fix(walker): anyOf/oneOf handling

Author: P0lip

src/tree/tree.ts

@@ -6,8 +6,8 @@ import type { SchemaTreeRefDereferenceFn } from '../resolver/types';
 import type { SchemaFragment } from '../types';
 import { isObjectLiteral } from '../utils';
 import { get } from '../utils/get';
+import { Walker } from '../walker';
 import type { WalkerRefResolver } from '../walker/types';
-import { Walker } from '../walker/walk';
 
 export type SchemaTreeOptions = {
   mergeAllOf: boolean;
@@ -26,6 +26,10 @@ export class SchemaTree {
     });
   }
 
+  public clear() {
+    this.root.children.length = 0;
+  }
+
   public populate() {
     this.invokeWalker(this.walker);
   }

src/walker/index.ts

@@ -0,0 +1,2 @@
+export * from './walker';
+export * from './types';

src/walker/walk.ts renamed to src/walker/walker.ts

@@ -240,8 +240,14 @@ export class Walker extends EventEmitter<Dictionary<WalkerEventHandler, WalkerEv
 
     if (SchemaCombinerName.OneOf in fragment || SchemaCombinerName.AnyOf in fragment) {
       try {
-        for (const item of mergeOneOrAnyOf(fragment, path, walkingOptions)) {
-          yield new RegularNode(item);
+        const merged = mergeOneOrAnyOf(fragment, path, walkingOptions);
+        if (merged.length === 1) {
+          yield new RegularNode(merged[0]);
+        } else {
+          const combiner = SchemaCombinerName.OneOf in fragment ? SchemaCombinerName.OneOf : SchemaCombinerName.AnyOf;
+          yield new RegularNode({
+            [combiner]: merged,
+          });
         }
 
         return;