no-mistakes(review): Apply wire setting to M:N targets and FromDirectory

Author: dmealing

agent-context/skills/metaobjects-codegen/references/wire-format.md

@@ -78,6 +78,10 @@ The generated input converters stay in every mode.
 
 - From 1.0.x, upgrade to 1.1.2 or later. With no setting, C#, Java and Kotlin keep their 1.0.x
   output. In Python and TypeScript, a decimal keeps its scale (`"12.50"`).
+- In Python this is a change: a 1.0.x router wrote a decimal as a JSON number, a float that can
+  lose digits (`12.5`). It now writes a string, Pydantic's `str(Decimal)`, which is the
+  Python-normal form. There is no float option, by decision. Update a client that read the
+  number to read the string (`"decimals": "string"` gives the canonical `"12.5"`).
 - A project already on 1.1.0 or 1.1.1 whose clients now expect strings and omitted members
   declares `"wire": { "decimals": "string", "nullMembers": "omit" }` before it moves to 1.1.2.
 - Every port's codegen drift gate (`meta verify --codegen`, `dotnet meta verify --codegen`,

fixtures/agent-context-conformance/java-kotlin-react-tanstack/expected/.claude/skills/metaobjects-codegen/references/wire-format.md

@@ -78,6 +78,10 @@ The generated input converters stay in every mode.
 
 - From 1.0.x, upgrade to 1.1.2 or later. With no setting, C#, Java and Kotlin keep their 1.0.x
   output. In Python and TypeScript, a decimal keeps its scale (`"12.50"`).
+- In Python this is a change: a 1.0.x router wrote a decimal as a JSON number, a float that can
+  lose digits (`12.5`). It now writes a string, Pydantic's `str(Decimal)`, which is the
+  Python-normal form. There is no float option, by decision. Update a client that read the
+  number to read the string (`"decimals": "string"` gives the canonical `"12.5"`).
 - A project already on 1.1.0 or 1.1.1 whose clients now expect strings and omitted members
   declares `"wire": { "decimals": "string", "nullMembers": "omit" }` before it moves to 1.1.2.
 - Every port's codegen drift gate (`meta verify --codegen`, `dotnet meta verify --codegen`,

fixtures/agent-context-conformance/java-react/expected/.claude/skills/metaobjects-codegen/references/wire-format.md

@@ -78,6 +78,10 @@ The generated input converters stay in every mode.
 
 - From 1.0.x, upgrade to 1.1.2 or later. With no setting, C#, Java and Kotlin keep their 1.0.x
   output. In Python and TypeScript, a decimal keeps its scale (`"12.50"`).
+- In Python this is a change: a 1.0.x router wrote a decimal as a JSON number, a float that can
+  lose digits (`12.5`). It now writes a string, Pydantic's `str(Decimal)`, which is the
+  Python-normal form. There is no float option, by decision. Update a client that read the
+  number to read the string (`"decimals": "string"` gives the canonical `"12.5"`).
 - A project already on 1.1.0 or 1.1.1 whose clients now expect strings and omitted members
   declares `"wire": { "decimals": "string", "nullMembers": "omit" }` before it moves to 1.1.2.
 - Every port's codegen drift gate (`meta verify --codegen`, `dotnet meta verify --codegen`,

fixtures/agent-context-conformance/python/expected/.claude/skills/metaobjects-codegen/references/wire-format.md

@@ -78,6 +78,10 @@ The generated input converters stay in every mode.
 
 - From 1.0.x, upgrade to 1.1.2 or later. With no setting, C#, Java and Kotlin keep their 1.0.x
   output. In Python and TypeScript, a decimal keeps its scale (`"12.50"`).
+- In Python this is a change: a 1.0.x router wrote a decimal as a JSON number, a float that can
+  lose digits (`12.5`). It now writes a string, Pydantic's `str(Decimal)`, which is the
+  Python-normal form. There is no float option, by decision. Update a client that read the
+  number to read the string (`"decimals": "string"` gives the canonical `"12.5"`).
 - A project already on 1.1.0 or 1.1.1 whose clients now expect strings and omitted members
   declares `"wire": { "decimals": "string", "nullMembers": "omit" }` before it moves to 1.1.2.
 - Every port's codegen drift gate (`meta verify --codegen`, `dotnet meta verify --codegen`,

fixtures/agent-context-conformance/ts-react-tanstack/expected/.claude/skills/metaobjects-codegen/references/wire-format.md

@@ -78,6 +78,10 @@ The generated input converters stay in every mode.
 
 - From 1.0.x, upgrade to 1.1.2 or later. With no setting, C#, Java and Kotlin keep their 1.0.x
   output. In Python and TypeScript, a decimal keeps its scale (`"12.50"`).
+- In Python this is a change: a 1.0.x router wrote a decimal as a JSON number, a float that can
+  lose digits (`12.5`). It now writes a string, Pydantic's `str(Decimal)`, which is the
+  Python-normal form. There is no float option, by decision. Update a client that read the
+  number to read the string (`"decimals": "string"` gives the canonical `"12.5"`).
 - A project already on 1.1.0 or 1.1.1 whose clients now expect strings and omitted members
   declares `"wire": { "decimals": "string", "nullMembers": "omit" }` before it moves to 1.1.2.
 - Every port's codegen drift gate (`meta verify --codegen`, `dotnet meta verify --codegen`,

fixtures/agent-context-conformance/ts-requirements/expected/.claude/skills/metaobjects-codegen/references/wire-format.md

@@ -78,6 +78,10 @@ The generated input converters stay in every mode.
 
 - From 1.0.x, upgrade to 1.1.2 or later. With no setting, C#, Java and Kotlin keep their 1.0.x
   output. In Python and TypeScript, a decimal keeps its scale (`"12.50"`).
+- In Python this is a change: a 1.0.x router wrote a decimal as a JSON number, a float that can
+  lose digits (`12.5`). It now writes a string, Pydantic's `str(Decimal)`, which is the
+  Python-normal form. There is no float option, by decision. Update a client that read the
+  number to read the string (`"decimals": "string"` gives the canonical `"12.5"`).
 - A project already on 1.1.0 or 1.1.1 whose clients now expect strings and omitted members
   declares `"wire": { "decimals": "string", "nullMembers": "omit" }` before it moves to 1.1.2.
 - Every port's codegen drift gate (`meta verify --codegen`, `dotnet meta verify --codegen`,

server/csharp/MetaObjects.Conformance.Tests/MetadataLocationTests.cs

@@ -120,12 +120,24 @@ public void FromDirectory_with_a_registry_applies_the_projects_naming()
         Assert.Equal(new PhysicalNaming(ColumnNamingStrategy.Literal, TableNamingRule.Literal), result.Root.PhysicalNaming);
     }
 
+    [Fact]
+    public void FromDirectory_with_a_registry_applies_the_projects_wire()
+    {
+        WriteConfig("""{ "schema_version": 1, "wire": { "decimals": "string", "nullMembers": "omit" } }""");
+
+        var result = MetaObjects.Loader.MetaDataLoader.FromDirectory(
+            MetaDir, MetaObjects.Provider.ComposeRegistry(MetaObjects.CoreTypes.LibraryProviders), libraries: ["iam"], strict: true);
+
+        Assert.Equal(new WireFormat(DecimalWireForm.String, NullMemberForm.Omit), result.Root.WireFormat);
+    }
+
     [Fact]
     public void FromDirectory_without_a_project_config_keeps_the_default()
     {
         var result = MetaObjects.Loader.MetaDataLoader.FromDirectory(
             MetaDir, MetaObjects.Provider.ComposeRegistry(MetaObjects.CoreTypes.LibraryProviders), libraries: ["iam"]);
 
         Assert.Equal(PhysicalNaming.Default, result.Root.PhysicalNaming);
+        Assert.Equal(WireFormat.Default, result.Root.WireFormat);
     }
 }

server/csharp/MetaObjects/Loader/MetaDataLoader.cs

@@ -155,7 +155,11 @@ public static LoadResult FromDirectory(string directory, TypeRegistry registry,
         // ADR-0058: the project's `naming` applies to a directory load too, as the JVM
         // fromDirectory does. Without this, a host that composes its own registry (the
         // documented way to add a provider) silently got snake_case whatever the project says.
-        if (Config.MetadataLocation.ConfigFor(directory) is { } cfg) result.Root.PhysicalNaming = cfg.Naming;
+        if (Config.MetadataLocation.ConfigFor(directory) is { } cfg)
+        {
+            result.Root.PhysicalNaming = cfg.Naming;
+            result.Root.WireFormat = cfg.Wire;
+        }
         return result;
     }
 

server/python/src/metaobjects/codegen/generators/router_generator.py

@@ -285,8 +285,8 @@ def _field_shape(f: MetaField, seen: frozenset[str]) -> dict[str, Any] | None:
     return {"m": shape} if f.sub_type == fc.FIELD_SUBTYPE_MAP else shape
 
 
-def _wire_lines(entities: list[MetaObject], wire: WireFormat) -> list[str]:
-    """The ``_WIRE`` constant every response is written through: the project's ``wire``
+def _wire_lines(entities: list[MetaObject], wire: WireFormat, name: str = "_WIRE") -> list[str]:
+    """The *name* constant a response of *entities* is written through: the project's ``wire``
     setting (ADR-0019 Amendment 2) and, when ``nullMembers`` is not ``native``, the declared
     members of each value-object field of *entities* (the first declaration of a name wins)."""
     shapes: dict[str, Any] = {}
@@ -298,7 +298,26 @@ def _wire_lines(entities: list[MetaObject], wire: WireFormat) -> list[str]:
     args = f'decimals="{wire.decimals}", null_members="{wire.null_members}"'
     if shapes:
         args += f", shapes={shapes!r}"
-    return ["", "", f"_WIRE = WireOutput({args})"]
+    return ["", "", f"{name} = WireOutput({args})"]
+
+
+def _m2m_wire_name(target: str) -> str:
+    """The wire constant an M:N traversal onto *target* writes the target's rows through."""
+    return f"_WIRE_{_snake_case(target).upper()}"
+
+
+def _m2m_wire_lines(
+    descriptors: list[M2mDescriptor], object_index: dict[str, MetaObject], wire: WireFormat
+) -> list[str]:
+    """One :func:`_m2m_wire_name` constant per distinct M:N target, shaped by the TARGET's
+    value-object fields (and its TPH subtypes' when the target is a discriminator base)."""
+    lines: list[str] = []
+    for name in dict.fromkeys(d.target_entity for d in descriptors):
+        target = next(o for o in object_index.values() if o.name == name)
+        plan = tph_plan_for(target, object_index)
+        entities = [target, *(st.entity for st in plan.subtypes)] if plan is not None else [target]
+        lines.extend(_wire_lines(entities, wire, _m2m_wire_name(name)))
+    return lines
 
 
 def _decimal_limits_lines(entities: list[MetaObject]) -> list[str]:
@@ -877,7 +896,8 @@ def _emit_m2m_route(
             f"    repo: Annotated[{repo_class}, Depends(get_repository)],",
             ") -> list[Any]:",
             f"    return render_wire(repo.find_related_{d.relation_name}"
-            f"({pk_param}{_target_subtype_arg(d, {d.target_discriminator})}), _WIRE)",
+            f"({pk_param}{_target_subtype_arg(d, {d.target_discriminator})}), "
+            f"{_m2m_wire_name(d.target_entity)})",
         ]
 
     def _emit_tph_m2m_route(
@@ -934,7 +954,8 @@ def _emit_tph_m2m_route(
             ]
         lines.append(
             f"    return render_wire(repo.find_related_{d.relation_name}"
-            f"({subtype_expr}, {pk_param}{_target_subtype_arg(d, target_discs)}), _WIRE)"
+            f"({subtype_expr}, {pk_param}{_target_subtype_arg(d, target_discs)}), "
+            f"{_m2m_wire_name(d.target_entity)})"
         )
         return lines
 
@@ -1159,6 +1180,11 @@ def _render_tph_router(
         parts.append(f"_DECIMAL_FIELDS: frozenset[str] = {decimal_set_body}")
         parts.extend(_decimal_limits_lines([entity, *(st.entity for st in plan.subtypes)]))
         parts.extend(_wire_lines([entity, *(st.entity for st in plan.subtypes)], wire))
+        parts.extend(_m2m_wire_lines(
+            [*base_m2m, *(d for st in plan.subtypes for d in sub_m2m[st.entity.name])],
+            object_index,
+            wire,
+        ))
         parts.append("")
         parts.append("")
         parts.extend(_JSON_BODY_LINES)
@@ -1536,6 +1562,7 @@ def render_router(
         parts.append(f"_DECIMAL_FIELDS: frozenset[str] = {decimal_set_body}")
         parts.extend(_decimal_limits_lines([entity]))
         parts.extend(_wire_lines([entity], wire))
+        parts.extend(_m2m_wire_lines(m2m, object_index or {}, wire))
         parts.append("")
         parts.append("")
         parts.extend(_JSON_BODY_LINES)

server/python/src/metaobjects/codegen/runtime/decimal_wire.py

@@ -291,8 +291,8 @@ class WireOutput:
 
 
 def render_wire(value: Any, wire: WireOutput) -> Any:
-    """A response *value* (a row, a list of rows, the ``{"rows", "total"}`` envelope, a
-    Pydantic model) in the form *wire* asks for. Input rules do not depend on *wire*."""
+    """A response *value* (a row, a list of rows, a Pydantic model) in the form *wire* asks
+    for. Input rules do not depend on *wire*."""
     if wire.null_members != "native" and wire.shapes:
         value = _shape_members(value, wire)
     return to_wire(value) if wire.decimals == "string" else to_native(value)
@@ -310,7 +310,7 @@ def _shape_members(value: Any, wire: WireOutput) -> Any:
         return value
     out: dict[str, Any] = {}
     for k, v in value.items():
-        out[k] = _shape_vo(v, wire.shapes[k], wire.null_members) if k in wire.shapes else _shape_members(v, wire)
+        out[k] = _shape_vo(v, wire.shapes[k], wire.null_members) if k in wire.shapes else v
     return out