feat: implement 'nullable' and multiple types for union

lbguilherme · Dec 21, 2020 · 2085e84 · 2085e84
1 parent 2794b80
commit 2085e84
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Showing 2 changed files with 36 additions and 4 deletions.
diff --git a/index.d.ts b/index.d.ts
@@ -2,9 +2,10 @@ declare namespace AsTypedInternal {
   interface SchemaBase {
     $id?: string;
     $ref?: string;
-    type?: string;
+    type?: string | string[];
     title?: string;
     description?: string;
+    nullable?: boolean;
     default?: any;
     examples?: any[];
   }
@@ -211,9 +212,11 @@ declare namespace AsTypedInternal {
     | (ValueType extends StringSchema ? never : string)
     | (ValueType extends BoolSchema ? never : boolean);
 
-  type ResolveRecursiveInternal<
-    SchemaType
-  > = SchemaType extends SchemaDeclaration<null>
+  type ResolveRecursiveInternal<SchemaType> = SchemaType extends {
+    nullable: true;
+  }
+    ? ResolveRecursiveInternal<Omit<SchemaType, "nullable">> | null
+    : SchemaType extends SchemaDeclaration<null>
     ? null
     : SchemaType extends ConstSchema<infer Value>
     ? Value
@@ -237,6 +240,16 @@ declare namespace AsTypedInternal {
       >
     : SchemaType extends ArraySchema<infer ValueType>
     ? ResolveArray<ValueType>
+    : SchemaType extends {
+        type: [infer Type];
+      }
+    ? ResolveRecursiveInternal<Omit<SchemaType, "type"> & { type: Type }>
+    : SchemaType extends {
+        type: [infer Type, ...infer Rest];
+      }
+    ?
+        | ResolveRecursiveInternal<Omit<SchemaType, "type"> & { type: Type }>
+        | ResolveRecursiveInternal<Omit<SchemaType, "type"> & { type: Rest }>
     : never;
 
   // TODO

diff --git a/test.ts b/test.ts
@@ -11,6 +11,12 @@ assert(_ as AsTyped<{ type: "integer" }>, _ as number);
 
 assert(_ as AsTyped<{ type: "string" }>, _ as string);
 
+assert(_ as AsTyped<{ type: ["string", "null"] }>, _ as string | null);
+
+assert(_ as AsTyped<{ type: "string"; nullable: true }>, _ as string | null);
+
+assert(_ as AsTyped<{ type: "string"; nullable: false }>, _ as string);
+
 assert(_ as AsTyped<{ type: "boolean" }>, _ as boolean);
 
 assert(_ as AsTyped<{ type: "null" }>, _ as null);
@@ -182,6 +188,19 @@ assert(
   _ as { arr?: Array<{ [name: string]: string }> }
 );
 
+assert(
+  _ as AsTyped<{
+    type: ["object", "boolean", "null"];
+    properties: {
+      arr: {
+        type: "array";
+        items: { type: "object"; additionalProperties: { type: "string" } };
+      };
+    };
+  }>,
+  _ as { arr?: Array<{ [name: string]: string }> } | boolean | null
+);
+
 /*
  * assert(
  *   _ as AsTyped<{