bootstrap: delay the instantiation of maps in per-context scripts

Instantiating maps renders the snapshot non-rehashable
(v8 currently fails silently during `CreateBlob()`).
Then the hash seed would always be the same and not
recomputed if custom V8 snapshot is enabled. This patch
delays the instantiation of the maps in domexception.js
and make it lazy.
PR-URL: #27371
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: joyeecheung

lib/internal/per_context/domexception.js

@@ -15,12 +15,28 @@ class ERR_INVALID_THIS extends TypeError {
 getcode(){return'ERR_INVALID_THIS';}
 }
 
-constinternalsMap=newSafeWeakMap();
+letinternalsMap;
+letnameToCodeMap;
+letisInitialized=false;
 
-constnameToCodeMap=newSafeMap();
+// We need to instantiate the maps lazily because they render
+// the snapshot non-rehashable.
+// https://bugs.chromium.org/p/v8/issues/detail?id=6593
+functionensureInitialized(){
+if(isInitialized){
+return;
+}
+internalsMap=newSafeWeakMap();
+nameToCodeMap=newSafeMap();
+forEachCode((name,codeName,value)=>{
+nameToCodeMap.set(name,value);
+});
+isInitialized=true;
+}
 
 classDOMExceptionextendsError{
 constructor(message='',name='Error'){
+ensureInitialized();
 super();
 internalsMap.set(this,{
 message: `${message}`,
@@ -29,6 +45,7 @@ class DOMException extends Error {
 }
 
 getname(){
+ensureInitialized();
 constinternals=internalsMap.get(this);
 if(internals===undefined){
 thrownewERR_INVALID_THIS('DOMException');
@@ -37,6 +54,7 @@ class DOMException extends Error {
 }
 
 getmessage(){
+ensureInitialized();
 constinternals=internalsMap.get(this);
 if(internals===undefined){
 thrownewERR_INVALID_THIS('DOMException');
@@ -45,6 +63,7 @@ class DOMException extends Error {
 }
 
 getcode(){
+ensureInitialized();
 constinternals=internalsMap.get(this);
 if(internals===undefined){
 thrownewERR_INVALID_THIS('DOMException');
@@ -61,39 +80,40 @@ Object.defineProperties(DOMException.prototype, {
 code: {enumerable: true,configurable: true}
 });
 
-for(const[name,codeName,value]of[
-['IndexSizeError','INDEX_SIZE_ERR',1],
-['DOMStringSizeError','DOMSTRING_SIZE_ERR',2],
-['HierarchyRequestError','HIERARCHY_REQUEST_ERR',3],
-['WrongDocumentError','WRONG_DOCUMENT_ERR',4],
-['InvalidCharacterError','INVALID_CHARACTER_ERR',5],
-['NoDataAllowedError','NO_DATA_ALLOWED_ERR',6],
-['NoModificationAllowedError','NO_MODIFICATION_ALLOWED_ERR',7],
-['NotFoundError','NOT_FOUND_ERR',8],
-['NotSupportedError','NOT_SUPPORTED_ERR',9],
-['InUseAttributeError','INUSE_ATTRIBUTE_ERR',10],
-['InvalidStateError','INVALID_STATE_ERR',11],
-['SyntaxError','SYNTAX_ERR',12],
-['InvalidModificationError','INVALID_MODIFICATION_ERR',13],
-['NamespaceError','NAMESPACE_ERR',14],
-['InvalidAccessError','INVALID_ACCESS_ERR',15],
-['ValidationError','VALIDATION_ERR',16],
-['TypeMismatchError','TYPE_MISMATCH_ERR',17],
-['SecurityError','SECURITY_ERR',18],
-['NetworkError','NETWORK_ERR',19],
-['AbortError','ABORT_ERR',20],
-['URLMismatchError','URL_MISMATCH_ERR',21],
-['QuotaExceededError','QUOTA_EXCEEDED_ERR',22],
-['TimeoutError','TIMEOUT_ERR',23],
-['InvalidNodeTypeError','INVALID_NODE_TYPE_ERR',24],
-['DataCloneError','DATA_CLONE_ERR',25]
+functionforEachCode(fn){
+fn('IndexSizeError','INDEX_SIZE_ERR',1);
+fn('DOMStringSizeError','DOMSTRING_SIZE_ERR',2);
+fn('HierarchyRequestError','HIERARCHY_REQUEST_ERR',3);
+fn('WrongDocumentError','WRONG_DOCUMENT_ERR',4);
+fn('InvalidCharacterError','INVALID_CHARACTER_ERR',5);
+fn('NoDataAllowedError','NO_DATA_ALLOWED_ERR',6);
+fn('NoModificationAllowedError','NO_MODIFICATION_ALLOWED_ERR',7);
+fn('NotFoundError','NOT_FOUND_ERR',8);
+fn('NotSupportedError','NOT_SUPPORTED_ERR',9);
+fn('InUseAttributeError','INUSE_ATTRIBUTE_ERR',10);
+fn('InvalidStateError','INVALID_STATE_ERR',11);
+fn('SyntaxError','SYNTAX_ERR',12);
+fn('InvalidModificationError','INVALID_MODIFICATION_ERR',13);
+fn('NamespaceError','NAMESPACE_ERR',14);
+fn('InvalidAccessError','INVALID_ACCESS_ERR',15);
+fn('ValidationError','VALIDATION_ERR',16);
+fn('TypeMismatchError','TYPE_MISMATCH_ERR',17);
+fn('SecurityError','SECURITY_ERR',18);
+fn('NetworkError','NETWORK_ERR',19);
+fn('AbortError','ABORT_ERR',20);
+fn('URLMismatchError','URL_MISMATCH_ERR',21);
+fn('QuotaExceededError','QUOTA_EXCEEDED_ERR',22);
+fn('TimeoutError','TIMEOUT_ERR',23);
+fn('InvalidNodeTypeError','INVALID_NODE_TYPE_ERR',24);
+fn('DataCloneError','DATA_CLONE_ERR',25);
 // There are some more error names, but since they don't have codes assigned,
 // we don't need to care about them.
-]){
+}
+
+forEachCode((name,codeName,value)=>{
 constdesc={enumerable: true, value };
 Object.defineProperty(DOMException,codeName,desc);
 Object.defineProperty(DOMException.prototype,codeName,desc);
-nameToCodeMap.set(name,value);
-}
+});
 
 exports.DOMException=DOMException;