Adding some 'bt' command line tests. Had to restructure how System.exit is called due to the Java agent throwing an execution for tracking.

settings.gradle

@@ -1,9 +1,11 @@
 include 'api'
 include 'tools:bt'
 include 'tools:st'
+include 'tools:tests'
 
 rootProject.name = 'bastools'
 project(":api").name = 'bastools-api'
 project(":tools").name = 'bastools-tools'
 project(":tools:bt").name = 'bastools-tools-bt'
 project(":tools:st").name = 'bastools-tools-st'
+project(":tools:tests").name = 'bastools-tools-tests'

tools/bt/src/main/java/io/github/applecommander/bastools/tools/bt/Main.java

@@ -49,7 +49,7 @@ import picocli.CommandLine.Parameters;
 		optionListHeading = "%nOptions:%n",
 		name = "bt", mixinStandardHelpOptions = true, 
 		versionProvider = VersionProvider.class)
-public class Main implements Callable<Void> {
+public class Main implements Callable<Integer> {
 	private static final int BAS = 0xfc;
 	
 	@Option(names = { "-o", "--output" }, description = "Write binary output to file.")
@@ -118,9 +118,11 @@ public class Main implements Callable<Void> {
 	private File sourceFile;
 	
 	public static void main(String[] args) {
+		// The CLI unit test library throws an exception when 'System.exit' is called;
+		// so we cannot have the 'System.exit' call in the try-catch block!
+		int exitCode = 0;
 		try {
-			int exitCode = new CommandLine(new Main()).execute(args);
-			System.exit(exitCode);
+			exitCode = new CommandLine(new Main()).execute(args);
 		} catch (Throwable t) {
 			if (Main.debugFlag) {
 				t.printStackTrace(System.err);
@@ -132,12 +134,13 @@ public class Main implements Callable<Void> {
 				}
 				System.err.printf("Error: %s\n", Optional.ofNullable(message).orElse("An error occurred."));
 			}
-			System.exit(1);
+			exitCode = 1;
 		}
+		System.exit(exitCode);
 	}
 	
 	@Override
-	public Void call() throws IOException {
+	public Integer call() throws IOException {
 		if (checkParameters()) {
 			Configuration.Builder builder = Configuration.builder()
 					.maxLineLength(this.maxLineLength)
@@ -147,7 +150,7 @@ public class Main implements Callable<Void> {
 			process(builder.build());
 		}
 		
-		return null;		// To satisfy object "Void"
+		return 0;
 	}
 	
 	/** A basic test to ensure parameters are somewhat sane. */

tools/tests/build.gradle

@@ -0,0 +1,24 @@
+plugins {
+    id 'java'
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation project(':bastools-tools:bastools-tools-bt')
+
+    testImplementation platform('org.junit:junit-bom:5.10.0')
+    testImplementation 'org.junit.jupiter:junit-jupiter'
+    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+    testImplementation "io.github.a2geek:clth:2.0"
+}
+
+test {
+    useJUnitPlatform()
+
+    def junit5SystemExit = configurations.testRuntimeClasspath.files
+            .find { it.name.contains('junit5-system-exit') }
+    jvmArgumentProviders.add({["-javaagent:$junit5SystemExit"]} as CommandLineArgumentProvider)
+}

tools/tests/src/test/java/io/github/applecommander/bastools/tools/tests/CommandLineTests.java

@@ -0,0 +1,39 @@
+package io.github.applecommander.bastools.tools.tests;
+
+import io.github.a2geek.clth.Config;
+import io.github.a2geek.clth.JUnitHelper;
+import io.github.a2geek.clth.TestHarness;
+import io.github.a2geek.clth.TestSuite;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UncheckedIOException;
+import java.util.stream.Stream;
+
+public class CommandLineTests {
+    @ParameterizedTest(name = "{1}: {2}")
+    @MethodSource("testCasesBT")
+    public void testBT(TestSuite testSuite, String name, String parameters) {
+        final TestHarness.Settings settings = TestHarness.settings()
+            .deleteFiles()
+            .enableAlwaysShowOutput()
+            .get();
+        TestHarness.run(testSuite, JUnitHelper::execute, settings);
+    }
+
+    public static Stream<Arguments> testCasesBT() {
+        try (InputStream inputStream = CommandLineTests.class.getResourceAsStream("/bt-config.yml")) {
+            assert inputStream != null;
+            String document = new String(inputStream.readAllBytes());
+            Config config = Config.load(document);
+
+            return TestSuite.build(config)
+                .map(t -> Arguments.of(t, t.testName(), String.join(" ", t.variables().values())));
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+}

tools/tests/src/test/resources/bt-config.yml

@@ -0,0 +1,65 @@
+commands:
+  bt:
+    main-class: io.github.applecommander.bastools.tools.bt.Main
+    system-exit: yes
+
+files:
+  helloWorld:
+    type: text
+    content: |
+      10 TEXT
+      20 HOME
+      30 PRINT "HELLO, WORLD"
+      40 END
+    suffix: .bas
+
+tests:
+  - name: Forms of help
+    steps:
+      - command: bt --help
+        criteria:
+          match: contains
+        stdout: "Usage: bt"
+      - command: bt
+        criteria:
+          match: contains
+        stderr: "Usage: bt"
+        rc: 2
+  - name: list output
+    steps:
+      - command: bt --list $helloWorld
+        criteria:
+          whitespace: trim
+        stdout: |
+          10  TEXT
+          20  HOME
+          30  PRINT "HELLO, WORLD"
+          40  END
+  - name: copy/paste output
+    steps:
+      - command: bt --copy $helloWorld
+        criteria:
+          whitespace: trim
+        stdout: |
+          0067:01 08 29 08 
+          0800:00
+          0801:07 08 0A 00 89 00 0D 08 14 00 97 00 21 08 1E 00
+          0811:BA 22 48 45 4C 4C 4F 2C 20 57 4F 52 4C 44 22 00
+          0821:27 08 28 00 80 00 00 00
+  - name: optimize output
+    steps:
+      - command: bt --optimize --list $helloWorld
+        criteria:
+          whitespace: trim
+        stdout: |
+          0  TEXT : HOME : PRINT "HELLO, WORLD": END
+  - name: wrap output
+    steps:
+      - command: bt --wrapper --hex $helloWorld
+        criteria:
+          whitespace: trim
+        stdout: |
+          0801: 16 08 0a 00 b9 31 30 33 2c 32 34 3a b9 31 30 34  .....103,24:.104
+          0811: 2c 38 3a ac 00 00 00 1e 08 0a 00 89 00 24 08 14  ,8:..........$..
+          0821: 00 97 00 38 08 1e 00 ba 22 48 45 4c 4c 4f 2c 20  ...8...."HELLO,
+          0831: 57 4f 52 4c 44 22 00 3e 08 28 00 80 00 00 00 ..  WORLD".>.(.....