Upstream gookit/goutil state of the touched files before 949a07a2cc

PR.md

@@ -1,74 +0,0 @@
-# fix(strutil): BaseConv family returns "0" for zero instead of empty string
-
-## Problem
-
-Converting the value zero through the base-conversion helpers returns an empty
-string instead of `"0"`:
-
-```go
-strutil.BaseConv("0", 10, 16)   // "" , want "0"
-strutil.BaseConv("0", 16, 10)   // "" , want "0"
-strutil.Base10Conv("0", 62)     // "" , want "0"
-strutil.BaseConvInt(0, 64)      // "" , want "0"
-```
-
-This is also internally inconsistent: `BaseConvInt` returns the correct `"0"`
-for small bases because it delegates to `strconv.FormatUint`/`big.Int.Text`,
-but returns `""` for bases in `(62, 64]`, which go through the template path:
-
-```go
-strutil.BaseConvInt(0, 16)      // "0"  (strconv path)
-strutil.BaseConvInt(0, 64)      // ""   (template path)
-```
-
-## Root cause
-
-`strutil/convbase.go`, `BaseConvIntByTpl`:
-
-```go
-func BaseConvIntByTpl(dec uint64, toBase string) string {
-	var res string
-	toLen := uint64(len(toBase))
-	for dec > 0 {                 // never runs when dec == 0
-		res = string(toBase[dec%toLen]) + res
-		dec /= toLen
-	}
-	return res                    // returns "" for dec == 0
-}
-```
-
-The loop condition `dec > 0` is never entered when `dec == 0`, so the function
-returns the zero-value empty string. Every public entry point that reaches the
-template path (`BaseConvIntByTpl`, `BaseConvByTpl`, `BaseConv`, `Base10Conv`,
-`BaseConvInt` for base > 62) inherits the defect.
-
-## Fix
-
-Handle the zero case explicitly by emitting the zero digit of the target base
-(the first character of the template), and guard against an empty template to
-avoid an out-of-range index:
-
-```go
-if toLen == 0 {
-	return res
-}
-if dec == 0 {
-	return string(toBase[0])
-}
-```
-
-## Test
-
-Added `TestBaseConv_zero` in `strutil/convbase_test.go` covering `BaseConv`,
-`Base10Conv`, `BaseConvInt` (small and large bases) and `BaseConvIntByTpl`.
-
-- Gate: `go test ./strutil/ -run 'TestBaseConv|TestBase10Conv'` -> ok (PASS)
-- `go vet ./strutil/` -> exit 0
-- `go build ./...` -> exit 0
-
-Counterfactual: reverting the change in `BaseConvIntByTpl` makes the new test
-fail with `actual: string("")` vs `expect: string("0")`.
-
-Note: `TestDateSNv3/dateLen4_base62` in `strutil/gensn_test.go` is flaky and
-already fails on the unmodified base commit (it asserts uniqueness of randomly
-generated serial numbers over 60 iterations); it is unrelated to this change.