diff --git a/CHANGELOG.adoc b/CHANGELOG.adoc
index 443bf7b1..4cf7a831 100644
--- a/CHANGELOG.adoc
+++ b/CHANGELOG.adoc
@@ -13,6 +13,9 @@
== Unreleased changes (barbacane-dev fork)
+=== Tests / docs
+* tighten the multi-type `type` + subschemas regression fixture and code comment, per upstream review feedback on https://github.com/oxidecomputer/typify/pull/1001[oxidecomputer/typify#1001]: drop the `SingleTypeOneOfArrayBranch` case (whose contradictory schema caused codegen to emit an unreachable enum variant), trim verbose `$comment` rationales, and shorten the match-arm doc comment in `convert.rs`
+
https://github.com/barbacane-dev/typify/compare/v1.0.0\...HEAD[Full list of commits]
== 1.0.0 (released 2026-05-13)
diff --git a/typify-impl/src/convert.rs b/typify-impl/src/convert.rs
index ebd2ecc2..50a9a82f 100644
--- a/typify-impl/src/convert.rs
+++ b/typify-impl/src/convert.rs
@@ -464,12 +464,9 @@ impl TypeSpace {
extensions: _,
} => self.convert_unknown_enum(type_name, original_schema, metadata, enum_values),
- // Subschemas with no body validation and either no type or a
+ // Subschemas with no additional validation and either no type or a
// single type. A multi-type (`Vec`) instance_type is deliberately
- // excluded so that it flows through the merge arm below, which
- // folds the type union into each subschema branch. Preserving the
- // earlier behaviour for `None` / `Single` keeps existing tolerant
- // handling of schemas whose outer type may conflict with a branch.
+ // excluded so that it flows through the merge arm below.
SchemaObject {
metadata,
instance_type: None | Some(SingleOrVec::Single(_)),
diff --git a/typify/tests/schemas/type-array-with-subschemas.json b/typify/tests/schemas/type-array-with-subschemas.json
index 18f26a45..686c4876 100644
--- a/typify/tests/schemas/type-array-with-subschemas.json
+++ b/typify/tests/schemas/type-array-with-subschemas.json
@@ -1,9 +1,8 @@
{
"$schema": "http://json-schema.org/draft-07/schema#",
- "$comment": "Regression coverage for issue #954: schemas with a multi-type `type: [...]` array on the same object as `oneOf` / `anyOf` / `allOf` / `not` previously discarded the `type` constraint (TODO at convert.rs wildcarded `instance_type`). Single-type + subschema cases must still pass through the earlier arm unchanged.",
+ "$comment": "Coverage for issue #954: multi-type `type: [...]` alongside oneOf/anyOf/allOf/not.",
"definitions": {
"TypeArrayOneOfItems": {
- "$comment": "Canonical issue #954 shape. Each oneOf branch only constrains `items`, so the type union must be folded into every branch rather than dropped.",
"type": [ "string", "number", "boolean", "array" ],
"oneOf": [
{ "items": { "type": "string" } },
@@ -12,7 +11,6 @@
]
},
"TypeArrayAnyOfItems": {
- "$comment": "Same shape as TypeArrayOneOfItems but using anyOf. anyOf travels through try_merge_with_each_subschema on a sibling path from oneOf; it should fold the type union the same way.",
"type": [ "string", "number", "array" ],
"anyOf": [
{ "items": { "type": "string" } },
@@ -20,7 +18,6 @@
]
},
"TypeArrayAllOfRefinement": {
- "$comment": "allOf is folded pairwise into the parent rather than producing branches. The type union must survive and the array-only constraints should apply when the Array variant is selected.",
"type": [ "string", "array" ],
"allOf": [
{ "items": { "type": "string" } },
@@ -28,29 +25,11 @@
]
},
"TypeArrayNotExclusion": {
- "$comment": "not: object is redundant when the outer type union excludes object, but merging must not drop the type union when the not branch is applied.",
"type": [ "string", "number", "array" ],
"not": { "type": "object" }
},
- "SingleTypeOneOfArrayBranch": {
- "$comment": "Regression guard (rust-collisions pattern). Outer singleton type + oneOf where one branch has a conflicting explicit type. This must continue to pass through the earlier arm (no merge), otherwise the array branch becomes unsatisfiable and is silently dropped.",
- "type": "object",
- "oneOf": [
- {
- "type": "object",
- "properties": { "kind": { "type": "string" } },
- "required": [ "kind" ]
- },
- {
- "type": "array",
- "items": { "type": "string" },
- "minItems": 2,
- "maxItems": 2
- }
- ]
- },
"TypeArrayOneOfExplicitArrayBranches": {
- "$comment": "Case 7: each oneOf branch pins `type: array`, so the intersection with the outer type union must prune the non-array primitives. Only array variants should be emitted.",
+ "$comment": "Each oneOf branch pins `type: array`; the non-array variants from the outer union should be pruned.",
"type": [ "string", "array" ],
"oneOf": [
{ "type": "array", "items": { "type": "string" } },
@@ -58,7 +37,7 @@
]
},
"TypeArrayPartiallyUnsatisfiableOneOf": {
- "$comment": "Some oneOf branches conflict with the outer type union and should be dropped during merge; the surviving branch must carry the outer type union. The two eliminated branches use object/number which the outer `[string, array]` disallows.",
+ "$comment": "Two oneOf branches conflict with the outer type union and should be dropped during merge.",
"type": [ "string", "array" ],
"oneOf": [
{ "type": "object", "properties": { "name": { "type": "string" } } },
@@ -67,7 +46,7 @@
]
},
"TypeArrayFullyUnsatisfiableOneOf": {
- "$comment": "Case 9: every branch conflicts with the outer type union, so `try_merge_with_each_subschema` returns empty and the schema resolves to never. Must emit an empty enum cleanly rather than panic.",
+ "$comment": "Every branch conflicts with the outer type union; must resolve cleanly rather than panic.",
"type": [ "string", "number" ],
"oneOf": [
{ "type": "array", "items": { "type": "string" } },
@@ -75,7 +54,7 @@
]
},
"TypeArrayOneOfAndAllOf": {
- "$comment": "Case 10: oneOf and allOf on the same object, both alongside a multi-type `type` array. Exercises the full merge path (allOf folded first, then oneOf fanned out) with the Vec instance_type flowing through the merge arm.",
+ "$comment": "oneOf and allOf on the same object, plus a multi-type `type` array.",
"type": [ "string", "array" ],
"allOf": [
{ "minLength": 1 }
diff --git a/typify/tests/schemas/type-array-with-subschemas.rs b/typify/tests/schemas/type-array-with-subschemas.rs
index abd17f6b..14725ea4 100644
--- a/typify/tests/schemas/type-array-with-subschemas.rs
+++ b/typify/tests/schemas/type-array-with-subschemas.rs
@@ -25,56 +25,12 @@ pub mod error {
}
}
}
-#[doc = "`SingleTypeOneOfArrayBranch`"]
-#[doc = r""]
-#[doc = r" JSON schema
"]
-#[doc = r""]
-#[doc = r" ```json"]
-#[doc = "{"]
-#[doc = " \"$comment\": \"Regression guard (rust-collisions pattern). Outer singleton type + oneOf where one branch has a conflicting explicit type. This must continue to pass through the earlier arm (no merge), otherwise the array branch becomes unsatisfiable and is silently dropped.\","]
-#[doc = " \"oneOf\": ["]
-#[doc = " {"]
-#[doc = " \"properties\": {"]
-#[doc = " \"kind\": {"]
-#[doc = " \"type\": \"string\""]
-#[doc = " }"]
-#[doc = " },"]
-#[doc = " \"required\": ["]
-#[doc = " \"kind\""]
-#[doc = " ],"]
-#[doc = " \"type\": \"object\""]
-#[doc = " },"]
-#[doc = " {"]
-#[doc = " \"items\": {"]
-#[doc = " \"type\": \"string\""]
-#[doc = " },"]
-#[doc = " \"maxItems\": 2,"]
-#[doc = " \"minItems\": 2,"]
-#[doc = " \"type\": \"array\""]
-#[doc = " }"]
-#[doc = " ],"]
-#[doc = " \"type\": \"object\""]
-#[doc = "}"]
-#[doc = r" ```"]
-#[doc = r" JSON schema
"]
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"allOf is folded pairwise into the parent rather than producing branches. The type union must survive and the array-only constraints should apply when the Array variant is selected.\","]
#[doc = " \"allOf\": ["]
#[doc = " {"]
#[doc = " \"items\": {"]
@@ -109,7 +65,6 @@ impl ::std::convert::From<::std::vec::Vec<::std::string::String>> for TypeArrayA
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"Same shape as TypeArrayOneOfItems but using anyOf. anyOf travels through try_merge_with_each_subschema on a sibling path from oneOf; it should fold the type union the same way.\","]
#[doc = " \"anyOf\": ["]
#[doc = " {"]
#[doc = " \"items\": {"]
@@ -154,7 +109,6 @@ impl ::std::convert::From for TypeArrayAnyOfItems {
#[doc = "{"]
#[doc = " \"allOf\": ["]
#[doc = " {"]
-#[doc = " \"$comment\": \"Same shape as TypeArrayOneOfItems but using anyOf. anyOf travels through try_merge_with_each_subschema on a sibling path from oneOf; it should fold the type union the same way.\","]
#[doc = " \"type\": ["]
#[doc = " \"string\","]
#[doc = " \"number\","]
@@ -202,7 +156,6 @@ impl ::std::convert::From<::std::vec::Vec<::std::string::String>> for TypeArrayA
#[doc = "{"]
#[doc = " \"allOf\": ["]
#[doc = " {"]
-#[doc = " \"$comment\": \"Same shape as TypeArrayOneOfItems but using anyOf. anyOf travels through try_merge_with_each_subschema on a sibling path from oneOf; it should fold the type union the same way.\","]
#[doc = " \"type\": ["]
#[doc = " \"string\","]
#[doc = " \"number\","]
@@ -248,7 +201,7 @@ impl ::std::convert::From<::std::vec::Vec> for TypeArrayAnyOfItemsVariant1
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"Case 9: every branch conflicts with the outer type union, so `try_merge_with_each_subschema` returns empty and the schema resolves to never. Must emit an empty enum cleanly rather than panic.\","]
+#[doc = " \"$comment\": \"Every branch conflicts with the outer type union; must resolve cleanly rather than panic.\","]
#[doc = " \"oneOf\": ["]
#[doc = " {"]
#[doc = " \"items\": {"]
@@ -292,7 +245,6 @@ pub enum TypeArrayFullyUnsatisfiableOneOf {}
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"not: object is redundant when the outer type union excludes object, but merging must not drop the type union when the not branch is applied.\","]
#[doc = " \"not\": {"]
#[doc = " \"type\": \"object\""]
#[doc = " },"]
@@ -327,7 +279,7 @@ impl ::std::convert::From<::std::vec::Vec<::serde_json::Value>> for TypeArrayNot
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"Case 10: oneOf and allOf on the same object, both alongside a multi-type `type` array. Exercises the full merge path (allOf folded first, then oneOf fanned out) with the Vec instance_type flowing through the merge arm.\","]
+#[doc = " \"$comment\": \"oneOf and allOf on the same object, plus a multi-type `type` array.\","]
#[doc = " \"allOf\": ["]
#[doc = " {"]
#[doc = " \"minLength\": 1"]
@@ -604,7 +556,7 @@ impl<'de> ::serde::Deserialize<'de> for TypeArrayOneOfAndAllOfVariant1String {
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"Case 7: each oneOf branch pins `type: array`, so the intersection with the outer type union must prune the non-array primitives. Only array variants should be emitted.\","]
+#[doc = " \"$comment\": \"Each oneOf branch pins `type: array`; the non-array variants from the outer union should be pruned.\","]
#[doc = " \"oneOf\": ["]
#[doc = " {"]
#[doc = " \"items\": {"]
@@ -650,7 +602,6 @@ impl ::std::convert::From<::std::vec::Vec> for TypeArrayOneOfExplicitArrayB
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"Canonical issue #954 shape. Each oneOf branch only constrains `items`, so the type union must be folded into every branch rather than dropped.\","]
#[doc = " \"oneOf\": ["]
#[doc = " {"]
#[doc = " \"items\": {"]
@@ -707,7 +658,6 @@ impl ::std::convert::From for TypeArrayOneOfItems {
#[doc = "{"]
#[doc = " \"allOf\": ["]
#[doc = " {"]
-#[doc = " \"$comment\": \"Canonical issue #954 shape. Each oneOf branch only constrains `items`, so the type union must be folded into every branch rather than dropped.\","]
#[doc = " \"type\": ["]
#[doc = " \"string\","]
#[doc = " \"number\","]
@@ -769,7 +719,6 @@ impl ::std::convert::From<::std::vec::Vec<::std::string::String>> for TypeArrayO
#[doc = "{"]
#[doc = " \"allOf\": ["]
#[doc = " {"]
-#[doc = " \"$comment\": \"Canonical issue #954 shape. Each oneOf branch only constrains `items`, so the type union must be folded into every branch rather than dropped.\","]
#[doc = " \"type\": ["]
#[doc = " \"string\","]
#[doc = " \"number\","]
@@ -831,7 +780,6 @@ impl ::std::convert::From<::std::vec::Vec> for TypeArrayOneOfItemsVariant1
#[doc = "{"]
#[doc = " \"allOf\": ["]
#[doc = " {"]
-#[doc = " \"$comment\": \"Canonical issue #954 shape. Each oneOf branch only constrains `items`, so the type union must be folded into every branch rather than dropped.\","]
#[doc = " \"type\": ["]
#[doc = " \"string\","]
#[doc = " \"number\","]
@@ -891,7 +839,7 @@ impl ::std::convert::From<::std::vec::Vec> for TypeArrayOneOfItemsVariant2
#[doc = r""]
#[doc = r" ```json"]
#[doc = "{"]
-#[doc = " \"$comment\": \"Some oneOf branches conflict with the outer type union and should be dropped during merge; the surviving branch must carry the outer type union. The two eliminated branches use object/number which the outer `[string, array]` disallows.\","]
+#[doc = " \"$comment\": \"Two oneOf branches conflict with the outer type union and should be dropped during merge.\","]
#[doc = " \"oneOf\": ["]
#[doc = " {"]
#[doc = " \"properties\": {"]