Improve support for generating aggregated inlined objects (#264)

Fabrikt now supports inlined definitions of aggregated objects > 1. For example:
```
    Dog:
      type: object
      properties:
        walker:
          allOf:
            - $ref: "#/components/schemas/Person"
            - $ref: "#/components/schemas/Company"

```
Support is preserved for the special case where the aggregation is over a single schema.
Highlighted by the API supplied in Issue #262

src/main/kotlin/com/cjbooms/fabrikt/util/KaizenParserExtensions.kt

@@ -39,11 +39,14 @@ object KaizenParserExtensions {
         getDiscriminatorForInLinedObjectUnderAllOf()?.propertyName != null
 
     fun Schema.isInlinedObjectDefinition() =
-        isObjectType() && !isSchemaLess() && (
+        (isObjectType() || isAggregatedObject()) && !isSchemaLess() && (
             Overlay.of(this).pathFromRoot.contains("properties") ||
                 Overlay.of(this).pathFromRoot.contains("items")
             )
 
+    private fun Schema.isAggregatedObject(): Boolean =
+        combinedAnyOfAndAllOfSchemas().size > 1
+
     fun Schema.isInlinedTypedAdditionalProperties() =
         isObjectType() && !isSchemaLess() && Overlay.of(this).pathFromRoot.contains("additionalProperties")
 
@@ -188,7 +191,7 @@ object KaizenParserExtensions {
     fun Schema.safeName(): String =
         when {
             isOneOfPolymorphicTypes() -> this.oneOfSchemas.first().allOfSchemas.first().safeName()
-            isPropertyWithAllOfSingleType() -> this.allOfSchemas.first().safeName()
+            isInlinedAggregationOfExactlyOne() -> combinedAnyOfAndAllOfSchemas().first().safeName()
             name != null -> name
             else -> Overlay.of(this).pathFromRoot
                 .splitToSequence("/")
@@ -222,8 +225,11 @@ object KaizenParserExtensions {
     fun Schema.isOneOfSuperInterface() =
         discriminator != null && discriminator.propertyName != null && oneOfSchemas.isNotEmpty()
 
-    private fun Schema.isPropertyWithAllOfSingleType() =
-        allOfSchemas?.size == 1 && isInlinedPropertySchema()
+    private fun Schema.isInlinedAggregationOfExactlyOne() =
+        combinedAnyOfAndAllOfSchemas().size == 1 && isInlinedPropertySchema()
+
+    private fun Schema.combinedAnyOfAndAllOfSchemas(): List<Schema> =
+        (allOfSchemas ?: emptyList()) + (anyOfSchemas ?: emptyList())
 
     /**
      * The `pathFromRoot` of a property schema ends with

src/test/kotlin/com/cjbooms/fabrikt/generators/ModelGeneratorTest.kt

@@ -49,7 +49,7 @@ class ModelGeneratorTest {
         "validationAnnotations",
         "wildCardTypes",
         "singleAllOf",
-        "singleAllOfProperty",
+        "inlinedAggregatedObjects",
         "responsesSchema",
         "webhook",
         "instantDateTime",

src/test/resources/examples/singleAllOfProperty/api.yaml → src/test/resources/examples/inlinedAggregatedObjects/api.yaml

@@ -19,6 +19,7 @@ components:
           description: "The person walking the dog."
           allOf:
             - $ref: "#/components/schemas/Person"
+            - $ref: "#/components/schemas/Company"
 
     Person:
       type: object
@@ -27,3 +28,11 @@ components:
       properties:
         name:
           type: string
+
+    Company:
+      type: object
+      required:
+        - companyName
+      properties:
+        companyName:
+          type: string

src/test/resources/examples/inlinedAggregatedObjects/models/Models.kt

@@ -0,0 +1,42 @@
+package examples.inlinedAggregatedObjects.models
+
+import com.fasterxml.jackson.`annotation`.JsonProperty
+import javax.validation.Valid
+import javax.validation.constraints.NotNull
+import kotlin.String
+
+public data class Company(
+    @param:JsonProperty("companyName")
+    @get:JsonProperty("companyName")
+    @get:NotNull
+    public val companyName: String,
+)
+
+public data class Dog(
+    @param:JsonProperty("owner")
+    @get:JsonProperty("owner")
+    @get:Valid
+    public val owner: Person? = null,
+    @param:JsonProperty("walker")
+    @get:JsonProperty("walker")
+    @get:Valid
+    public val walker: DogWalker? = null,
+)
+
+public data class DogWalker(
+    @param:JsonProperty("name")
+    @get:JsonProperty("name")
+    @get:NotNull
+    public val name: String,
+    @param:JsonProperty("companyName")
+    @get:JsonProperty("companyName")
+    @get:NotNull
+    public val companyName: String,
+)
+
+public data class Person(
+    @param:JsonProperty("name")
+    @get:JsonProperty("name")
+    @get:NotNull
+    public val name: String,
+)