feat: Support nullable on allOf schemas (#229)

Author: Cellule

plugins/typescript/src/core/schemaToTypeAliasDeclaration.test.ts

@@ -65,7 +65,7 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema)).toBe(
-      `export type Test = "foo" | "bar" | "baz";`,
+      `export type Test = "foo" | "bar" | "baz";`
     );
   });
 
@@ -129,7 +129,7 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema)).toBe(
-      `export type Test = "foo" | "bar" | "baz" | null;`,
+      `export type Test = "foo" | "bar" | "baz" | null;`
     );
   });
 
@@ -423,7 +423,7 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema)).toMatchInlineSnapshot(
-      `"export type Test = User;"`,
+      `"export type Test = User;"`
     );
   });
 
@@ -433,7 +433,7 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema, "Test", "parameters")).toMatchInlineSnapshot(
-      `"export type Test = Schemas.User;"`,
+      `"export type Test = Schemas.User;"`
     );
   });
 
@@ -443,7 +443,7 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema)).toMatchInlineSnapshot(
-      `"export type Test = Record<string, any>;"`,
+      `"export type Test = Record<string, any>;"`
     );
   });
 
@@ -566,15 +566,15 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema)).toMatchInlineSnapshot(
-      `"export type Test = Foo[];"`,
+      `"export type Test = Foo[];"`
     );
   });
 
   it("should generate void", () => {
     const schema: SchemaObject = {};
 
     expect(printSchema(schema)).toMatchInlineSnapshot(
-      `"export type Test = void;"`,
+      `"export type Test = void;"`
     );
   });
 
@@ -584,7 +584,7 @@ describe("schemaToTypeAliasDeclaration", () => {
     };
 
     expect(printSchema(schema)).toMatchInlineSnapshot(
-      `"export type Test = string | number;"`,
+      `"export type Test = string | number;"`
     );
   });
 
@@ -633,7 +633,7 @@ describe("schemaToTypeAliasDeclaration", () => {
               },
             },
           },
-        }),
+        })
       ).toMatchInlineSnapshot(`
        "export type Test = (Omit<Foo, "discriminatorPropertyName"> & {
            discriminatorPropertyName: "foo";
@@ -653,7 +653,7 @@ describe("schemaToTypeAliasDeclaration", () => {
             Bar: { type: "object", properties: { bar: { type: "string" } } },
             Baz: { type: "object", properties: { baz: { type: "string" } } },
           },
-        }),
+        })
       ).toMatchInlineSnapshot(`
        "export type Test = (Foo & {
            discriminatorPropertyName: "foo";
@@ -699,7 +699,7 @@ describe("schemaToTypeAliasDeclaration", () => {
               required: ["discriminatorPropertyName"],
             },
           },
-        }),
+        })
       ).toMatchInlineSnapshot(`"export type Test = Foo | Bar | Baz;"`);
     });
   });
@@ -773,6 +773,23 @@ describe("schemaToTypeAliasDeclaration", () => {
           `);
     });
 
+    it("should combine nullable & allOf", () => {
+      const schema: SchemaObject = {
+        allOf: [
+          { type: "object", properties: { foo: { type: "string" } } },
+          { type: "object", properties: { bar: { type: "number" } } },
+        ],
+        nullable: true,
+      };
+
+      expect(printSchema(schema)).toMatchInlineSnapshot(`
+      "export type Test = {
+          foo?: string;
+          bar?: number;
+      } | null;"
+    `);
+    });
+
     it("should combine inline types", () => {
       const schema: SchemaObject = {
         allOf: [
@@ -846,7 +863,7 @@ describe("schemaToTypeAliasDeclaration", () => {
       };
 
       expect(printSchema(schema)).toMatchInlineSnapshot(
-        `"export type Test = never;"`,
+        `"export type Test = never;"`
       );
     });
 
@@ -920,7 +937,7 @@ describe("schemaToTypeAliasDeclaration", () => {
       };
 
       expect(printSchema(schema)).toMatchInlineSnapshot(
-        `"export type Test = string | number;"`,
+        `"export type Test = string | number;"`
       );
     });
 
@@ -1061,7 +1078,7 @@ const printSchema = (
   schemaName: string = "Test",
   currentComponent: OpenAPIComponentType = "schemas",
   components?: OpenAPIObject["components"],
-  useEnums?: boolean,
+  useEnums?: boolean
 ) => {
   const nodes = schemaToTypeAliasDeclaration(
     schemaName,
@@ -1070,13 +1087,13 @@ const printSchema = (
       currentComponent,
       openAPIDocument: { components },
     },
-    useEnums,
+    useEnums
   );
 
   const sourceFile = ts.createSourceFile(
     "index.ts",
     "",
-    ts.ScriptTarget.Latest,
+    ts.ScriptTarget.Latest
   );
 
   const printer = ts.createPrinter({
@@ -1086,7 +1103,7 @@ const printSchema = (
 
   return nodes
     .map((node: ts.Node) =>
-      printer.printNode(ts.EmitHint.Unspecified, node, sourceFile),
+      printer.printNode(ts.EmitHint.Unspecified, node, sourceFile)
     )
     .join("\n");
 };

plugins/typescript/src/core/schemaToTypeAliasDeclaration.ts

@@ -142,6 +142,14 @@ export const getType = (
         additionalProperties: schema.additionalProperties,
       });
     }
+
+    if (schema.nullable) {
+      return f.createUnionTypeNode([
+        getAllOf([...schema.allOf, ...adHocSchemas], context),
+        f.createLiteralTypeNode(f.createNull()),
+      ]);
+    }
+
     return getAllOf([...schema.allOf, ...adHocSchemas], context);
   }