Ignore merge point candidates that create crosses

In OBS you can create submit requests for revisions that are behind
the last merge point, in git you can't - so we ignore them.

Fixes #14

lib/db_revision.py

@@ -31,6 +31,7 @@ class DBRevision:
         self.rev = float(self.rev)
         self._files = None
         self.db = db
+        self.git_commit = None
 
     def short_string(self):
         return f"{self.project}/{self.package}/{self.rev}"

lib/git_exporter.py

@@ -107,10 +107,12 @@ class GitExporter:
         if flat.parent1:
             if not self.branch_fits_parent1(flat, branch_state):
                 logging.info(f"Reset {flat.branch} onto {flat.parent1.short_string()}")
+                assert flat.parent1.git_commit
                 self.git.set_branch_head(flat.branch, flat.parent1.git_commit)
                 self.git.checkout(flat.branch)
             parents.append(flat.parent1.git_commit)
             if flat.parent2:
+                assert flat.parent2.git_commit
                 parents.append(flat.parent2.git_commit)
 
         # Overwrite ".gitattributes" with the

lib/tree_builder.py

@@ -104,14 +104,23 @@ class TreeBuilder:
         """For a given revision in the target, find the node in the source chain
         that matches the files"""
         node = source_chain
+        candidates = []
         while node:
             # exclude reverts happening after the merge
             if (
                 node.revision.commit_time <= revision.commit_time
                 and node.revision.files_hash == revision.files_hash
             ):
-                return node
+                candidates.append(node)
+            if node.merged_into:
+                # we can't have candidates that are crossing previous merges
+                # see https://gitea.opensuse.org/importers/git-importer/issues/14
+                candidates = []
             node = node.parent
+        if candidates:
+            # the assert is here to see if we have more hot cases
+            assert len(candidates) == 1
+            return candidates[0]
 
     def add_merge_points(self, factory_revisions):
         """For all target revisions that accepted a request, look up the merge

tests/fixtures/firewalld-expected-list.yaml

@@ -44,8 +44,7 @@
 - factory c:openSUSE:Factory/firewalld/53.0 p1:openSUSE:Factory/firewalld/52.0 p2:security:netfilter/firewalld/107.0
 - devel c:security:netfilter/firewalld/107.0 p1:security:netfilter/firewalld/106.0
 - factory c:openSUSE:Factory/firewalld/52.0 p1:openSUSE:Factory/firewalld/51.0
-- factory c:openSUSE:Factory/firewalld/51.0 p1:openSUSE:Factory/firewalld/50.0 p2:security:netfilter/firewalld/107.0
+- factory c:openSUSE:Factory/firewalld/51.0 p1:openSUSE:Factory/firewalld/50.0
-- devel c:security:netfilter/firewalld/107.0 p1:security:netfilter/firewalld/106.0
 - factory c:openSUSE:Factory/firewalld/50.0 p1:openSUSE:Factory/firewalld/49.0 p2:security:netfilter/firewalld/106.0
 - devel c:security:netfilter/firewalld/106.0 p1:security:netfilter/firewalld/105.0
 - factory c:openSUSE:Factory/firewalld/49.0 p1:openSUSE:Factory/firewalld/48.0 p2:security:netfilter/firewalld/105.0
@@ -89,13 +88,13 @@
 - devel c:security:netfilter/firewalld/82.0 p1:security:netfilter/firewalld/81.0
 - devel c:security:netfilter/firewalld/81.0 p1:security:netfilter/firewalld/80.0
 - devel c:security:netfilter/firewalld/80.0 p1:security:netfilter/firewalld/79.0
+- devel c:security:netfilter/firewalld/79.0 p1:security:netfilter/firewalld/78.0
+- devel c:security:netfilter/firewalld/78.0 p1:security:netfilter/firewalld/77.0
 - factory c:openSUSE:Factory/firewalld/34.0 p1:openSUSE:Factory/firewalld/33.0 p2:security:netfilter/firewalld/77.0
 - devel c:security:netfilter/firewalld/77.0 p1:security:netfilter/firewalld/76.0
 - devel c:security:netfilter/firewalld/76.0 p1:security:netfilter/firewalld/75.0
 - devel c:security:netfilter/firewalld/75.0 p1:security:netfilter/firewalld/74.0
-- factory c:openSUSE:Factory/firewalld/33.0 p1:openSUSE:Factory/firewalld/32.0 p2:security:netfilter/firewalld/79.0
+- factory c:openSUSE:Factory/firewalld/33.0 p1:openSUSE:Factory/firewalld/32.0
-- devel c:security:netfilter/firewalld/79.0 p1:security:netfilter/firewalld/78.0
-- devel c:security:netfilter/firewalld/78.0 p1:security:netfilter/firewalld/77.0
 - factory c:openSUSE:Factory/firewalld/32.0 p1:openSUSE:Factory/firewalld/31.0 p2:security:netfilter/firewalld/74.0
 - devel c:security:netfilter/firewalld/74.0 p1:security:netfilter/firewalld/71.0
 - factory c:openSUSE:Factory/firewalld/31.0 p1:openSUSE:Factory/firewalld/30.0

tests/fixtures/firewalld-expected-tree.yaml

@@ -65,8 +65,6 @@
   - security:netfilter/firewalld/107.0
 - commit: openSUSE:Factory/firewalld/52.0
 - commit: openSUSE:Factory/firewalld/51.0
-  merged:
-  - security:netfilter/firewalld/107.0
 - commit: openSUSE:Factory/firewalld/50.0
   merged:
   - security:netfilter/firewalld/106.0
@@ -126,15 +124,14 @@
   - security:netfilter/firewalld/82.0
   - security:netfilter/firewalld/81.0
   - security:netfilter/firewalld/80.0
+  - security:netfilter/firewalld/79.0
+  - security:netfilter/firewalld/78.0
 - commit: openSUSE:Factory/firewalld/34.0
   merged:
   - security:netfilter/firewalld/77.0
   - security:netfilter/firewalld/76.0
   - security:netfilter/firewalld/75.0
 - commit: openSUSE:Factory/firewalld/33.0
-  merged:
-  - security:netfilter/firewalld/79.0
-  - security:netfilter/firewalld/78.0
 - commit: openSUSE:Factory/firewalld/32.0
   merged:
   - security:netfilter/firewalld/74.0

tests/tree_test.py

@@ -71,5 +71,6 @@ class TestTreeMethods(unittest.TestCase):
     def test_firewalld_tree(self):
         self.verify_package("firewalld")
 
+
 if __name__ == "__main__":
     unittest.main()