Improved CLI argument handling using picocli

build.gradle

@@ -40,8 +40,8 @@ subprojects {
         implementation platform("org.eclipse.xtext:xtext-dev-bom:${xtextVersion}")
         // https://mvnrepository.com/artifact/com.google.inject/guice
         implementation group: 'com.google.inject', name: 'guice', version: guiceVersion
-        // https://mvnrepository.com/artifact/commons-cli/commons-cli
-        implementation group: 'commons-cli', name: 'commons-cli', version: commonsCliVersion
+        // https://picocli.info/
+        implementation group: 'info.picocli', name: 'picocli', version: picocliVersion
     }
     dependencies {
         implementation group: 'org.jetbrains.kotlin', name: 'kotlin-stdlib', version: kotlinVersion

gradle.properties

@@ -3,7 +3,7 @@ group=org.lflang
 version=0.4.1-SNAPSHOT
 
 [versions]
-commonsCliVersion=1.4
+picocliVersion=4.7.0
 googleJavaFormatVersion=1.15.0
 guiceVersion=5.1.0
 jacocoVersion=0.8.7

org.lflang.tests/src/org/lflang/tests/cli/CliToolTestFixture.java

@@ -27,6 +27,7 @@
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
@@ -113,7 +114,7 @@ public void checkOk() {
         }
 
         public void checkFailed() {
-            assertEquals(1, exitCode);
+            assertTrue(exitCode > 0);
         }
 
         public void checkNoErrorOutput() {

org.lflang.tests/src/org/lflang/tests/cli/LfcCliTest.java

@@ -62,7 +62,7 @@ public void testHelpArg() {
             .verify(result -> {
                 result.checkOk();
                 result.checkNoErrorOutput();
-                result.checkStdOut(containsString("usage: lfc"));
+                result.checkStdOut(containsString("Usage: lfc"));
             });
     }
 
@@ -81,8 +81,7 @@ public void testVersion() {
     public void testWrongCliArg() {
         lfcTester.run("--notanargument", "File.lf")
             .verify(result -> {
-                result.checkStdErr(containsString("Unrecognized option: --notanargument"));
-                result.checkStdErr(containsString("fatal error"));
+                result.checkStdErr(containsString("Unknown option: '--notanargument'"));
                 result.checkFailed();
             });
     }

org.lflang.tests/src/org/lflang/tests/cli/LffCliTest.java

@@ -68,7 +68,7 @@ public void testHelpArg() {
         ExecutionResult result = lffTester.run("--help", "--version");
         result.checkOk();
         result.checkNoErrorOutput();
-        result.checkStdOut(containsString("usage: lff"));
+        result.checkStdOut(containsString("Usage: lff"));
     }
 
     @Test
@@ -83,8 +83,7 @@ public void testVersion() {
     @Test
     public void testWrongCliArg() {
         ExecutionResult result = lffTester.run("--notanargument", "File.lf");
-        result.checkStdErr(containsString("Unrecognized option: --notanargument"));
-        result.checkStdErr(containsString("fatal error"));
+        result.checkStdErr(containsString("Unknown option: '--notanargument'"));
         result.checkFailed();
     }
 

org.lflang/build.properties

@@ -16,6 +16,5 @@ additional.bundles = org.eclipse.xtext.xbase,\
                      org.eclipse.emf.mwe2.launch,\
                      org.eclipse.emf.mwe2.lib,\
                      org.objectweb.asm,\
-                     org.apache.commons.logging,\
                      org.apache.log4j,\
                      com.ibm.icu