Diff is empty when lines are too long
Author: taiyangcCreated Mar 27, 2019Updated Jul 17, 2026
Labelshelp wanted
On assert.Equal failures, if the diff has long lines (due to complicated structs), instead of showing something like
require.go:157:
Error Trace: common_test.go:72
transactions_test.go:844
Error: Not equal:
expected: ...
actual: ...
Diff:
--- Expected
+++ Actual
<super long line...>
Test: TestTransactionsQueryFingerprint
Messages: Response does not match expected returnCurrently the diff is completely cut off
require.go:157:
Error Trace: common_test.go:72
transactions_test.go:844
Error: Not equal:
Test: TestTransactionsQueryFingerprint
Messages: Response does not match expected returnThis makes testing hard to check which lines differed.
Upon inspecting, indentation formatting of diff lines is using bufio.Scanner which has a default MaxScanTokenSize (64K) and would not parse long lines: https://github.com/stretchr/testify/blob/master/assert/assertions.go#L201
Can be fixed by either changing from bufio.Scanner to bufio.Reader or truncating long lines up to the max token size (or even provide a config to change max). Thoughts?
Source: stretchr/testify