cue: set DynamicLabel

For certain cases in the API the DynamicLabel needs
to be explicitly set.

Also, Template needs to recognize when Lookup
can be applied for the new evaluator.

Issue #3060

Signed-off-by: Marcel van Lohuizen <[email protected]>
Change-Id: Iad2a9ff913588ec3151ca61121aa714aa0b571f6
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1194058
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Daniel Martí <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mpvl

cue/types.go

@@ -1817,8 +1817,12 @@ func (v hiddenValue) Template() func(label string) Value {
 		return nil
 	}
 
+	// Implementation for the old evaluator.
 	types := v.v.OptionalTypes()
-	if types&(adt.HasAdditional|adt.HasPattern) == 0 {
+	switch {
+	case types&(adt.HasAdditional|adt.HasPattern) != 0:
+	case v.v.PatternConstraints != nil:
+	default:
 		return nil
 	}
 

cue/types_test.go

@@ -1850,6 +1850,8 @@ func TestTemplate(t *testing.T) {
 		value string
 		path  []string
 		want  string
+
+		skip bool
 	}{{
 		value: `
 		a: [Name=string]: Name
@@ -1881,10 +1883,14 @@ func TestTemplate(t *testing.T) {
 		`,
 		path: []string{"a", "foo", "b", ""},
 		want: `{"c":"foolabel","d":"label"}`,
+
+		skip: true, // TODO: reordering
 	}}
 	for _, tc := range testCases {
 		runMatrix(t, "", func(t *testing.T, cfg *evalConfig) {
-			TODO_V3(t, cfg)
+			if tc.skip {
+				TODO_V3(t, cfg)
+			}
 
 			v := cfg.getValue(t, tc.value)
 			for _, p := range tc.path {

internal/core/adt/composite.go

@@ -1031,6 +1031,12 @@ func (v *Vertex) MatchAndInsert(ctx *OpContext, arc *Vertex) {
 		for _, pc := range pcs.Pairs {
 			if matchPattern(ctx, pc.Pattern, arc.Label) {
 				for _, c := range pc.Constraint.Conjuncts {
+					env := *(c.Env)
+					if arc.Label.Index() < MaxIndex {
+						env.DynamicLabel = arc.Label
+					}
+					c.Env = &env
+
 					root := arc.rootCloseContext(ctx)
 					root.insertConjunct(ctx, root, c, c.CloseInfo, ArcMember, true, false)
 				}