add comments for v7

consider removing minimal level of pruning built into healSchema and mapSchema in the next major version, as built in pruning makes it impossible to build unpruned schemas, which may be of use to some library users

packages/utils/src/heal.ts

@@ -121,6 +121,9 @@ export function healTypes(
   }
 
   if (!config.skipPruning) {
+    // TODO:
+    // consider removing the default level of pruning in v7,
+    // see comments below on the pruneTypes function.
     pruneTypes(originalTypeMap, directives);
   }
 
@@ -220,6 +223,14 @@ export function healTypes(
   }
 }
 
+// TODO:
+// consider removing the default level of pruning in v7
+//
+// Pruning was introduced into healSchema in v5, so legacy schema directives relying on pruning
+// during healing are likely to be rare. pruning is now recommended via the dedicated pruneSchema
+// function which does not force pruning on library users and gives granular control in terms of
+// pruning types. pruneSchema does recreate the schema -- a parallel version that prunes in place
+// could be considered.
 function pruneTypes(typeMap: Record<string, GraphQLNamedType | null>, directives: ReadonlyArray<GraphQLDirective>) {
   const implementedInterfaces = {};
   Object.values(typeMap).forEach(namedType => {

packages/utils/src/rewire.ts

@@ -67,6 +67,9 @@ export function rewireTypes(
 
   const newDirectives = directives.map(directive => rewireDirective(directive));
 
+  // TODO:
+  // consider removing the default level of pruning in v7,
+  // see comments below on the pruneTypes function.
   return options.skipPruning
     ? {
         typeMap: newTypeMap,
@@ -199,6 +202,13 @@ export function rewireTypes(
   }
 }
 
+// TODO:
+// consider removing the default level of pruning in v7
+//
+// Pruning during mapSchema limits the ability to create an unpruned schema, which may be of use
+// to some library users. pruning is now recommended via the dedicated pruneSchema function
+// which does not force pruning on library users and gives granular control in terms of pruning
+// types.
 function pruneTypes(
   typeMap: TypeMap,
   directives: Array<GraphQLDirective>