Add base shell test system

- NOTE: very much wip and unstable
- This commit is a first step to provide boot style
  @ShellTest annotation
- New modules spring-shell-test and spring-shell-test-autoconfigure
- Focus is to autoconfigure context without shell runners so that
  we can create "sessions" and hook to configures jline terminal
  with custom in/out streams.
- Skeleton fork from jediterm to provide basic terminal emulation
  to part of a control amd escape characters working.
- ShellTestClient is a concept user can use to interact with a shell
  in a same way user would use a "real" shell.
- Fixes #489

spring-shell-samples/src/test/java/org/springframework/shell/samples/AbstractSampleTests.java

@@ -0,0 +1,60 @@
+/*
+ * 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.
+ * 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;
+
+import java.util.concurrent.TimeUnit;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Import;
+import org.springframework.shell.samples.standard.ResolvedCommands;
+import org.springframework.shell.test.ShellAssertions;
+import org.springframework.shell.test.ShellTestClient;
+import org.springframework.shell.test.ShellTestClient.BaseShellSession;
+import org.springframework.shell.test.ShellTestClient.InteractiveShellSession;
+import org.springframework.shell.test.ShellTestClient.NonInteractiveShellSession;
+import org.springframework.shell.test.autoconfigure.ShellTest;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.annotation.DirtiesContext.ClassMode;
+
+import static org.awaitility.Awaitility.await;
+
+@ShellTest
+@Import(ResolvedCommands.ResolvedCommandsConfiguration.class)
+@DirtiesContext(classMode = ClassMode.AFTER_EACH_TEST_METHOD)
+public class AbstractSampleTests {
+
+	@Autowired
+	protected ShellTestClient client;
+
+	protected void assertScreenContainsText(BaseShellSession<?> session, String text) {
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			ShellAssertions.assertThat(session.screen()).containsText(text);
+		});
+	}
+
+	protected BaseShellSession<?> createSession(String command, boolean interactive) {
+		if (interactive) {
+			InteractiveShellSession session = client.interactive().run();
+			session.write(session.writeSequence().command(command).build());
+			return session;
+		}
+		else {
+			String[] commands = command.split(" ");
+			NonInteractiveShellSession session = client.nonInterative(commands).run();
+			return session;
+		}
+	}
+}

spring-shell-samples/src/test/java/org/springframework/shell/samples/e2e/RequiredValueCommandsTests.java

@@ -0,0 +1,37 @@
+/*
+ * 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.
+ * 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.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import org.springframework.shell.samples.AbstractSampleTests;
+import org.springframework.shell.test.ShellTestClient.BaseShellSession;
+
+class RequiredValueCommandsTests extends AbstractSampleTests {
+
+	@ParameterizedTest
+	@CsvSource({
+		"e2e anno required-value,false",
+		"e2e reg required-value,false",
+		"e2e anno required-value,true",
+		"e2e reg required-value,true"
+	})
+	void shouldRequireOption(String command, boolean interactive) {
+		BaseShellSession<?> session = createSession(command, interactive);
+		assertScreenContainsText(session, "Missing mandatory option");
+	}
+}

spring-shell-samples/src/test/java/org/springframework/shell/samples/standard/ComponentCommandsTests.java

@@ -0,0 +1,85 @@
+/*
+ * 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.
+ * 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.standard;
+
+import java.util.concurrent.TimeUnit;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import org.springframework.shell.samples.AbstractSampleTests;
+import org.springframework.shell.test.ShellAssertions;
+import org.springframework.shell.test.ShellTestClient.BaseShellSession;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.awaitility.Awaitility.await;
+
+public class ComponentCommandsTests extends AbstractSampleTests {
+
+	@ParameterizedTest
+	@CsvSource({
+		"component single,false",
+		"component single,true"
+	})
+	void componentSingle(String command, boolean interactive) {
+		BaseShellSession<?> session = createSession(command, interactive);
+
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			assertThat(session.screen().lines()).anySatisfy(line -> {
+				assertThat(line).containsPattern("[>❯] key1");
+			});
+		});
+
+		session.write(session.writeSequence().keyDown().build());
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			assertThat(session.screen().lines()).anySatisfy(line -> {
+				assertThat(line).containsPattern("[>❯] key2");
+			});
+		});
+
+		session.write(session.writeSequence().cr().build());
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			ShellAssertions.assertThat(session.screen()).containsText("Got value value2");
+		});
+	}
+
+	@ParameterizedTest
+	@CsvSource({
+		"component multi,false",
+		"component multi,true"
+	})
+	void componentMulti(String command, boolean interactive) {
+		BaseShellSession<?> session = createSession(command, interactive);
+
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			assertThat(session.screen().lines()).anySatisfy(line -> {
+				assertThat(line).containsPattern("[>❯] (☐|\\[ \\])  key1");
+			});
+		});
+
+		session.write(session.writeSequence().space().build());
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			assertThat(session.screen().lines()).anySatisfy(line -> {
+				assertThat(line).containsPattern("[>❯] (☒|\\[x\\])  key1");
+			});
+		});
+
+		session.write(session.writeSequence().cr().build());
+		await().atMost(2, TimeUnit.SECONDS).untilAsserted(() -> {
+			ShellAssertions.assertThat(session.screen()).containsText("Got value value1,value2");
+		});
+	}
+}