Register full schema of array items for known types

core/src/main/java/io/smallrye/openapi/runtime/scanner/dataobject/TypeProcessor.java

@@ -164,14 +164,17 @@ private Type readArrayType(ArrayType arrayType, Schema arraySchema) {
         // Only use component (excludes the special name formatting for arrays).
         TypeUtil.applyTypeAttributes(componentType, itemSchema);
 
-        // If it's not a terminal type, then push for later inspection.
         if (!isTerminalType(componentType) && index.containsClass(componentType)) {
+            // If it's not a terminal type, then push for later inspection.
             pushToStack(componentType, itemSchema);
+            itemSchema = context.getSchemaRegistry().registerReference(componentType, context.getJsonViews(), typeResolver,
+                    itemSchema);
+        } else {
+            // Otherwise, allow registration since we may not encounter the array's element type again.
+            itemSchema = context.getSchemaRegistry().checkRegistration(componentType, context.getJsonViews(), typeResolver,
+                    itemSchema);
         }
 
-        itemSchema = context.getSchemaRegistry().registerReference(componentType, context.getJsonViews(), typeResolver,
-                itemSchema);
-
         while (arrayType.dimensions() > 1) {
             Schema parentArrSchema = new SchemaImpl();
             parentArrSchema.setType(Schema.SchemaType.ARRAY);

core/src/test/java/io/smallrye/openapi/runtime/scanner/StandaloneSchemaScanTest.java

@@ -6,6 +6,7 @@
 import java.io.IOException;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Target;
+import java.time.ZonedDateTime;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -738,4 +739,27 @@ class Bean {
         printToConsole(result);
         assertJsonEquals("components.schemas.iterator-stream-map-types.json", result);
     }
+
+    /**
+     * Check that an array item that is considered "terminal" because it is a known type
+     * is registered in the schema registry and `#/components/schemas`.
+     *
+     * https://github.com/smallrye/smallrye-open-api/issues/1573
+     */
+    @Test
+    void testZonedDateTimeArrayWrapper() throws IOException, JSONException {
+        @Schema(name = "ZonedDateTimeArrayWrapper")
+        class ZonedDateTimeArrayWrapper {
+            @SuppressWarnings("unused")
+            ZonedDateTime[] now;
+        }
+
+        Index index = indexOf(ZonedDateTimeArrayWrapper.class, ZonedDateTime.class);
+        OpenApiAnnotationScanner scanner = new OpenApiAnnotationScanner(emptyConfig(), index);
+
+        OpenAPI result = scanner.scan();
+
+        printToConsole(result);
+        assertJsonEquals("components.schemas.terminal-array-item-registration.json", result);
+    }
 }

core/src/test/resources/io/smallrye/openapi/runtime/scanner/components.schemas.terminal-array-item-registration.json

@@ -0,0 +1,23 @@
+{
+  "openapi": "3.0.3",
+  "components": {
+    "schemas": {
+      "ZonedDateTimeArrayWrapper": {
+        "type": "object",
+        "properties": {
+          "now": {
+            "type": "array",
+            "items": {
+              "$ref": "#/components/schemas/ZonedDateTime"
+            }
+          }
+        }
+      },
+      "ZonedDateTime": {
+        "format": "date-time",
+        "type": "string",
+        "example": "2022-03-10T12:15:50-04:00"
+      }
+    }
+  }
+}