Support modify option names

- New OptionNameModifier which is just a Function<String,String> to
  modify a name.
- Can be defined per option in CommandRegistration.
- Can be defined as global default as bean.
- Default implementation for common case types is enabled via boot's
  config props under spring.shell.option.naming.case-type
- Support facilities for camel, kebab, snake and pascal conversions.
- Fixes #621

spring-shell-samples/src/main/java/org/springframework/shell/samples/e2e/OptionNamingCommands.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2023 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.shell.samples.e2e;
+
+import org.springframework.context.annotation.Bean;
+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.stereotype.Component;
+
+public class OptionNamingCommands {
+
+	@ShellComponent
+	public static class OptionNamingCommandsLegacyAnnotation extends BaseE2ECommands {
+
+		@ShellMethod(key = LEGACY_ANNO + "option-naming-1", group = GROUP)
+		public void testOptionNaming1Annotation(
+			@ShellOption("from_snake") String snake,
+			@ShellOption("fromCamel") String camel,
+			@ShellOption("from-kebab") String kebab,
+			@ShellOption("FromPascal") String pascal
+		) {
+		}
+
+	}
+
+	@Component
+	public static class OptionNamingCommandsRegistration extends BaseE2ECommands {
+
+		@Bean
+		public CommandRegistration testOptionNaming1Registration(CommandRegistration.BuilderSupplier builder) {
+			return builder.get()
+				.command(REG, "option-naming-1")
+				.group(GROUP)
+				.withOption()
+					.longNames("from_snake")
+					.required()
+					.and()
+				.withOption()
+					.longNames("fromCamel")
+					.required()
+					.and()
+				.withOption()
+					.longNames("from-kebab")
+					.required()
+					.and()
+				.withOption()
+					.longNames("FromPascal")
+					.required()
+					.and()
+				.withOption()
+					.longNames("arg1")
+					.nameModifier(name -> "x" + name)
+					.required()
+					.and()
+				.withTarget()
+					.consumer(ctx -> {})
+					.and()
+				.build();
+		}
+	}
+}

spring-shell-samples/src/main/resources/application.yml

@@ -2,6 +2,14 @@ spring:
   main:
     banner-mode: off
   shell:
+    ## pick global default option naming
+    # option:
+    #   naming:
+    #     case-type: noop
+    #     case-type: camel
+    #     case-type: snake
+    #     case-type: kebab
+    #     case-type: pascal
     config:
       env: SPRING_SHELL_SAMPLES_USER_HOME
       location: "{userconfig}/spring-shell-samples"