Merge pull request #6722 from rubygems/bump-pub-grub

Bump pub grub to latest

(cherry picked from commit 7988659)

bundler/lib/bundler/vendor/pub_grub/lib/pub_grub/version_solver.rb

@@ -162,7 +162,7 @@ def choose_package_version
     def resolve_conflict(incompatibility)
       logger.info { "conflict: #{incompatibility}" }
 
-      new_incompatibility = false
+      new_incompatibility = nil
 
       while !incompatibility.failure?
         most_recent_term = nil
@@ -204,7 +204,7 @@ def resolve_conflict(incompatibility)
           solution.backtrack(previous_level)
 
           if new_incompatibility
-            add_incompatibility(incompatibility)
+            add_incompatibility(new_incompatibility)
           end
 
           return incompatibility
@@ -219,9 +219,14 @@ def resolve_conflict(incompatibility)
           new_terms << difference.invert
         end
 
-        incompatibility = Incompatibility.new(new_terms, cause: Incompatibility::ConflictCause.new(incompatibility, most_recent_satisfier.cause))
+        new_incompatibility = Incompatibility.new(new_terms, cause: Incompatibility::ConflictCause.new(incompatibility, most_recent_satisfier.cause))
 
-        new_incompatibility = true
+        if incompatibility.to_s == new_incompatibility.to_s
+          logger.info { "!! failed to resolve conflicts, this shouldn't have happened" }
+          break
+        end
+
+        incompatibility = new_incompatibility
 
         partially = difference ? " partially" : ""
         logger.info { "! #{most_recent_term} is#{partially} satisfied by #{most_recent_satisfier.term}" }