Merge pull request #219 from if6was9/cross-fork-compare

#218 enable cross fork compare

src/main/java/org/kohsuke/github/GHRepository.java

@@ -690,7 +690,23 @@ public GHCompare getCompare(GHCommit id1, GHCommit id2) throws IOException {
  }
 
  public GHCompare getCompare(GHBranch id1, GHBranch id2) throws IOException {
- return getCompare(id1.getName(),id2.getName());
+
+ GHRepository owner1 = id1.getOwner();
+ GHRepository owner2 = id2.getOwner();
+
+ // If the owner of the branches is different, we have a cross-fork compare.
+ if (owner1!=null && owner2!=null) {
+ String ownerName1 = owner1.getOwnerName();
+ String ownerName2 = owner2.getOwnerName();
+ if (!StringUtils.equals(ownerName1, ownerName2)) {
+ String qualifiedName1 = String.format("%s:%s", ownerName1, id1.getName());
+ String qualifiedName2 = String.format("%s:%s", ownerName2, id2.getName());
+ return getCompare(qualifiedName1, qualifiedName2);
+ }
+ }
+
+ return getCompare(id1.getName(), id2.getName());
+
  }
 
  /**