all: clean up some TODOs for old Go versions

Now that we require Go 1.20 or later, we can simplify some of our code.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: Iede54cc9b67806a5c4de8cffc88903e838106186
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1167670
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Roger Peppe <[email protected]>

cue/ast/astutil/sanitize.go

@@ -332,9 +332,8 @@ func (z *sanitizer) uniqueName(base string, hidden bool) string {
 		}
 	}
 
-	// TODO(go1.13): const mask = 0xff_ffff_ffff_ffff
-	const mask = 0xffffffffffffff // max bits; stay clear of int64 overflow
-	const shift = 4               // rate of growth
+	const mask = 0xff_ffff_ffff_ffff // max bits; stay clear of int64 overflow
+	const shift = 4                  // rate of growth
 	for n := int64(0x10); ; n = int64(mask&((n<<shift)-1)) + 1 {
 		num := z.rand.Intn(int(n))
 		name := fmt.Sprintf("%s_%01X", base, num)

encoding/gocode/templates.go

@@ -15,7 +15,6 @@
 package gocode
 
 import (
-	"strings"
 	"text/template"
 )
 
@@ -36,14 +35,6 @@ import (
 
 `))
 
-// normalizeHex copes with differences between the Go string literal conventions
-// between go1.18 and go1.19. The byte 0x7f changed from \u007f to \x7f.
-// By normalizing here, we make the code generation independent of the Go
-// version that's used.
-func normalizeHex(s string) string {
-	return strings.ReplaceAll(s, `\u007f`, `\x7f`)
-}
-
 // Inputs:
 // .prefix 	  prefix to all generated variable names
 // .cueName   name of the top-level CUE value
@@ -75,9 +66,7 @@ func {{if .func}}{{.complete}}{{.cueName}}{{$sig}}
 // .prefix 	  prefix to all generated variable names
 // .runtime   the variable name of a user-supplied runtime, if any
 // .data      bytes obtained from Instance.MarshalBinary
-var loadCode = template.Must(template.New("load").Funcs(template.FuncMap{
-	"normalizeHex": normalizeHex,
-}).Parse(`
+var loadCode = template.Must(template.New("load").Parse(`
 var {{.prefix}}Codec, {{.prefix}}Instance_, {{.prefix}}Value = func() (*gocodec.Codec, *cue.Instance, cue.Value) {
 	var r *cue.Runtime
 	r = {{if .runtime}}{{.runtime}}{{else}}&cue.Runtime{}{{end}}
@@ -113,5 +102,5 @@ func {{.prefix}}Make(name string, x interface{}) cue.Value {
 }
 
 // Data size: {{len .data}} bytes.
-var {{.prefix}}InstanceData = []byte({{printf "%+q" .data | normalizeHex }})
+var {{.prefix}}InstanceData = []byte({{printf "%+q" .data }})
 `))

pkg/time/time_test.go

@@ -35,6 +35,13 @@ func TestTimestamp(t *testing.T) {
 
 		// TODO: allow leap seconds? This is allowed by the RFC 3339 spec.
 		// `"2019-06-30T23:59:60Z"`, // leap seconds
+
+		// NOTE: Go 1.17 rejected the extra digits,
+		// and Go 1.18 started accepting them while discarding them.
+		// We want CUE to be consistent across Go versions,
+		// so we should probably fork Go's time package to behave exactly the
+		// way we want and in a consistent way across Go versions.
+		`"2019-01-02T15:04:05.01234567890-08:00"`,
 	}
 
 	for _, tc := range validTimes {
@@ -71,15 +78,6 @@ func TestTimestamp(t *testing.T) {
 		`"2019-13-15T23:00:00Z"`,       // month out of range
 		`"2019-01-02T15:04:05Z+08:00"`, // double time zone
 		`"2019-01-02T15:04:05+08"`,     // partial time zone
-
-		// TODO: Go 1.17 rejected the extra digits,
-		// and Go 1.18 started accepting them while discarding them.
-		// We want CUE to be consistent across Go versions,
-		// so we should probably fork Go's time package to behave exactly the
-		// way we want and in a consistent way across Go versions.
-		// In the meantime, having newer Go versions accept more inputs is not a
-		// terrible state of affairs, so for now we disable the test case.
-		// `"2019-01-02T15:04:05.01234567890-08:00"`,
 	}
 
 	for _, tc := range invalidTimes {