Make PIP comment parsing in JBangIntegration more robust

Author: steve-s

.pre-commit-config.yaml

@@ -3,6 +3,7 @@ repos:
     rev: v5.0.0
     hooks:
     -   id: trailing-whitespace
+        exclude: ^integration-tests/jbang/EmptyPIPComments\.j$
     -   id: end-of-file-fixer
     -   id: check-yaml
     -   id: check-added-large-files

integration-tests/jbang/EmptyPIPComments.j

@@ -3,9 +3,9 @@
 //DEPS org.graalvm.python:jbang:${env.GRAALPY_VERSION:26.0.0}
 //PIP
 // one blank after PIP
-//PIP
+//PIP 
 // three blanks after PIP
-//PIP
+//PIP   
 
 public class EmptyPIPComments {
     public static void main(String[] args) {

org.graalvm.python.jbang/src/main/java/org/graalvm/python/jbang/JBangIntegration.java

@@ -180,8 +180,13 @@ public static Map<String, Object> postBuild(Path temporaryJar, Path pomFile,
 					resourcesDirectory = Path.of(path);
 				}
 			} else if (comment.startsWith(PIP)) {
-				pkgs.addAll(Arrays.stream(comment.substring(PIP.length()).trim().split(" "))
-						.filter(s -> !s.trim().isEmpty()).collect(Collectors.toList()));
+				String content = comment.substring(PIP.length()).trim();
+				if (!content.isEmpty()) {
+					// Some versions of JBang seem to pass "[null]" in the comment string for some
+					// reason, we filter that out
+					pkgs.addAll(Arrays.stream(content.split("\\s+")).filter(s -> !s.equals("[null]"))
+							.collect(Collectors.toList()));
+				}
 			}
 		}
 		if (!pkgs.isEmpty()) {