
-
+		// @Bean
+		// public ParameterResolver parameterResolver() {
+		// 	return new StandardParameterResolver(new DefaultConversionService(), Collections.emptySet());
+		// }
 	}
 
 	@ShellComponent
-	static class Commands {
+	static class CommandsPojo {
 
 		@ShellMethod(prefix = "--")
 		public void firstCommand(
@@ -186,28 +222,22 @@ public class HelpTest {
 		        // Single key, arity > 1.
 		        @ShellOption(help = "Some other parameters", arity = 3, value = "-o") float[] o
 		) {
-
 		}
 
 		@ShellMethod
 		public void secondCommand() {
-
 		}
 
 		@ShellMethod
 		public void thirdCommand() {
-
 		}
 
 		@ShellMethod
 		public void firstCommandInGroup() {
-
 		}
 
 		@ShellMethod
 		public void secondCommandInGroup() {
-
 		}
-
 	}
 }

spring-shell-standard-commands/src/test/resources/org/springframework/shell/standard/commands/HelpTests-testCommandHelp.txt

@@ -4,22 +4,22 @@ NAME
 	first-command - A rather extensive description of some command.
 
 SYNOPSYS
-	first-command [-r]  [-f]  [[-n] int]  [-o] float float float  
+	first-command [[-r] boolean]  [[-f] boolean]  [[-n] int]  [-o] float[]  
 
 OPTIONS
-	-r	Whether to delete recursively
+	-r  boolean
+		Whether to delete recursively
 		[Optional, default = false]
 
-	-f or --force
+	-f  boolean
 		Do not ask for confirmation. YOLO
 		[Optional, default = false]
 
 	-n  int
 		The answer to everything
 		[Optional, default = 42]
-		[must be less than or equal to 5]
 
-	-o  float float float
+	-o  float[]
 		Some other parameters
 		[Mandatory]