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Iterator error contexts lose parent links and absolute paths #1584
Description
Problem
Passing an iterator as ValidationError(context=...) retains its children, but does not set their parent. The iterator is consumed by self.context = list(context), then iterated again when assigning parents. This also affects SchemaError.
from jsonschema.exceptions import ValidationError
child = ValidationError("child", path=["name"], schema_path=[0, "type"])
parent = ValidationError(
"parent",
path=["record"],
schema_path=["properties", "record", "anyOf"],
context=iter([child]),
)
print(parent.context == [child]) # True
print(child.parent is parent) # False (expected True)
print(child.json_path) # $.name (expected $.record.name)Lists and tuples assign the parent correctly. Setting parents from the stored self.context instead of the original iterable should preserve the same behavior for one-shot iterators.
Reproduced on main (51cd75e39), macOS, Python 3.12.13. A regression test fails for iterator contexts with both error classes and passes for list/tuple contexts.
Investigated with Codex assistance.
Activity
GreedyC commentedon Oct 2, 2026
A one-line fix and regression tests are ready at GreedyC/jsonschema@19ddb83. The full suite passes on Python 3.10 and 3.12 (8,298 passed, 232 skipped each), plus Ruff and both mypy checks.
PR creation is restricted to collaborators in this repository, so no PR was opened. Leaving the patch here in case it is useful; the iterator tests fail before the fix and cover both error classes.
DawnofGenX commentedon Oct 5, 2026
I'd like to work on this.
The issue is that passing an iterator as
ValidationError(context=...)retains its children, but does not set theirparent. The iterator is consumed byself.context = list(context), then iterated again when assigning parents.The fix is to set parents from the stored
self.contextinstead of the original iterable, which should preserve the same behavior for one-shot iterators.I'll add a regression test and implement the fix.
simpleqt commentedon Oct 6, 2026
Confirmed on
main(9eeeddb), including theSchemaErrorcase (shared_Error.__init__).I have a prepared fix and regression test on a branch of my fork: main...simpleqt:jsonschema:sq/iterator-context-parents
The change iterates the already-stored
self.contextinstead of the original one-shot iterable:self.context = list(context) ... - for error in context: + for error in self.context: error.parent = selfAttempting to open a pull request from the fork is currently rejected with "does not have the correct permissions to execute CreatePullRequest", which looks like repository interaction limits — so if that's intentional and in effect, feel free to take the patch from the branch directly (single commit,
ruffclean, new test inTestErrorInitReprStrfails before / passes after, full suite otherwise unchanged: 7830 passed, 700 skipped).