pydantic 2.13.4: Replace pydantic v1 parse_obj/dict with the v2 model_validate/model_dump API

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pydantic==2.13.4
pydantic-core==2.46.4
typing-extensions==4.16.0
annotated-types==0.8.0
typing-inspection==0.4.4

"""pydantic v2 validation, with the v1 names that no longer exist."""

from pydantic import BaseModel, Field, ValidationError


class Peer(BaseModel):
    peer_id: str = Field(min_length=3)
    port: int = Field(ge=1, le=65535)
    tags: list[str] = []


def validate(payload):
    """Validate a dict into a Peer.

    v2 renamed the whole surface: parse_obj -> model_validate,
    parse_raw -> model_validate_json, .dict() -> .model_dump(),
    .json() -> .model_dump_json(). The old names still resolve as
    deprecated shims, so a v1 codebase keeps running after the upgrade and
    the migration looks finished when it is not — the warnings are the
    only signal, and they are easy to filter away.
    """
    return Peer.model_validate(payload)


def errors_for(payload):
    """Return the structured error list for an invalid payload."""
    try:
        Peer.model_validate(payload)
    except ValidationError as exc:
        return exc.errors()
    return []

import os
import sys
import warnings

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
from src.models import Peer, errors_for, validate

peer = validate({"peer_id": "ed25519:abc", "port": 48620, "tags": ["blob"]})
assert peer.peer_id == "ed25519:abc"
assert peer.port == 48620

# v2 returns plain data from model_dump; .dict() is gone.
assert validate({"peer_id": "abc", "port": 1}).model_dump() == {
    "peer_id": "abc", "port": 1, "tags": []
}
# The v1 names still EXIST in v2 as deprecated shims — they do not raise
# AttributeError, they warn. That is why a v1 codebase keeps working after
# the upgrade while quietly accruing deprecation debt, and why "it still
# runs" is not evidence that the migration is done.
with warnings.catch_warnings(record=True) as caught:
    warnings.simplefilter("always")
    legacy = Peer.parse_obj({"peer_id": "ed25519:ghi", "port": 2})
    assert legacy.port == 2
    assert any(issubclass(w.category, DeprecationWarning) for w in caught),         "parse_obj should warn in v2"

errs = errors_for({"peer_id": "ab", "port": 99999})
codes = sorted(e["type"] for e in errs)
assert len(errs) == 2, errs
assert all("loc" in e and "msg" in e for e in errs)
assert codes == ["less_than_equal", "string_too_short"], codes

print("CONTRACT PASS: pydantic v2 validated, dumped and reported typed errors")