Added version arg to CLI (#1)

* Added version arg to CL

Added `--version` to the CL so that it shows the verifiers' current versison. Path specificity is needed due to it picking up the main pom file in the root instead of inside liquidjava-verifier.

* Updated version text

Co-authored-by: Ricardo Costa <rcosta.ms358@gmail.com>

---------

Co-authored-by: Ricardo Costa <rcosta.ms358@gmail.com>

Author: cheestree

liquidjava-verifier/src/main/java/liquidjava/api/CommandLineArgs.java

@@ -1,7 +1,11 @@
 package liquidjava.api;
 
+import java.io.FileReader;
+import java.nio.file.Path;
 import java.util.List;
-import java.util.concurrent.Callable;
+
+import org.apache.maven.model.Model;
+import org.apache.maven.model.io.xpp3.MavenXpp3Reader;
 
 import picocli.CommandLine.Command;
 import picocli.CommandLine.Option;
@@ -12,9 +16,22 @@ public class CommandLineArgs {
     @Option(names = {"-h", "--help"}, usageHelp = true, description = "Display this help message")
     public boolean help;
 
+    @Option(names = { "-v", "--version" }, versionHelp = true, description = "Display the version of LiquidJava")
+    public boolean version;
+
     @Option(names = { "-d", "--debug" }, description = "Enable debug mode for more detailed output")
     public boolean debugMode;
 
     @Parameters(arity = "1..*", paramLabel = "<...paths>", description = "Paths to be verified by LiquidJava")
     public List<String> paths;
+
+    public String getVersionString() {
+        Path pomPath = Path.of("liquidjava-verifier", "pom.xml");
+        try (FileReader fileReader = new FileReader(pomPath.toFile())) {
+            Model model = new MavenXpp3Reader().read(fileReader);
+            return model.getVersion();
+        } catch (Exception ignored) {
+            return "unknown";
+        }
+    }
 }

liquidjava-verifier/src/main/java/liquidjava/api/CommandLineLauncher.java

@@ -31,6 +31,11 @@ public static void main(String[] args) {
             return;
         }
 
+        if (cmd.isVersionHelpRequested()) {
+            System.out.println("liquidjava " + cmdArgs.getVersionString());
+            return;
+        }
+
         launch(cmdArgs.paths.stream().toArray(String[]::new));
 
         // print diagnostics