cmd/cue: add new CUE_EXPERIMENT and CUE_DEBUG flags to help environment

We haven't done a very good job at keeping `cue help environment`
up to date with the actual set of flags supported by CUE_EXPERIMENT
and CUE_DEBUG via their internal packages.

While here, update the Go docs a bit so that they are consistent
with what is documented in `cue help`, and add reminders to both types
to update the help text as well.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I68e7a1a94a18de648ba850e3c4a1a2a427e441af
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1205567
TryBot-Result: CUEcueckoo <[email protected]>
Reviewed-by: Matthew Sackman <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>

Author: mvdan

cmd/cue/cmd/help.go

@@ -306,13 +306,22 @@ If an environment variable is unset or empty, sensible default setting is used.
 		decodeint64
 			Tweak cue.Value.Decode to choose "int64" rather than "int"
 			as the default Go type for CUE integer values.
+		toposort
+			Enable topological sorting of struct fields.
+			Provide feedback via https://cuelang.org/issue/3558
 
 	CUE_DEBUG
 		Comma-separated list of debug flags to enable or disable, such as:
 
 		http
 			Log a JSON message per HTTP request and response made
 			when interacting with module registries.
+		sortfields
+			Force fields in stucts to be sorted lexicographically.
+		openinline (default true)
+			Permit disallowed fields to be selected into literal struct
+			that would normally result in a close error, mimicking evalv2
+			closedness behavior in evalv3 to aid the transition.
 
 CUE_EXPERIMENT and CUE_DEBUG are comma-separated lists of key-value strings,
 where the value is a boolean "true" or "1" if omitted. For example:
@@ -321,6 +330,9 @@ where the value is a boolean "true" or "1" if omitted. For example:
 `[1:],
 }
 
+// Please keep the CUE_EXPERIMENT and CUE_DEBUG lists above in sync with
+// the cueexperiment and cuedebug packages.
+
 var modulesHelp = &cobra.Command{
 	Use:   "modules",
 	Short: "module support",

internal/cuedebug/cuedebug.go

@@ -6,10 +6,16 @@ import (
 	"cuelang.org/go/internal/envflag"
 )
 
-// Flags holds the set of CUE_DEBUG flags. It is initialized by Init.
+// Flags holds the set of global CUE_DEBUG flags. It is initialized by Init.
 var Flags Config
 
+// Flags holds the set of known CUE_DEBUG flags.
+//
+// When adding, deleting, or modifying entries below,
+// update cmd/cue/cmd/help.go as well for `cue help environment`.
 type Config struct {
+	// HTTP enables JSON logging per HTTP request and response made
+	// when interacting with module registries.
 	HTTP bool
 
 	// TODO: consider moving these evaluator-related options into a separate

internal/cueexperiment/exp.go

@@ -6,7 +6,7 @@ import (
 	"cuelang.org/go/internal/envflag"
 )
 
-// Flags holds the set of CUE_EXPERIMENT flags. It is initialized by Init.
+// Flags holds the set of global CUE_EXPERIMENT flags. It is initialized by Init.
 //
 // When adding, deleting, or modifying entries below,
 // update cmd/cue/cmd/help.go as well for `cue help environment`.
@@ -25,7 +25,7 @@ var Flags struct {
 	// to ensure consistency with 32-bit platforms.
 	DecodeInt64 bool
 
-	// Enable topological sorting of struct fields
+	// Enable topological sorting of struct fields.
 	TopoSort bool
 }