Monomorphize allocators for tsserver/public API, just like core compi…

…ler (#58045)

src/compiler/_namespaces/ts.ts

@@ -21,6 +21,7 @@ export * from "../factory/nodeFactory";
 export * from "../factory/emitNode";
 export * from "../factory/emitHelpers";
 export * from "../factory/nodeTests";
+export * from "../factory/nodeChildren";
 export * from "../factory/utilities";
 export * from "../factory/utilitiesPublic";
 export * from "../parser";

src/compiler/factory/nodeChildren.ts

@@ -0,0 +1,19 @@
+import { Node } from "../_namespaces/ts";
+
+const nodeChildren = new WeakMap<Node, Node[] | undefined>();
+
+/** @internal */
+export function getNodeChildren(node: Node): Node[] | undefined {
+    return nodeChildren.get(node);
+}
+
+/** @internal */
+export function setNodeChildren(node: Node, children: Node[]): Node[] {
+    nodeChildren.set(node, children);
+    return children;
+}
+
+/** @internal */
+export function unsetNodeChildren(node: Node) {
+    nodeChildren.delete(node);
+}

src/compiler/factory/nodeFactory.ts

@@ -387,6 +387,7 @@ import {
     setEmitFlags,
     setIdentifierAutoGenerate,
     setIdentifierTypeArguments,
+    setNodeChildren,
     setParent,
     setTextRange,
     ShorthandPropertyAssignment,
@@ -6210,7 +6211,7 @@ export function createNodeFactory(flags: NodeFactoryFlags, baseFactory: BaseNode
     // @api
     function createSyntaxList(children: Node[]) {
         const node = createBaseNode<SyntaxList>(SyntaxKind.SyntaxList);
-        node._children = children;
+        setNodeChildren(node, children);
         return node;
     }
 

src/compiler/parser.ts

@@ -387,6 +387,7 @@ import {
     unescapeLeadingUnderscores,
     UnionOrIntersectionTypeNode,
     UnionTypeNode,
+    unsetNodeChildren,
     UpdateExpression,
     VariableDeclaration,
     VariableDeclarationList,
@@ -10002,9 +10003,7 @@ namespace IncrementalParser {
 
             // Ditch any existing LS children we may have created.  This way we can avoid
             // moving them forward.
-            if (node._children) {
-                node._children = undefined;
-            }
+            unsetNodeChildren(node);
 
             setTextRangePosEnd(node, node.pos + delta, node.end + delta);
 
@@ -10160,7 +10159,7 @@ namespace IncrementalParser {
             const fullEnd = child.end;
             if (fullEnd >= changeStart) {
                 child.intersectsChange = true;
-                child._children = undefined;
+                unsetNodeChildren(child);
 
                 // Adjust the pos or end (or both) of the intersecting element accordingly.
                 adjustIntersectingElement(child, changeStart, changeRangeOldEnd, changeRangeNewEnd, delta);
@@ -10349,7 +10348,6 @@ namespace IncrementalParser {
 
     export interface IncrementalNode extends Node, IncrementalElement {
         hasBeenIncrementallyParsed: boolean;
-        _children: Node[] | undefined;
     }
 
     interface IncrementalNodeArray extends NodeArray<IncrementalNode>, IncrementalElement {

src/compiler/types.ts

@@ -9695,7 +9695,6 @@ export interface DiagnosticCollection {
 // SyntaxKind.SyntaxList
 export interface SyntaxList extends Node {
     kind: SyntaxKind.SyntaxList;
-    _children: Node[];
 }
 
 // dprint-ignore

src/compiler/utilities.ts

@@ -188,6 +188,7 @@ import {
     getLineStarts,
     getModeForUsageLocation,
     getNameOfDeclaration,
+    getNodeChildren,
     getNormalizedAbsolutePath,
     getNormalizedPathComponents,
     getOwnKeys,
@@ -511,7 +512,6 @@ import {
     SymbolFlags,
     SymbolTable,
     SyntaxKind,
-    SyntaxList,
     TaggedTemplateExpression,
     TemplateExpression,
     TemplateLiteral,
@@ -1162,8 +1162,11 @@ export function getTokenPosOfNode(node: Node, sourceFile?: SourceFileLike, inclu
     // the syntax list itself considers them as normal trivia. Therefore if we simply skip
     // trivia for the list, we may have skipped the JSDocComment as well. So we should process its
     // first child to determine the actual position of its first token.
-    if (node.kind === SyntaxKind.SyntaxList && (node as SyntaxList)._children.length > 0) {
-        return getTokenPosOfNode((node as SyntaxList)._children[0], sourceFile, includeJsDoc);
+    if (node.kind === SyntaxKind.SyntaxList) {
+        const first = firstOrUndefined(getNodeChildren(node));
+        if (first) {
+            return getTokenPosOfNode(first, sourceFile, includeJsDoc);
+        }
     }
 
     return skipTrivia(
@@ -8155,6 +8158,7 @@ export interface ObjectAllocator {
 }
 
 function Symbol(this: Symbol, flags: SymbolFlags, name: __String) {
+    // Note: if modifying this, be sure to update SymbolObject in src/services/services.ts
     this.flags = flags;
     this.escapedName = name;
     this.declarations = undefined;
@@ -8172,20 +8176,23 @@ function Symbol(this: Symbol, flags: SymbolFlags, name: __String) {
 }
 
 function Type(this: Type, checker: TypeChecker, flags: TypeFlags) {
+    // Note: if modifying this, be sure to update TypeObject in src/services/services.ts
     this.flags = flags;
     if (Debug.isDebugging || tracing) {
         this.checker = checker;
     }
 }
 
 function Signature(this: Signature, checker: TypeChecker, flags: SignatureFlags) {
+    // Note: if modifying this, be sure to update SignatureObject in src/services/services.ts
     this.flags = flags;
     if (Debug.isDebugging) {
         this.checker = checker;
     }
 }
 
 function Node(this: Mutable<Node>, kind: SyntaxKind, pos: number, end: number) {
+    // Note: if modifying this, be sure to update NodeObject in src/services/services.ts
     this.pos = pos;
     this.end = end;
     this.kind = kind;
@@ -8199,6 +8206,7 @@ function Node(this: Mutable<Node>, kind: SyntaxKind, pos: number, end: number) {
 }
 
 function Token(this: Mutable<Node>, kind: SyntaxKind, pos: number, end: number) {
+    // Note: if modifying this, be sure to update TokenOrIdentifierObject in src/services/services.ts
     this.pos = pos;
     this.end = end;
     this.kind = kind;
@@ -8210,6 +8218,7 @@ function Token(this: Mutable<Node>, kind: SyntaxKind, pos: number, end: number)
 }
 
 function Identifier(this: Mutable<Node>, kind: SyntaxKind, pos: number, end: number) {
+    // Note: if modifying this, be sure to update TokenOrIdentifierObject in src/services/services.ts
     this.pos = pos;
     this.end = end;
     this.kind = kind;
@@ -8222,6 +8231,7 @@ function Identifier(this: Mutable<Node>, kind: SyntaxKind, pos: number, end: num
 }
 
 function SourceMapSource(this: SourceMapSource, fileName: string, text: string, skipTrivia?: (pos: number) => number) {
+    // Note: if modifying this, be sure to update SourceMapSourceObject in src/services/services.ts
     this.fileName = fileName;
     this.text = text;
     this.skipTrivia = skipTrivia || (pos => pos);