cmd/cue: add test case for get go with string escape codes

The added test case fails currently:

    > exec cue get go --local ./decls
    [...]
    > exec cue vet go_marshal.json schema.cue
    [stderr]
    #ErrorPrefix: invalid string: invalid syntax:
        ./decls/p_go_gen.cue:14:15
    #ResetColor: invalid string: invalid syntax:
        ./decls/p_go_gen.cue:16:14

The following commit will include the fix.

For #2915.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: Ib1882499b6c7064ad4fd60d0c1d92cf338c7e901
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1211574
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Roger Peppe <[email protected]>

Author: mvdan

cmd/cue/cmd/testdata/script/get_go_json_compat.txtar

@@ -8,13 +8,13 @@ cmp decls/p_go_gen.cue decls/p_go_gen.cue.golden
 exec go run ./marshal
 cp stdout go_marshal.json
 cmp go_marshal.json go_marshal.json.golden
-exec cue vet go_marshal.json schema.cue
+! exec cue vet go_marshal.json schema.cue
 
 # Export from CUE and Unmarshal via Go's encoding/json.
-exec cue export ./decls
-cmp stdout cue_export.json.golden
-stdin stdout
-exec go run ./unmarshal
+! exec cue export ./decls
+# cmp stdout cue_export.json.golden
+# stdin stdout
+# exec go run ./unmarshal
 
 -- schema.cue --
 package schema
@@ -35,12 +35,21 @@ package decls
 
 #Root & {
 	Duration: #ValueSecond
+
+	Strings: [
+		#ErrorPrefix,
+		#ResetColor,
+	]
 }
 -- go_marshal.json.golden --
-{"Duration":3000000000}
+{"Duration":3000000000,"Strings":["\u001b[31mError:\u001b[0m","\u001b[0m"]}
 -- cue_export.json.golden --
 {
-    "Duration": 3000000000
+    "Duration": 3000000000,
+    "Strings": [
+        "\u001b[31mError:\u001b[0m",
+        "\u001b[0m"
+    ]
 }
 -- decls/p.go --
 package decls
@@ -49,9 +58,14 @@ import "time"
 
 type Root struct {
 	Duration time.Duration
+
+	Strings []string
 }
 
 const ValueSecond = 3 * time.Second
+
+const ErrorPrefix = "\033[31mError:\033[0m"
+const ResetColor = "\u001b[0m"
 -- decls/p_go_gen.cue.golden --
 // Code generated by cue get go. DO NOT EDIT.
 
@@ -61,9 +75,14 @@ package decls
 
 #Root: {
 	Duration: int @go(,time.Duration)
+	Strings: [...string] @go(,[]string)
 }
 
 #ValueSecond: int & 3000000000
+
+#ErrorPrefix: "\x1b[31mError:\x1b[0m" // "\033[31mError:\033[0m"
+
+#ResetColor: "\x1b[0m" // "\u001b[0m"
 -- marshal/main.go --
 package main
 
@@ -76,7 +95,13 @@ import (
 )
 
 func main() {
-	r := decls.Root{Duration: decls.ValueSecond}
+	r := decls.Root{
+		Duration: decls.ValueSecond,
+		Strings: []string{
+			decls.ErrorPrefix,
+			decls.ResetColor,
+		},
+	}
 	data, err := json.Marshal(r)
 	if err != nil {
 		log.Fatal(err)