fix(types): widen canceled Literal[True]=True to Literal[True]|None=None on request types

scripts/post_generate_fixes.py

@@ -10,6 +10,7 @@
 3. Fixes BrandManifest forward references
 4. Adds deprecated=True to fields marked deprecated in JSON schema
 5. Unwraps specified RootModel unions to plain Union type aliases (#155)
+6. Widens canceled: Literal[True] = True on request types to | None = None (#641)
 """
 
 from __future__ import annotations
@@ -1053,6 +1054,68 @@ def _ensure_sequence_import(content: str) -> str:
     return "from collections.abc import Sequence\n\n" + content
 
 
+# Matches the four request-type 'canceled: Literal[True] = True' emissions.
+# datamodel-codegen emits '= True' directly from "const": true boolean
+# schema properties — it is NOT produced by inject_literal_discriminator_defaults()
+# (which already skips bool-valued Literals). Each match rewrites only the
+# annotation and the default; the Field description and the rest of the class
+# are untouched. The regex is inherently idempotent: 'Literal[True] | None,'
+# does not match 'Literal[True],' so a second pass is a no-op.
+_CANCELED_FIELD_RE = re.compile(
+    r"(    canceled: Annotated\[\n        )"
+    r"Literal\[True\]"
+    r"(,\n        Field\(\n            description='Cancel[^']*'\n        \),\n    \])"
+    r" = True"
+)
+
+
+def fix_canceled_literal_defaults() -> None:
+    """Widen ``canceled: Literal[True] = True`` on request types to ``Literal[True] | None = None``.
+
+    Issue #641: the generated ``= True`` default silently cancels media buys /
+    packages when a buyer omits the field from an update request. Changing to
+    ``Literal[True] | None = None`` preserves wire semantics (the field still
+    only accepts ``true`` when present) while making omission non-destructive.
+
+    Response-side ``canceled: bool | None = False`` fields (status indicators
+    like ``core/package.py``) are out of scope — their default is already safe.
+
+    Root cause: ``datamodel-codegen`` emits ``= True`` from the schema's
+    ``"const": true`` boolean property. This function corrects that misfire for
+    the four request-type emissions listed below.
+    """
+    targets = [
+        OUTPUT_DIR / "media_buy/update_media_buy_request.py",
+        OUTPUT_DIR / "media_buy/package_update.py",
+        OUTPUT_DIR / "bundled/media_buy/update_media_buy_request.py",
+    ]
+
+    total_fixed = 0
+    for py_file in targets:
+        if not py_file.exists():
+            print(f"  {py_file.relative_to(OUTPUT_DIR)}: not found (skipping)")
+            continue
+
+        source = py_file.read_text()
+        new_source, count = _CANCELED_FIELD_RE.subn(
+            r"\1Literal[True] | None\2 = None",
+            source,
+        )
+
+        if count == 0:
+            print(f"  {py_file.relative_to(OUTPUT_DIR)}: no destructive canceled defaults found")
+            continue
+
+        py_file.write_text(new_source)
+        total_fixed += count
+        print(f"  {py_file.relative_to(OUTPUT_DIR)}: fixed {count} canceled field(s)")
+
+    if total_fixed > 0:
+        print(f"  ✓ Widened {total_fixed} canceled Literal[True] default(s) to None")
+    else:
+        print("  No canceled field defaults needed fixing")
+
+
 def main():
     """Apply all post-generation fixes."""
     print("Applying post-generation fixes...")
@@ -1071,6 +1134,7 @@ def main():
     restore_format_category_deprecation_shim()
     inject_literal_discriminator_defaults()
     widen_extension_point_lists_to_sequence()
+    fix_canceled_literal_defaults()
 
     print("\n✓ Post-generation fixes complete\n")
 

src/adcp/types/generated_poc/bundled/media_buy/update_media_buy_request.py

@@ -4775,11 +4775,11 @@ class Package(AdCPBaseModel):
         Field(description='Pause/resume specific package (true = paused, false = active)'),
     ] = None
     canceled: Annotated[
-        Literal[True],
+        Literal[True] | None,
         Field(
             description='Cancel this specific package. Cancellation is irreversible — canceled packages stop delivery and cannot be reactivated. Sellers MAY reject with NOT_CANCELLABLE.'
         ),
-    ] = True
+    ] = None
     cancellation_reason: Annotated[
         str | None, Field(description='Reason for canceling this package.', max_length=500)
     ] = None
@@ -7575,11 +7575,11 @@ class UpdateMediaBuyRequest(AdCPBaseModel):
         Field(description='Pause/resume the entire media buy (true = paused, false = active)'),
     ] = None
     canceled: Annotated[
-        Literal[True],
+        Literal[True] | None,
         Field(
             description='Cancel the entire media buy. Cancellation is irreversible — canceled media buys cannot be reactivated. Sellers MAY reject with NOT_CANCELLABLE if the media buy cannot be canceled in its current state.'
         ),
-    ] = True
+    ] = None
     cancellation_reason: Annotated[
         str | None,
         Field(

src/adcp/types/generated_poc/media_buy/package_update.py

@@ -97,11 +97,11 @@ class PackageUpdate(AdCPBaseModel):
         Field(description='Pause/resume specific package (true = paused, false = active)'),
     ] = None
     canceled: Annotated[
-        Literal[True],
+        Literal[True] | None,
         Field(
             description='Cancel this specific package. Cancellation is irreversible — canceled packages stop delivery and cannot be reactivated. Sellers MAY reject with NOT_CANCELLABLE.'
         ),
-    ] = True
+    ] = None
     cancellation_reason: Annotated[
         str | None, Field(description='Reason for canceling this package.', max_length=500)
     ] = None

src/adcp/types/generated_poc/media_buy/update_media_buy_request.py

@@ -50,11 +50,11 @@ class UpdateMediaBuyRequest(AdCPBaseModel):
         Field(description='Pause/resume the entire media buy (true = paused, false = active)'),
     ] = None
     canceled: Annotated[
-        Literal[True],
+        Literal[True] | None,
         Field(
             description='Cancel the entire media buy. Cancellation is irreversible — canceled media buys cannot be reactivated. Sellers MAY reject with NOT_CANCELLABLE if the media buy cannot be canceled in its current state.'
         ),
-    ] = True
+    ] = None
     cancellation_reason: Annotated[
         str | None,
         Field(

tests/test_canceled_literal_default.py

@@ -0,0 +1,146 @@
+"""Tests for issue #641 — canceled: Literal[True] = True destructive default.
+
+UpdateMediaBuyRequest and PackageUpdate previously had ``canceled: Literal[True] = True``,
+meaning any call that omitted the field silently triggered irreversible cancellation.
+The fix widens the type to ``Literal[True] | None = None`` so omission is non-destructive.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+
+class TestUpdateMediaBuyRequestCanceledDefault:
+    """UpdateMediaBuyRequest.canceled must default to None (non-destructive)."""
+
+    _ACCOUNT_KWARGS = {
+        "account": {"account_id": "acc_test_001"},
+        "media_buy_id": "mbuy-123",
+        "idempotency_key": "a" * 16,
+    }
+
+    def test_canceled_defaults_to_none_when_omitted(self) -> None:
+        from adcp.types.generated_poc.media_buy.update_media_buy_request import (
+            UpdateMediaBuyRequest,
+        )
+
+        req = UpdateMediaBuyRequest(**self._ACCOUNT_KWARGS)
+        assert req.canceled is None
+
+    def test_canceled_true_still_accepted(self) -> None:
+        from adcp.types.generated_poc.media_buy.update_media_buy_request import (
+            UpdateMediaBuyRequest,
+        )
+
+        req = UpdateMediaBuyRequest(**self._ACCOUNT_KWARGS, canceled=True)
+        assert req.canceled is True
+
+    def test_canceled_none_excluded_from_wire_payload(self) -> None:
+        """When canceled is None, model_dump(exclude_none=True) omits it — no cancellation on wire."""
+        from adcp.types.generated_poc.media_buy.update_media_buy_request import (
+            UpdateMediaBuyRequest,
+        )
+
+        req = UpdateMediaBuyRequest(**self._ACCOUNT_KWARGS)
+        payload = req.model_dump(mode="json", exclude_none=True)
+        assert "canceled" not in payload
+
+    def test_canceled_true_present_in_wire_payload(self) -> None:
+        """Explicit canceled=True must appear in the wire payload to trigger cancellation."""
+        from adcp.types.generated_poc.media_buy.update_media_buy_request import (
+            UpdateMediaBuyRequest,
+        )
+
+        req = UpdateMediaBuyRequest(**self._ACCOUNT_KWARGS, canceled=True)
+        payload = req.model_dump(mode="json", exclude_none=True)
+        assert payload["canceled"] is True
+
+    def test_canceled_false_rejected(self) -> None:
+        """Literal[True] still rejects False — the field is a one-way commit signal."""
+        from pydantic import ValidationError
+
+        from adcp.types.generated_poc.media_buy.update_media_buy_request import (
+            UpdateMediaBuyRequest,
+        )
+
+        with pytest.raises(ValidationError):
+            UpdateMediaBuyRequest(**self._ACCOUNT_KWARGS, canceled=False)  # type: ignore[arg-type]
+
+
+class TestPackageUpdateCanceledDefault:
+    """PackageUpdate.canceled must default to None (non-destructive)."""
+
+    def test_canceled_defaults_to_none_when_omitted(self) -> None:
+        from adcp.types.generated_poc.media_buy.package_update import PackageUpdate
+
+        pkg = PackageUpdate(package_id="pkg-1")
+        assert pkg.canceled is None
+
+    def test_canceled_true_still_accepted(self) -> None:
+        from adcp.types.generated_poc.media_buy.package_update import PackageUpdate
+
+        pkg = PackageUpdate(package_id="pkg-1", canceled=True)
+        assert pkg.canceled is True
+
+    def test_canceled_none_excluded_from_wire_payload(self) -> None:
+        from adcp.types.generated_poc.media_buy.package_update import PackageUpdate
+
+        pkg = PackageUpdate(package_id="pkg-1")
+        payload = pkg.model_dump(mode="json", exclude_none=True)
+        assert "canceled" not in payload
+
+    def test_canceled_true_present_in_wire_payload(self) -> None:
+        from adcp.types.generated_poc.media_buy.package_update import PackageUpdate
+
+        pkg = PackageUpdate(package_id="pkg-1", canceled=True)
+        payload = pkg.model_dump(mode="json", exclude_none=True)
+        assert payload["canceled"] is True
+
+
+class TestFixIdempotency:
+    """The post-gen fix must be idempotent — running it twice produces the same output."""
+
+    def test_fix_is_idempotent_on_synthesized_source(self) -> None:
+        from scripts.post_generate_fixes import _CANCELED_FIELD_RE
+
+        already_fixed = (
+            "    canceled: Annotated[\n"
+            "        Literal[True] | None,\n"
+            "        Field(\n"
+            "            description='Cancel this specific package. Cancellation is irreversible"
+            " — canceled packages stop delivery and cannot be reactivated."
+            " Sellers MAY reject with NOT_CANCELLABLE.'\n"
+            "        ),\n"
+            "    ] = None\n"
+        )
+
+        result, count = _CANCELED_FIELD_RE.subn(
+            r"\1Literal[True] | None\2 = None",
+            already_fixed,
+        )
+        assert count == 0, "fix must not re-apply to already-widened source"
+        assert result == already_fixed
+
+    def test_fix_matches_destructive_source(self) -> None:
+        from scripts.post_generate_fixes import _CANCELED_FIELD_RE
+
+        destructive = (
+            "    canceled: Annotated[\n"
+            "        Literal[True],\n"
+            "        Field(\n"
+            "            description='Cancel this specific package. Cancellation is irreversible"
+            " — canceled packages stop delivery and cannot be reactivated."
+            " Sellers MAY reject with NOT_CANCELLABLE.'\n"
+            "        ),\n"
+            "    ] = True\n"
+        )
+
+        result, count = _CANCELED_FIELD_RE.subn(
+            r"\1Literal[True] | None\2 = None",
+            destructive,
+        )
+        assert count == 1
+        assert "Literal[True] | None," in result
+        assert "] = None" in result
+        assert "Literal[True]," not in result
+        assert "] = True" not in result