internal/core/adt: set isOuterStruct field

This is only for debugging purposes: the
visual debugger marks the ID as being used
in an CloseInfo.outerID field.

Signed-off-by: Marcel van Lohuizen <[email protected]>
Change-Id: Icbb0baaf06b660eb58cd176993170ba66c2e1312
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1212019
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Matthew Sackman <[email protected]>

Author: mpvl

internal/core/adt/debug.go

@@ -396,7 +396,7 @@ func (m *mermaidContext) vertexInfo(vc *mermaidVertex, recursive bool) {
 				format = "%s((<s><i>%d%si</i></s>))\n"
 			}
 			flags := ""
-			if d.placeholder {
+			if d.isOuterStruct {
 				flags += "S"
 			}
 			if d.exclude != 0 {

internal/core/adt/typocheck.go

@@ -184,13 +184,21 @@ func (c *OpContext) getNextDefID() defID {
 type refInfo struct {
 	v  *Vertex
 	id defID
-	// exclude
+
+	// exclude defines a subtree of CloseInfo.def that should not be
+	// transitively added to the set of allowed fields.
+	//
 	// It would probably be more efficient to track a separate allow and deny
 	// list, rather than tracking the entire tree except for the excluded.
 	exclude defID
 
-	ignore      bool
-	placeholder bool
+	// ignore defines whether we should not do typo checking for this defID.
+	ignore bool
+
+	// isOuterStruct indicates that this struct is marked as "outerID" in a
+	// CloseInfo. The debug visualization in ./debug.go uses this to show a
+	// mark ("S") next to the defID to visualize that this fact.
+	isOuterStruct bool
 }
 
 type conjunctFlags uint8
@@ -323,7 +331,7 @@ func (n *nodeContext) addResolver(v *Vertex, id CloseInfo, forceIgnore bool) Clo
 	if id.enclosingEmbed != 0 && !ignore {
 		ph := id.outerID
 		n.addReplacement(replaceID{from: dstID, to: ph, add: true})
-		id, dstID = n.newGroup(id)
+		id, dstID = n.newGroup(id, false)
 		id.enclosingEmbed = dstID
 	}
 
@@ -337,13 +345,15 @@ func (c *OpContext) subField(ci CloseInfo) CloseInfo {
 	return ci
 }
 
-func (n *nodeContext) newGroup(id CloseInfo) (CloseInfo, defID) {
+func (n *nodeContext) newGroup(id CloseInfo, placeholder bool) (CloseInfo, defID) {
 	srcID := id.defID
 	dstID := n.ctx.getNextDefID()
+	// TODO: consider only adding when record || OpenGraph
 	n.reqDefIDs = append(n.reqDefIDs, refInfo{
-		v:      emptyNode,
-		id:     dstID,
-		ignore: true,
+		v:             emptyNode,
+		id:            dstID,
+		ignore:        true,
+		isOuterStruct: placeholder,
 	})
 	id.defID = dstID
 	n.addReplacement(replaceID{from: srcID, to: dstID, add: true})
@@ -396,7 +406,7 @@ func (n *nodeContext) injectEmbedNode(x Decl, id CloseInfo) CloseInfo {
 		}
 	}
 
-	id, dstID := n.newGroup(id)
+	id, dstID := n.newGroup(id, false)
 	id.enclosingEmbed = dstID
 
 	return id
@@ -430,7 +440,7 @@ func (n *nodeContext) splitDefID(s *StructLit, id CloseInfo) CloseInfo {
 		return id
 	}
 
-	id, dstID := n.newGroup(id)
+	id, dstID := n.newGroup(id, true)
 
 	if id.outerID == 0 {
 		id.outerID = dstID