From fd909cfe23dd2d61b7c43369d0a8578d2aed71e3 Mon Sep 17 00:00:00 2001 From: Katie Hockman Date: Thu, 16 Sep 2021 10:03:04 -0400 Subject: [PATCH] [dev.fuzz] Revert "[dev.fuzz] testing: convert seed corpus values where possible" This reverts commit 413c125da38990720744c0d98ab65c0d5b1602da. Reason for revert: Giving this more thought, we've decided that converting types under the hood may cause unexpected behavior to users. This is a feature that can always be added after more consideration has been done, but is not something that can be removed due to the backwards compatibility promise. Updates golang/go#45593 Change-Id: I79bab24979d7e4c294e6cb6455d4c7729d6a0efb Reviewed-on: https://go-review.googlesource.com/c/go/+/350251 Trust: Katie Hockman Trust: Joe Tsai Run-TryBot: Katie Hockman TryBot-Result: Go Bot Reviewed-by: Jay Conrod Reviewed-by: Joe Tsai --- fuzz/fuzz.go | 36 ++++-------------------------------- 1 file changed, 4 insertions(+), 32 deletions(-) diff --git a/fuzz/fuzz.go b/fuzz/fuzz.go index 99cf39e..2cd7ebb 100644 --- a/fuzz/fuzz.go +++ b/fuzz/fuzz.go @@ -942,47 +942,19 @@ func readCorpusData(data []byte, types []reflect.Type) ([]interface{}, error) { } // CheckCorpus verifies that the types in vals match the expected types -// provided. If not, attempt to convert them. If that's not possible, return an -// error. +// provided. func CheckCorpus(vals []interface{}, types []reflect.Type) error { if len(vals) != len(types) { - return fmt.Errorf("wrong number of values in corpus file: %d, want %d", len(vals), len(types)) + return fmt.Errorf("wrong number of values in corpus entry: %d, want %d", len(vals), len(types)) } for i := range types { - orig := reflect.ValueOf(vals[i]) - origType := orig.Type() - wantType := types[i] - if origType == wantType { - continue // already the same type + if reflect.TypeOf(vals[i]) != types[i] { + return fmt.Errorf("mismatched types in corpus entry: %v, want %v", vals, types) } - // Attempt to convert the corpus value to the expected type - if !origType.ConvertibleTo(wantType) { - return fmt.Errorf("cannot convert %v to %v", origType, wantType) - } - convertedVal, ok := convertToType(orig, wantType) - if !ok { - return fmt.Errorf("error converting %v to %v", origType, wantType) - } - // TODO: Check that the value didn't change. - // e.g. val went from int64(-1) -> uint(0) -> int64(0) which should fail - - // Updates vals to use the newly converted value of the expected type. - vals[i] = convertedVal.Interface() } return nil } -func convertToType(orig reflect.Value, t reflect.Type) (converted reflect.Value, ok bool) { - // Convert might panic even if ConvertibleTo returns true, so catch - // that panic and return false. - defer func() { - if r := recover(); r != nil { - ok = false - } - }() - return orig.Convert(t), true -} - // writeToCorpus atomically writes the given bytes to a new file in testdata. // If the directory does not exist, it will create one. If the file already // exists, writeToCorpus will not rewrite it. writeToCorpus returns the