Add dirty Git repo information to BuildInformation

Author: chrisseaton

src/processor/java/org/truffleruby/processor/BuildInformationProcessor.java

@@ -46,6 +46,7 @@ public class BuildInformationProcessor extends TruffleRubyProcessor {
     private String buildName;
     private String shortRevision;
     private String fullRevision;
+    private boolean isDirty;
     private String compileDate;
     private int copyrightYear;
     private String kernelMajorVersion;
@@ -58,6 +59,7 @@ public synchronized void init(ProcessingEnvironment env) {
             buildName = System.getenv("TRUFFLERUBY_BUILD_NAME");
             fullRevision = runCommand("git rev-parse HEAD");
             shortRevision = fullRevision.substring(0, 8);
+            isDirty = !runCommand("git status --porcelain").isBlank();
             compileDate = runCommand("git log -1 --date=short --pretty=format:%cd");
             copyrightYear = Integer.parseInt(compileDate.split("\\-")[0]);
             kernelMajorVersion = findKernelMajorVersion();

src/shared/java/org/truffleruby/shared/BuildInformation.java

@@ -20,6 +20,8 @@ public interface BuildInformation {
 
     String getFullRevision();
 
+    boolean isDirty();
+
     int getCopyrightYear();
 
     String getCompileDate();