Wrong arity for default boolean type

- Set boolean type arity zero or more as default.
- Backport #675
- Fixes #678

Author: jvalkeal

spring-shell-standard/src/main/java/org/springframework/shell/standard/StandardMethodTargetRegistrar.java

@@ -157,10 +157,10 @@ else if ("-".equals(shellMapping.prefix()) && stripped.length() == 1) {
 							}
 							else {
 								if (ClassUtils.isAssignable(boolean.class, parameterType)) {
-									optionSpec.arity(OptionArity.ZERO);
+									optionSpec.arity(OptionArity.ZERO_OR_ONE);
 								}
 								else if (ClassUtils.isAssignable(Boolean.class, parameterType)) {
-									optionSpec.arity(OptionArity.ZERO);
+									optionSpec.arity(OptionArity.ZERO_OR_ONE);
 								}
 								else {
 									optionSpec.arity(OptionArity.EXACTLY_ONE);
@@ -201,10 +201,10 @@ else if (ClassUtils.isAssignable(Boolean.class, parameterType)) {
 								.required()
 								.position(mp.getParameterIndex());
 							if (ClassUtils.isAssignable(boolean.class, parameterType)) {
-								optionSpec.arity(OptionArity.ZERO);
+								optionSpec.arity(OptionArity.ZERO_OR_ONE);
 							}
 							else if (ClassUtils.isAssignable(Boolean.class, parameterType)) {
-								optionSpec.arity(OptionArity.ZERO);
+								optionSpec.arity(OptionArity.ZERO_OR_ONE);
 							}
 							else {
 								optionSpec.arity(OptionArity.EXACTLY_ONE);

spring-shell-standard/src/test/java/org/springframework/shell/standard/StandardMethodTargetRegistrarTests.java

@@ -417,16 +417,29 @@ public void testOptionValuesWithBoolean() {
 		assertThat(catalog.getRegistrations().get("foo1").getOptions()).hasSize(1);
 		assertThat(catalog.getRegistrations().get("foo1").getOptions().get(0).getDefaultValue()).isEqualTo("false");
 		assertThat(catalog.getRegistrations().get("foo1").getOptions().get(0).isRequired()).isFalse();
+		assertThat(catalog.getRegistrations().get("foo1").getOptions().get(0).getArityMin()).isEqualTo(0);
+		assertThat(catalog.getRegistrations().get("foo1").getOptions().get(0).getArityMax()).isEqualTo(1);
 
 		assertThat(catalog.getRegistrations().get("foo2")).isNotNull();
 		assertThat(catalog.getRegistrations().get("foo2").getOptions()).hasSize(1);
 		assertThat(catalog.getRegistrations().get("foo2").getOptions().get(0).getDefaultValue()).isEqualTo("true");
 		assertThat(catalog.getRegistrations().get("foo2").getOptions().get(0).isRequired()).isFalse();
+		assertThat(catalog.getRegistrations().get("foo2").getOptions().get(0).getArityMin()).isEqualTo(0);
+		assertThat(catalog.getRegistrations().get("foo2").getOptions().get(0).getArityMax()).isEqualTo(1);
 
 		assertThat(catalog.getRegistrations().get("foo3")).isNotNull();
 		assertThat(catalog.getRegistrations().get("foo3").getOptions()).hasSize(1);
 		assertThat(catalog.getRegistrations().get("foo3").getOptions().get(0).isRequired()).isFalse();
 		assertThat(catalog.getRegistrations().get("foo3").getOptions().get(0).getDefaultValue()).isEqualTo("false");
+		assertThat(catalog.getRegistrations().get("foo3").getOptions().get(0).getArityMin()).isEqualTo(0);
+		assertThat(catalog.getRegistrations().get("foo3").getOptions().get(0).getArityMax()).isEqualTo(1);
+
+		assertThat(catalog.getRegistrations().get("foo4")).isNotNull();
+		assertThat(catalog.getRegistrations().get("foo4").getOptions()).hasSize(1);
+		assertThat(catalog.getRegistrations().get("foo4").getOptions().get(0).isRequired()).isTrue();
+		assertThat(catalog.getRegistrations().get("foo4").getOptions().get(0).getDefaultValue()).isNull();
+		assertThat(catalog.getRegistrations().get("foo4").getOptions().get(0).getArityMin()).isEqualTo(0);
+		assertThat(catalog.getRegistrations().get("foo4").getOptions().get(0).getArityMax()).isEqualTo(1);
 	}
 
 	@ShellComponent
@@ -443,6 +456,10 @@ public void foo2(@ShellOption(defaultValue = "true") boolean arg1) {
 		@ShellMethod(value = "foo3")
 		public void foo3(@ShellOption boolean arg1) {
 		}
+
+		@ShellMethod(value = "foo4")
+		public void foo4(boolean arg1) {
+		}
 	}
 
 	@Test