internal/core/adt: clear close check

Builtin calls currently may still be evaluated
within a different OpContext. This means that
any closedness information attached to the
returned data is invalid. This is fine, as
regular builtin return values should be treated
as values. (This is different for non-concrete
builtins).

Note that such closedness information is still
handled correctly _within_ the builtin, and thus
there is still typo checking going on there.
Just the typo checking information of the
returned value can be ignored.

We now do this by resetting the closedness
information in newReq if we notice that the
value originates from a different context.
We introduce a helper function and use it in
other spots where the typo checking info was
previously closed.

Fixes #4000

Signed-off-by: Marcel van Lohuizen <[email protected]>
Change-Id: I0df7bc73498b6bd3cb14abc00f00d2a4038aac08
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1219265
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Daniel Martí <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mpvl

cue/testdata/definitions/issue4000.txtar

@@ -31,16 +31,10 @@ _items: [#VMRuleList]
 }
 #TypeMeta: kind: string | *"default"
 -- out/evalalpha --
-Errors:
-items: error in call to list.Sort: runtime error: index out of range [13] with length 6:
-    ./in.cue:3:8
-
-Result:
-(_|_){
-  // [eval]
-  items: (_|_){
-    // [eval] items: error in call to list.Sort: runtime error: index out of range [13] with length 6:
-    //     ./in.cue:3:8
+(struct){
+  items: (#list){
+    0: ~(#VMRuleList.0)
+    1: ~(#VMRuleList.1)
   }
   #List: (#struct){
     items: (#list){
@@ -153,16 +147,16 @@ Result:
 }
 -- out/evalalpha/stats --
 Leaks:  0
-Freed:  52
-Reused: 20
+Freed:  54
+Reused: 22
 Allocs: 32
 Retain: 0
 
-Unifications: 36
-Conjuncts:    74
+Unifications: 38
+Conjuncts:    77
 Disjuncts:    12
 
-NumCloseIDs: 16
+NumCloseIDs: 17
 -- diff/-out/evalalpha/stats<==>+out/eval/stats --
 diff old new
 --- old
@@ -177,16 +171,16 @@ diff old new
 -Unifications: 116
 -Conjuncts:    257
 -Disjuncts:    161
-+Freed:  52
-+Reused: 20
++Freed:  54
++Reused: 22
 +Allocs: 32
 +Retain: 0
 +
-+Unifications: 36
-+Conjuncts:    74
++Unifications: 38
++Conjuncts:    77
 +Disjuncts:    12
 +
-+NumCloseIDs: 16
++NumCloseIDs: 17
 -- out/eval/stats --
 Leaks:  0
 Freed:  152
@@ -201,9 +195,9 @@ Disjuncts:    161
 diff old new
 --- old
 +++ new
-@@ -1,85 +1,22 @@
--(struct){
--  items: (#list){
+@@ -1,85 +1,16 @@
+ (struct){
+   items: (#list){
 -    0: (#struct){
 -      spec: (#list){
 -        0: (#struct){
@@ -228,16 +222,8 @@ diff old new
 -      }
 -      kind: (string){ |(*(string){ "default" }, (string){ string }) }
 -    }
-+Errors:
-+items: error in call to list.Sort: runtime error: index out of range [13] with length 6:
-+    ./in.cue:3:8
-+
-+Result:
-+(_|_){
-+  // [eval]
-+  items: (_|_){
-+    // [eval] items: error in call to list.Sort: runtime error: index out of range [13] with length 6:
-+    //     ./in.cue:3:8
++    0: ~(#VMRuleList.0)
++    1: ~(#VMRuleList.1)
    }
    #List: (#struct){
      items: (#list){
@@ -300,7 +286,7 @@ diff old new
    }
    #VMRuleList: (#list){
      0: (#struct){
-@@ -115,9 +52,9 @@
+@@ -115,9 +46,9 @@
      expr: (string){ string }
    }
    #VMRule: (#struct){

internal/core/adt/composite.go

@@ -838,10 +838,7 @@ func (v *Vertex) toDataAllRec(ctx *OpContext, processed map[*Vertex]*Vertex) *Ve
 		// Always reset all CloseInfo fields to zero. Normally only the top
 		// conjuncts matter and get inserted and conjuncts of recursive arcs
 		// never come in play. ToDataAll is an exception.
-		w.Conjuncts[i].CloseInfo.opID = 0
-		w.Conjuncts[i].CloseInfo.defID = 0
-		w.Conjuncts[i].CloseInfo.outerID = 0
-		w.Conjuncts[i].CloseInfo.enclosingEmbed = 0
+		w.Conjuncts[i].CloseInfo = w.Conjuncts[i].CloseInfo.clearCloseCheck()
 	}
 
 	// Store the processed vertex before returning

internal/core/adt/typocheck.go

@@ -421,7 +421,21 @@ func (c *OpContext) subField(ci CloseInfo) CloseInfo {
 	return ci
 }
 
+// clearCloseCheck clears the CloseInfo for a node, so that it is not
+// considered for typo checking.
+func (id CloseInfo) clearCloseCheck() CloseInfo {
+	id.opID = 0
+	id.defID = 0
+	id.enclosingEmbed = 0
+	id.outerID = 0
+	return id
+}
+
 func (n *nodeContext) newReq(id CloseInfo, kind defIDType) CloseInfo {
+	if id.defID != 0 && id.opID != n.ctx.opID {
+		return id.clearCloseCheck()
+	}
+
 	dstID := n.ctx.getNextDefID()
 	n.addReplacement(replaceID{from: id.defID, to: dstID})