internal/core/validate: add test for issue 3651

Issue #3651

Signed-off-by: Marcel van Lohuizen <mpvl@gmail.com>
Change-Id: I0f2755389bc954828dbc11d4dd53fd4b5eb72c17
Dispatch-Trailer: {"type":"trybot","CL":1206949,"patchset":1,"ref":"refs/changes/49/1206949/1","targetBranch":"master"}

cue/testdata/cycle/builtins.txtar

@@ -126,50 +126,57 @@ issue3443: {
 		fail: #S: matchN(1, [{n: #S}]) & {n: n: n: _}
 	}
 }
+issue3633: final: {
+	// With nested matchNs as below, the schema will become an incomplete error
+	// as a value of the root vertex. Make sure this edge case is properly
+	// handled.
+	data: {} & #s
+	#s: matchN(1, [matchN(1, [{a!: _}])])
+}
 -- todo/p1 --
 issue3443.noCycle: fix hang
 -- out/evalalpha/stats --
-Leaks:  193
+Leaks:  211
 Freed:  17
 Reused: 17
-Allocs: 193
+Allocs: 211
 Retain: 0
 
-Unifications: 167
-Conjuncts:    657
+Unifications: 183
+Conjuncts:    696
 Disjuncts:    28
 -- diff/-out/evalalpha/stats<==>+out/eval/stats --
 diff old new
 --- old
 +++ new
 @@ -1,9 +1,9 @@
--Leaks:  12
--Freed:  235
--Reused: 218
+-Leaks:  14
+-Freed:  249
+-Reused: 234
 -Allocs: 29
--Retain: 65
-+Leaks:  193
+-Retain: 70
++Leaks:  211
 +Freed:  17
 +Reused: 17
-+Allocs: 193
++Allocs: 211
 +Retain: 0
 
--Unifications: 211
--Conjuncts:    389
--Disjuncts:    290
-+Unifications: 167
-+Conjuncts:    657
+-Unifications: 227
+-Conjuncts:    413
+-Disjuncts:    309
++Unifications: 183
++Conjuncts:    696
 +Disjuncts:    28
 -- out/eval/stats --
-Leaks:  12
-Freed:  235
-Reused: 218
+Leaks:  14
+Freed:  249
+Reused: 234
 Allocs: 29
-Retain: 65
+Retain: 70
 
-Unifications: 211
-Conjuncts:    389
-Disjuncts:    290
+Unifications: 227
+Conjuncts:    413
+Disjuncts:    309
 -- out/evalalpha --
 Errors:
 issue3443.matchIf.#S: cannot call non-function matchIf (type struct):
@@ -350,6 +357,20 @@ Result:
       }
     }
   }
+  issue3633: (struct){
+    final: (struct){
+      data: (#struct){
+      }
+      #s: (_){ matchN(1, (#list){
+          0: (_|_){// &[matchN(1, [
+            //   {
+            //     a!: _
+            //   },
+            // ])]
+          }
+        }) }
+    }
+  }
 }
 -- diff/-out/evalalpha<==>+out/eval --
 diff old new
@@ -476,6 +497,24 @@ diff old new
            n: (struct){
              n: (_){ _ }
            }
+@@ -167,14 +179,14 @@
+   }
+   issue3633: (struct){
+     final: (struct){
+-      data: (struct){
++      data: (#struct){
+       }
+       #s: (_){ matchN(1, (#list){
+-          0: (_|_){// matchN(1, [
++          0: (_|_){// &[matchN(1, [
+             //   {
+             //     a!: _
+             //   },
+-            // ])
++            // ])]
+           }
+         }) }
+     }
 -- diff/todo/p2 --
 issue3443: Sort out differences in reporting of cycles.
 -- out/eval --
@@ -646,6 +685,20 @@ Result:
       }
     }
   }
+  issue3633: (struct){
+    final: (struct){
+      data: (struct){
+      }
+      #s: (_){ matchN(1, (#list){
+          0: (_|_){// matchN(1, [
+            //   {
+            //     a!: _
+            //   },
+            // ])
+          }
+        }) }
+    }
+  }
 }
 -- out/compile --
 --- in.cue
@@ -786,4 +839,16 @@ Result:
       }
     }
   }
+  issue3633: {
+    final: {
+      data: ({} & 〈0;#s〉)
+      #s: matchN(1, [
+        matchN(1, [
+          {
+            a!: _
+          },
+        ]),
+      ])
+    }
+  }
 }