shape_materialize.py: RULESET_HINT names the run's tracking branch where it named main, as the pull request's base and the ref the scaffold and the family holder pushed (#324)

scaffold-project.py

@@ -1205,7 +1205,10 @@ def _seed_legs(args, values: dict, names: dict, repositories: dict,
             except CommandFailed as exc:
                 print(exc.loudly(f"pushing the {role} leg"), file=sys.stderr)
                 print(RULESET_HINT.format(work=work, repo=repositories[role],
-                                          role=role), file=sys.stderr)
+                                          role=role,
+                                          local=args.tracking_branch,
+                                          tracking=args.tracking_branch),
+                      file=sys.stderr)
                 return None
         print(f"  {role:<9} {commit[:12]} tree {leg_digests[role][:12]}… "
               f"-> {urls[role]}")
@@ -1321,7 +1324,10 @@ def _build_assembly_root(args, values: dict, names: dict, repositories: dict,
             print(exc.loudly("pushing the assembly root"), file=sys.stderr)
             print(RULESET_HINT.format(work=assembly,
                                       repo=repositories["assembly"],
-                                      role="assembly"), file=sys.stderr)
+                                      role="assembly",
+                                      local=args.tracking_branch,
+                                      tracking=args.tracking_branch),
+                  file=sys.stderr)
             return False
     print(f"  assembly  {run(['git', 'rev-parse', 'HEAD'], cwd=assembly)[:12]} "
           f"-> {urls['assembly']}")

scripts/family.py

@@ -1013,7 +1013,10 @@ def _create_holder_worktree(args, work: Path, values: dict, shape_commit: str,
     except CommandFailed as exc:
         print(exc.loudly("pushing the family holder"), file=sys.stderr)
         print(RULESET_HINT.format(work=work, repo=repository,
-                                  role="family"), file=sys.stderr)
+                                  role="family",
+                                  local=args.tracking_branch,
+                                  tracking=args.tracking_branch),
+              file=sys.stderr)
         return 2
     return None
 

scripts/shape_materialize.py

@@ -734,6 +734,19 @@ def loudly(self, what: str) -> str:
         )
 
 
+#: Two fields name a branch, and they are NOT the same thing (#324):
+#:   `{tracking}` is the run's tracking branch (`--tracking-branch`): the
+#:   branch of the REMOTE the refused push targeted, and so the base a
+#:   seeding pull request lands on.
+#:   `{local}` is the ref in `{work}` that the refused push carried. Each
+#:   caller -- the scaffold's legs and assembly root, the family holder --
+#:   pushed the tracking branch BY NAME from a clone made on it, so each
+#:   passes the tracking branch for both; a push of `HEAD:` would name `HEAD`.
+#:   An adoption prints its own `ADOPT_RULESET_HINT` (`adopt-project.py`,
+#:   #177), which names the tracking branch the same way and no command.
+#: Every caller passes both, after `checked_value` has admitted the tracking
+#: branch, so each is a safe argument and neither is quoted here. A call that
+#: leaves one out fails `tests/test_ruleset_hint_tracking_branch.py`.
 RULESET_HINT = """
 If the organisation applies a ruleset requiring changes to arrive by pull
 request, a direct push to the default branch is refused BY DESIGN and must not
@@ -742,8 +755,8 @@ def loudly(self, what: str) -> str:
   (1) have an operator holding the bypass right seed the default branch once,
       then re-run this scaffold; or
   (2) push a seed BRANCH and open a pull request:
-          git -C {work} push -u origin main:seed/scaffold
-          gh pr create --repo {repo} --base main --head seed/scaffold \\
+          git -C {work} push -u origin {local}:seed/scaffold
+          gh pr create --repo {repo} --base {tracking} --head seed/scaffold \\
               --title 'Seed the {role} leg' --body 'Scaffolded shape.'
 
 NOTHING has been rolled back. What already exists is listed above; delete it