fix: don't throw an error within a GaxiosError (#569)

src/common.ts

@@ -43,7 +43,14 @@ export class GaxiosError<T = any> extends Error {
     super(message);
 
     if (this.response) {
-      this.response.data = translateData(config.responseType, response?.data);
+      try {
+        this.response.data = translateData(config.responseType, response?.data);
+      } catch {
+        // best effort - don't throw an error within an error
+        // we could set `this.response.config.responseType = 'unknown'`, but
+        // that would mutate future calls with this config object.
+      }
+
       this.status = this.response.status;
     }
 
@@ -357,7 +364,7 @@ export function defaultErrorRedactor<T = any>(data: {
 
       data.config.url = url.toString();
     } catch {
-      // ignore error
+      // ignore error - no need to parse an invalid URL
     }
   }
 

test/test.getch.ts

@@ -98,6 +98,27 @@ describe('🚙 error handling', () => {
       }
     );
   });
+
+  it('should not throw an error during a translation error', () => {
+    const notJSON = '.';
+    const response: GaxiosResponse = {
+      config: {
+        responseType: 'json',
+      },
+      data: notJSON,
+      status: 500,
+      statusText: '',
+      headers: {},
+      request: {
+        responseURL: url,
+      },
+    };
+
+    const error = new GaxiosError('translation test', {}, response);
+
+    assert(error.response, undefined);
+    assert.equal(error.response.data, notJSON);
+  });
 });
 
 describe('🥁 configuration options', () => {