fix(ts-input): Replace topLevelName for TypeScript input if first typ…

…e is export default (#2550)

packages/quicktype-typescript-input/src/index.ts

@@ -35,7 +35,24 @@ export function schemaForTypeScriptSources(sourceFileNames: string[]): JSONSchem
 
  const schema = generateSchema(program, "*", settings);
  const uris: string[] = [];
- let topLevelName: string | undefined = undefined;
+ let topLevelName: string = "";
+
+ // if there is a type that is `export default`, swap the corresponding ref
+ if (schema?.definitions?.default) {
+ const defaultDefinition = schema?.definitions?.default;
+ const matchingDefaultName = Object.entries(schema?.definitions ?? {}).find(
+ ([_name, definition]) => (definition as Record<string, unknown>)["$ref"] === "#/definitions/default"
+ )?.[0];
+
+ if (matchingDefaultName) {
+ topLevelName = matchingDefaultName;
+ (defaultDefinition as Record<string, unknown>).title = topLevelName;
+
+ schema.definitions[matchingDefaultName] = defaultDefinition;
+ schema.definitions.default = { $ref: `#/definitions/${matchingDefaultName}` };
+ }
+ }
+
  if (schema !== null && typeof schema === "object" && typeof schema.definitions === "object") {
  for (const name of Object.getOwnPropertyNames(schema.definitions)) {
  const definition = schema.definitions[name];
@@ -59,22 +76,18 @@ export function schemaForTypeScriptSources(sourceFileNames: string[]): JSONSchem
 
  uris.push(`#/definitions/${name}`);
 
- if (topLevelName === undefined) {
+ if (!topLevelName) {
  if (typeof definition.title === "string") {
  topLevelName = definition.title;
  } else {
  topLevelName = name;
  }
- } else {
- topLevelName = "";
  }
  }
  }
  if (uris.length === 0) {
  uris.push("#/definitions/");
  }
- if (topLevelName === undefined) {
- topLevelName = "";
- }
+
  return { schema: JSON.stringify(schema), name: topLevelName, uris, isConverted: true };
 }