internal/core/runtime: select evaluator version with specific constants

Do not rely on DefaultVersion and DevVersion to represent evalv2
and evalv3, because DefaultVersion is now flipping to evalv3.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I10b46d77fa086e25a4e4c1c7f81cbb7ac24c13e0
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1212504
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Matthew Sackman <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mvdan

Diff for: internal/core/runtime/imports.go

@@ -61,9 +61,9 @@ var SharedRuntime = sync.OnceValue(func() *Runtime {
 	// or getting rid of SharedRuntime altogether.
 	cueexperiment.Init()
 	if cueexperiment.Flags.EvalV3 {
-		r.version = internal.DevVersion
+		r.version = internal.EvalV3
 	} else {
-		r.version = internal.DefaultVersion
+		r.version = internal.EvalV2
 	}
 	return r
 })

Diff for: internal/core/runtime/runtime.go

@@ -116,9 +116,9 @@ func (r *Runtime) Init() {
 
 	cueexperiment.Init()
 	if cueexperiment.Flags.EvalV3 {
-		r.version = internal.DevVersion
+		r.version = internal.EvalV3
 	} else {
-		r.version = internal.DefaultVersion
+		r.version = internal.EvalV2
 	}
 	r.topoSort = cueexperiment.Flags.TopoSort