fix: only fallback to text on error (#14)

package.json

@@ -15,8 +15,8 @@
   "module": "./lib/index.js",
   "exports": {
     "types": "./lib/index.d.ts",
-    "import": "./lib/index.js",
-    "require": "./lib/index.cjs"
+    "require": "./lib/index.cjs",
+    "default": "./lib/index.js"
   },
   "types": "./lib/index.d.ts",
   "files": [

src/index.ts

@@ -97,7 +97,7 @@ export const createFetchApi = (fetch = globalThis.fetch) => {
         return response
       }
       throw Object.assign(new Error(response.statusText), {
-        data: extractDataFromResponse(response, type),
+        data: extractDataFromResponse(response, type, true),
         response,
       })
     }

src/utils.ts

@@ -60,31 +60,38 @@ export const normalizeUrl = (url: string, query?: URLSearchParamsOptions) => {
 export async function extractDataFromResponse(
   res: Response,
   type: null,
+  fallback?: boolean,
 ): Promise<Response>
 export async function extractDataFromResponse(
   res: Response,
   type: 'arrayBuffer',
+  fallback?: boolean,
 ): Promise<ArrayBuffer>
 export async function extractDataFromResponse(
   res: Response,
   type: 'blob',
+  fallback?: boolean,
 ): Promise<Blob>
 export async function extractDataFromResponse<T>(
   res: Response,
   type: 'json',
+  fallback?: boolean,
 ): Promise<T>
 export async function extractDataFromResponse(
   res: Response,
   type: 'text',
+  fallback?: boolean,
 ): Promise<string>
 export async function extractDataFromResponse(
   res: Response,
   type: ResponseType,
+  fallback?: boolean,
 ): Promise<unknown>
 // eslint-disable-next-line sonarjs/cognitive-complexity
 export async function extractDataFromResponse(
   res: Response,
   type: ResponseType,
+  fallback?: boolean,
 ) {
   let data: unknown
   if (type != null) {
@@ -93,15 +100,26 @@ export async function extractDataFromResponse(
         // data could be empty text
         data = await res.clone().text()
       } catch {}
-      if (type === 'json' && (data = (data as string).trim())) {
-        try {
-          data = JSON.parse(data as string)
-        } catch {}
+      if (type === 'json') {
+        if ((data = (data as string).trim())) {
+          try {
+            data = JSON.parse(data as string)
+          } catch (err) {
+            if (!fallback) {
+              throw err
+            }
+          }
+        } else {
+          data = null
+        }
       }
     } else {
       try {
         data = await res.clone()[type]()
-      } catch {
+      } catch (err) {
+        if (!fallback) {
+          throw err
+        }
         data = await res.clone().text()
       }
     }

test/utils.spec.ts

@@ -43,7 +43,15 @@ test('extractDataFromResponse', async () => {
   expect(await extractDataFromResponse(new Response(), 'text')).toBe('')
   expect(await extractDataFromResponse(new Response(null), 'text')).toBe('')
   expect(await extractDataFromResponse(new Response('foo'), 'text')).toBe('foo')
-  expect(await extractDataFromResponse(new Response('foo'), 'json')).toBe('foo')
+  await expect(() =>
+    extractDataFromResponse(new Response('foo'), 'json'),
+  ).rejects.toThrow(
+    // eslint-disable-next-line unicorn/better-regex, regexp/no-dupe-characters-character-class
+    /[SyntaxError: Unexpected token (('o', "foo" is not valid JSON)|(o in JSON at position 1))]/,
+  )
+  expect(await extractDataFromResponse(new Response('foo'), 'json', true)).toBe(
+    'foo',
+  )
   expect(
     await extractDataFromResponse(new Response('{"foo":"bar"}'), 'json'),
   ).toEqual({ foo: 'bar' })