fix(compilers/openapi): fill allOf position constraints

compilers/openapi/conformance_test.go

@@ -172,6 +172,7 @@ func conformanceCases() []conformanceCase {
 		{"allof-ref-branch-siblings", assertAllOfRefBranchSiblings, []string{"intersection", "untagged-unions"}},
 		{"allof-boolean-branch", assertAllOfBooleanBranch, []string{"intersection"}},
 		{"allof-conflicting-type", assertAllOfConflictingType, nil},
+		{"allof-position-constraints", assertAllOfPositionConstraints, []string{"intersection"}},
 		{"oneof-discriminated", assertOneOfDiscriminated, []string{"tagged-unions"}},
 		{"discriminator-inheritance", assertDiscriminatorInheritance, []string{"tagged-unions", "inheritance"}},
 		{"discriminator-default-mapping", assertDiscriminatorDefaultMapping, []string{"tagged-unions"}},
@@ -820,6 +821,9 @@ func assertAllOfOneOfCooccurrence(t *testing.T, doc *ir.Document, _ []ir.Diagnos
 		assert.Equal(t, namedID("Base"), v.Base.Target)
 		require.Len(t, v.Mixins, 1)
 		assert.Equal(t, namedID(branch), v.Mixins[0].Target)
+		require.NotNil(t, v.Constraints, "the enclosing schema's own minProperties rides on every variant too (GitHub #407)")
+		require.NotNil(t, v.Constraints.MinProps)
+		assert.Equal(t, int64(2), *v.Constraints.MinProps)
 	}
 
 	mixed, ok := doc.Types[namedID("MixedKinds")].(*ir.Model)
@@ -884,6 +888,31 @@ func assertInlineBranchHint(t *testing.T, doc *ir.Document) {
 		"the outside reference resolves to that same node rather than hoisting a second")
 }
 
+// assertAllOfPositionConstraints pins GitHub #407: a value constraint written
+// beside an allOf composing position reaches the same ir.Model.Constraints
+// field a plain object's does, rather than falling to Unmodeled under a
+// diagnostic that claims the node has no home for it — the node demonstrably
+// does, since ViaModel's sibling proves the field exists and is read.
+func assertAllOfPositionConstraints(t *testing.T, doc *ir.Document, diags []ir.Diagnostic) {
+	viaModel, ok := doc.Types[namedID("ViaModel")].(*ir.Model)
+	require.True(t, ok)
+	require.NotNil(t, viaModel.Constraints)
+	require.NotNil(t, viaModel.Constraints.MinProps)
+	assert.Equal(t, int64(2), *viaModel.Constraints.MinProps)
+
+	viaAllOf, ok := doc.Types[namedID("ViaAllOf")].(*ir.Model)
+	require.True(t, ok)
+	require.NotNil(t, viaAllOf.Base, "the sole allOf $ref still becomes Base")
+	assert.Equal(t, namedID("Base"), viaAllOf.Base.Target)
+	require.NotNil(t, viaAllOf.Constraints, "the composing position's own minProperties reaches the model it built, exactly as a plain object's does")
+	require.NotNil(t, viaAllOf.Constraints.MinProps)
+	assert.Equal(t, int64(2), *viaAllOf.Constraints.MinProps)
+	assert.NotContains(t, viaAllOf.Unmodeled, "openapi:minProperties",
+		"minProperties has a home now, so it is not also kept verbatim")
+	assert.Empty(t, diagsAt(diags, diag.DegradedConstruct, "/components/schemas/ViaAllOf"),
+		"and no diagnostic claims the node has no home for it")
+}
+
 func assertOneOfDiscriminated(t *testing.T, doc *ir.Document, _ []ir.Diagnostic) {
 	pet, ok := doc.Types[namedID("Pet")].(*ir.Union)
 	require.True(t, ok, "oneOf survives as a Union node, never collapsed")

compilers/openapi/internal/schema/compose.go

@@ -27,10 +27,19 @@ import (
 // hierarchy) becomes Base; other $refs become Mixins in source order; inline
 // branches contribute their properties, each carrying provenance into the
 // allOf branch it came from.
+//
+// The composing position's own value constraints (minProperties, maxProperties,
+// ...) are read the same way lowerModel reads a plain object's: a bound written
+// beside the allOf constrains the composed model exactly as one written beside
+// `type: object` constrains it, so it belongs on the same field rather than
+// falling to Unmodeled for want of a fill this lowering forgot to do (GitHub
+// #407).
 func lowerAllOf(c lowering.Ctx, ts *compile.Types, anchors *AnchorIndex, depth int, s *oas3.Schema, pointer, hint string) (ir.TypeID, []ir.Diagnostic) {
 	var diags []ir.Diagnostic
 	id := internNode(c, ts, pointer, hint, func(common ir.TypeCommon) ir.TypeDef {
-		m := &ir.Model{TypeCommon: common}
+		cons, consDiags := schemaConstraints(c, &common.Unmodeled, s, pointer)
+		diags = append(diags, consDiags...)
+		m := &ir.Model{TypeCommon: common, Constraints: cons}
 		diags = append(diags, fillAllOf(c, ts, anchors, depth, m, s, pointer)...)
 		diags = append(diags, fillModelProperties(c, ts, anchors, depth, m, s, pointer)...)
 		diags = append(diags, applyCompositionRequired(c, m, s, pointer)...)
@@ -976,9 +985,17 @@ func composedVariantNullable(body *oas3.Schema, branch ir.TypeRef) bool {
 // and any shared additionalProperties node are the single set the source
 // declared, named after the enclosing schema rather than after whichever branch
 // happened to build them first.
+//
+// The enclosing schema's own value constraints are read the same way, for the
+// same reason lowerAllOf reads them (GitHub #407): `S ∧ (X | Y)` distributes to
+// `(S ∧ X) | (S ∧ Y)`, and a bound S declares constrains both sides of that
+// disjunction, so each variant carries its own copy rather than the bound
+// reaching no field at all — this path never runs the pointer's own census, so
+// nothing else stamps it.
 func buildComposedVariant(c lowering.Ctx, ts *compile.Types, anchors *AnchorIndex, depth int, body composedBody, branch ir.TypeID, common ir.TypeCommon) (ir.TypeDef, []ir.Diagnostic) {
-	m := &ir.Model{TypeCommon: common}
-	diags := fillAllOf(c, ts, anchors, depth, m, body.schema, body.pointer)
+	cons, diags := schemaConstraints(c, &common.Unmodeled, body.schema, body.pointer)
+	m := &ir.Model{TypeCommon: common, Constraints: cons}
+	diags = append(diags, fillAllOf(c, ts, anchors, depth, m, body.schema, body.pointer)...)
 	diags = append(diags, fillModelProperties(c, ts, anchors, depth, m, body.schema, body.pointer)...)
 	diags = append(diags, applyCompositionRequired(c, m, body.schema, body.pointer)...)
 	diags = append(diags, fillAdditional(c, ts, anchors, depth, m, body.schema, body.pointer, body.hint)...)

compilers/openapi/internal/schema/schema.go

@@ -837,11 +837,13 @@ func typeShapedBy(td ir.TypeDef, st oas3.SchemaType) bool {
 // anything that missed the field here reaches no field anywhere.
 //
 // Having the field is not reading it, so the two node kinds that have one ask
-// whether it was filled: a Model lowerAllOf composed carries no constraints at
-// all, where one lowerModel built carries whatever schemaConstraints read. A
-// List is absent for the stronger reason — lowerArray fills its Constraints from
-// listConstraints, whose collection bounds valueConstraintKeywords deliberately
-// excludes, so no value constraint ever reaches it however full the field looks.
+// whether it was filled: a Model carries whatever schemaConstraints read,
+// whether lowerModel or lowerAllOf built it — both fill Constraints the same
+// way (GitHub #407), so the composing position's own bound has the same home a
+// plain object's does. A List is absent for the stronger reason — lowerArray
+// fills its Constraints from listConstraints, whose collection bounds
+// valueConstraintKeywords deliberately excludes, so no value constraint ever
+// reaches it however full the field looks.
 func constraintsHome(td ir.TypeDef) bool {
 	switch n := td.(type) {
 	case *ir.Scalar:

testdata/conformance/openapi/allof-oneof-cooccurrence.golden.json

@@ -79,6 +79,10 @@
           "nullable": false
         }
       ],
+      "constraints": {
+        "uniqueItems": false,
+        "minProps": 2
+      },
       "abstract": false,
       "positional": false,
       "inputOnly": false
@@ -106,6 +110,10 @@
           "nullable": false
         }
       ],
+      "constraints": {
+        "uniqueItems": false,
+        "minProps": 2
+      },
       "abstract": false,
       "positional": false,
       "inputOnly": false
@@ -597,7 +605,7 @@
     {
       "format": "openapi@3.1",
       "path": "allof-oneof-cooccurrence.yaml",
-      "hash": "9deaf845e7a310c701113bd61e60a7e0d170cbf96860921816623667813e458f"
+      "hash": "a7ad825638ecc39459061faaec4308e1f47ab61c99d30cad7b57373bbbab329a"
     }
   ]
 }

testdata/conformance/openapi/allof-oneof-cooccurrence.yaml

@@ -16,13 +16,16 @@ components:
       properties:
         b: {type: string}
     # allOf and oneOf at one level conjoin: the value satisfies Base AND exactly
-    # one of A/B. Both sides must survive (reference-learnings B11).
+    # one of A/B. Both sides must survive (reference-learnings B11). minProperties
+    # is the enclosing schema's own value constraint, distributed across both
+    # variants the same as Base is (GitHub #407).
     Combo:
       allOf:
         - {$ref: '#/components/schemas/Base'}
       oneOf:
         - {$ref: '#/components/schemas/A'}
         - {$ref: '#/components/schemas/B'}
+      minProperties: 2
     # An inline branch names no referent to conjoin Base with, so this union is
     # kept verbatim instead of half-distributed (ir-design 4.8).
     MixedKinds:

testdata/conformance/openapi/allof-position-constraints.golden.json

@@ -0,0 +1,175 @@
+{
+  "irVersion": "0.4.0",
+  "name": "AllOfPositionConstraints",
+  "version": "1.0.0",
+  "docs": {},
+  "services": [
+    {
+      "id": "s/openapi/0",
+      "name": {
+        "source": "AllOfPositionConstraints",
+        "canonical": "all_of_position_constraints"
+      },
+      "docs": {},
+      "auth": null,
+      "provenance": {
+        "source": 0
+      }
+    }
+  ],
+  "types": {
+    "t/openapi/components/schemas/Base": {
+      "kind": "model",
+      "id": "t/openapi/components/schemas/Base",
+      "name": {
+        "source": "Base",
+        "canonical": "base"
+      },
+      "anonymous": false,
+      "docs": {},
+      "sensitive": false,
+      "provenance": {
+        "source": 0,
+        "pointer": "/components/schemas/Base"
+      },
+      "properties": [
+        {
+          "id": "p/openapi/components/schemas/Base/properties/id",
+          "name": {
+            "source": "id",
+            "canonical": "id"
+          },
+          "wireName": "id",
+          "type": {
+            "target": "t/prim/string",
+            "nullable": false
+          },
+          "required": false,
+          "clientOptional": false,
+          "defaultAdded": false,
+          "visibility": {
+            "none": false
+          },
+          "flatten": false,
+          "eventHeader": false,
+          "eventPayload": false,
+          "secret": false,
+          "docs": {},
+          "provenance": {
+            "source": 0,
+            "pointer": "/components/schemas/Base/properties/id"
+          }
+        }
+      ],
+      "abstract": false,
+      "positional": false,
+      "inputOnly": false
+    },
+    "t/openapi/components/schemas/ViaAllOf": {
+      "kind": "model",
+      "id": "t/openapi/components/schemas/ViaAllOf",
+      "name": {
+        "source": "ViaAllOf",
+        "canonical": "via_all_of"
+      },
+      "anonymous": false,
+      "docs": {},
+      "sensitive": false,
+      "provenance": {
+        "source": 0,
+        "pointer": "/components/schemas/ViaAllOf"
+      },
+      "base": {
+        "target": "t/openapi/components/schemas/Base",
+        "nullable": false
+      },
+      "constraints": {
+        "uniqueItems": false,
+        "minProps": 2
+      },
+      "abstract": false,
+      "positional": false,
+      "inputOnly": false
+    },
+    "t/openapi/components/schemas/ViaModel": {
+      "kind": "model",
+      "id": "t/openapi/components/schemas/ViaModel",
+      "name": {
+        "source": "ViaModel",
+        "canonical": "via_model"
+      },
+      "anonymous": false,
+      "docs": {},
+      "sensitive": false,
+      "provenance": {
+        "source": 0,
+        "pointer": "/components/schemas/ViaModel"
+      },
+      "properties": [
+        {
+          "id": "p/openapi/components/schemas/ViaModel/properties/a",
+          "name": {
+            "source": "a",
+            "canonical": "a"
+          },
+          "wireName": "a",
+          "type": {
+            "target": "t/prim/string",
+            "nullable": false
+          },
+          "required": false,
+          "clientOptional": false,
+          "defaultAdded": false,
+          "visibility": {
+            "none": false
+          },
+          "flatten": false,
+          "eventHeader": false,
+          "eventPayload": false,
+          "secret": false,
+          "docs": {},
+          "provenance": {
+            "source": 0,
+            "pointer": "/components/schemas/ViaModel/properties/a"
+          }
+        }
+      ],
+      "constraints": {
+        "uniqueItems": false,
+        "minProps": 2
+      },
+      "abstract": false,
+      "positional": false,
+      "inputOnly": false
+    },
+    "t/prim/string": {
+      "kind": "primitive",
+      "id": "t/prim/string",
+      "name": {},
+      "anonymous": false,
+      "docs": {},
+      "sensitive": false,
+      "provenance": {
+        "source": 0
+      },
+      "prim": "string"
+    }
+  },
+  "servers": [
+    {
+      "name": {
+        "hint": "server"
+      },
+      "urlTemplate": "/",
+      "description": {},
+      "auth": null
+    }
+  ],
+  "sources": [
+    {
+      "format": "openapi@3.1",
+      "path": "allof-position-constraints.yaml",
+      "hash": "8f0d33d038c59706de71c4c801a8989898caa9309509475fab447cdd84e79496"
+    }
+  ]
+}

testdata/conformance/openapi/allof-position-constraints.yaml

@@ -0,0 +1,8 @@
+openapi: 3.1.0
+info: {title: AllOfPositionConstraints, version: "1.0.0"}
+paths: {}
+components:
+  schemas:
+    Base:     {type: object, properties: {id: {type: string}}}
+    ViaModel: {type: object, properties: {a: {type: string}}, minProperties: 2}
+    ViaAllOf: {allOf: [{$ref: '#/components/schemas/Base'}], minProperties: 2}