This is a testharness.js-based test.
[FAIL] ReadableStream start() Error propagates to Response.arrayBuffer() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Start error"
[FAIL] ReadableStream start() Error propagates to Response.blob() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Start error"
[FAIL] ReadableStream start() Error propagates to Response.bytes() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Start error"
[FAIL] ReadableStream start() Error propagates to Response.formData() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Start error"
[FAIL] ReadableStream start() Error propagates to Response.json() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Start error"
[FAIL] ReadableStream start() Error propagates to Response.text() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Start error"
[FAIL] ReadableStream pull() Error propagates to Response.arrayBuffer() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Pull error"
[FAIL] ReadableStream pull() Error propagates to Response.blob() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Pull error"
[FAIL] ReadableStream pull() Error propagates to Response.bytes() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Pull error"
[FAIL] ReadableStream pull() Error propagates to Response.formData() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Pull error"
[FAIL] ReadableStream pull() Error propagates to Response.json() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Pull error"
[FAIL] ReadableStream pull() Error propagates to Response.text() Promise
  promise_rejects_exactly: CustomTestError should propagate function "function() { throw e; }" threw object "TypeError: Failed to fetch" but we expected it to throw object "Error: Pull error"
Harness: the test ran to completion.