From cd3afe4f0c261f65404c230f22ab555a761cb1b4 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Mon, 23 Jan 2023 19:31:30 -0800
Subject: [PATCH 1/9] Reuse Printers in symbolToStringWorker

---
 src/compiler/checker.ts |  9 ++++++++-
 src/compiler/core.ts    | 30 ++++++++++++++++++++++++++++++
 src/compiler/emitter.ts |  3 ++-
 src/compiler/types.ts   |  1 +
 4 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 9f77641faf5cc..020c509a96526 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -871,6 +871,7 @@ import {
     pathIsRelative,
     PatternAmbientModule,
     PlusToken,
+    pooled,
     PostfixUnaryExpression,
     PrefixUnaryExpression,
     PrivateIdentifier,
@@ -2173,6 +2174,9 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         [".json", ".json"],
     ];
 
+    const symbolToStringWorkerSourceFilePrinter = pooled(() => createPrinter({ removeComments: true, neverAsciiEscape: true }), (printer) => printer.reset());
+    const symbolToStringWorkerNonSourceFilePrinter = pooled(() => createPrinter({ removeComments: true }), (printer) => printer.reset());
+
     initializeTypeChecker();
 
     return checker;
@@ -6123,9 +6127,12 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         function symbolToStringWorker(writer: EmitTextWriter) {
             const entity = builder(symbol, meaning!, enclosingDeclaration, nodeFlags)!; // TODO: GH#18217
             // add neverAsciiEscape for GH#39027
-            const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile ? createPrinter({ removeComments: true, neverAsciiEscape: true }) : createPrinter({ removeComments: true });
+            const [printer, disposePrinter] = enclosingDeclaration?.kind === SyntaxKind.SourceFile
+                ? symbolToStringWorkerSourceFilePrinter()
+                : symbolToStringWorkerNonSourceFilePrinter();
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, entity, /*sourceFile*/ sourceFile, writer);
+            disposePrinter();
             return writer;
         }
     }
diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index 2dc7f533c766a..b308c8e2c3ffa 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -2917,3 +2917,33 @@ export function isNodeLikeSystem(): boolean {
         && !process.browser
         && typeof module === "object";
 }
+
+/** @internal */
+export function pooled<T>(fn: () => T, reset: (value: T) => void): () => [value: T, dispose: () => void] {
+    // TODO(jakebailey): this is supposed to be something like Go's sync.Pool,
+    // but I don't know of a way to "eventually" return the pool's contents to GC.
+    // For now, this just holds onto the objects even when they may not have been
+    // in use for a long time.
+    const pool: T[] = [];
+
+    return () => {
+        let value: T;
+        if (pool.length > 1) {
+            const end = pool.length - 1;
+            value = pool[end];
+            pool.length = end;
+        }
+        else {
+            value = fn();
+        }
+
+        const dispose = () => {
+            if (pool.length < 8) {
+                reset(value);
+                pool.push(value);
+            }
+        };
+
+        return [value, dispose];
+    };
+}
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 170ad79e7d587..1266772ba801d 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1428,7 +1428,8 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         writeList,
         writeFile,
         writeBundle,
-        bundleFileInfo
+        bundleFileInfo,
+        reset,
     };
 
     function printNode(hint: EmitHint, node: Node, sourceFile: SourceFile): string {
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 0a43afe978ea4..758fa517c0b40 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -9165,6 +9165,7 @@ export interface Printer {
     /** @internal */ writeFile(sourceFile: SourceFile, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined): void;
     /** @internal */ writeBundle(bundle: Bundle, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined): void;
     /** @deprecated @internal */ bundleFileInfo?: BundleFileInfo;
+    /** @internal */ reset(): void;
 }
 
 /** @deprecated @internal */

From db730c9c6ec5e245eba809411694dee9b2dc0f5d Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Mon, 23 Jan 2023 20:11:08 -0800
Subject: [PATCH 2/9] Simplify greatly

---
 src/compiler/checker.ts |  8 +++-----
 src/compiler/core.ts    | 30 ------------------------------
 2 files changed, 3 insertions(+), 35 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 020c509a96526..c69ac537836b6 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -871,7 +871,6 @@ import {
     pathIsRelative,
     PatternAmbientModule,
     PlusToken,
-    pooled,
     PostfixUnaryExpression,
     PrefixUnaryExpression,
     PrivateIdentifier,
@@ -2174,8 +2173,8 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         [".json", ".json"],
     ];
 
-    const symbolToStringWorkerSourceFilePrinter = pooled(() => createPrinter({ removeComments: true, neverAsciiEscape: true }), (printer) => printer.reset());
-    const symbolToStringWorkerNonSourceFilePrinter = pooled(() => createPrinter({ removeComments: true }), (printer) => printer.reset());
+    const symbolToStringWorkerSourceFilePrinter = memoize(() => createPrinter({ removeComments: true, neverAsciiEscape: true }));
+    const symbolToStringWorkerNonSourceFilePrinter = memoize(() => createPrinter({ removeComments: true }));
 
     initializeTypeChecker();
 
@@ -6127,12 +6126,11 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         function symbolToStringWorker(writer: EmitTextWriter) {
             const entity = builder(symbol, meaning!, enclosingDeclaration, nodeFlags)!; // TODO: GH#18217
             // add neverAsciiEscape for GH#39027
-            const [printer, disposePrinter] = enclosingDeclaration?.kind === SyntaxKind.SourceFile
+            const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile
                 ? symbolToStringWorkerSourceFilePrinter()
                 : symbolToStringWorkerNonSourceFilePrinter();
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, entity, /*sourceFile*/ sourceFile, writer);
-            disposePrinter();
             return writer;
         }
     }
diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index b308c8e2c3ffa..2dc7f533c766a 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -2917,33 +2917,3 @@ export function isNodeLikeSystem(): boolean {
         && !process.browser
         && typeof module === "object";
 }
-
-/** @internal */
-export function pooled<T>(fn: () => T, reset: (value: T) => void): () => [value: T, dispose: () => void] {
-    // TODO(jakebailey): this is supposed to be something like Go's sync.Pool,
-    // but I don't know of a way to "eventually" return the pool's contents to GC.
-    // For now, this just holds onto the objects even when they may not have been
-    // in use for a long time.
-    const pool: T[] = [];
-
-    return () => {
-        let value: T;
-        if (pool.length > 1) {
-            const end = pool.length - 1;
-            value = pool[end];
-            pool.length = end;
-        }
-        else {
-            value = fn();
-        }
-
-        const dispose = () => {
-            if (pool.length < 8) {
-                reset(value);
-                pool.push(value);
-            }
-        };
-
-        return [value, dispose];
-    };
-}

From 93039027d3268c844fa8cd18b7566576ff035de0 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Mon, 23 Jan 2023 20:11:44 -0800
Subject: [PATCH 3/9] Remove reset in API

---
 src/compiler/emitter.ts | 1 -
 src/compiler/types.ts   | 1 -
 2 files changed, 2 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 1266772ba801d..5ed6de9b5dbc2 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1429,7 +1429,6 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         writeFile,
         writeBundle,
         bundleFileInfo,
-        reset,
     };
 
     function printNode(hint: EmitHint, node: Node, sourceFile: SourceFile): string {
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 758fa517c0b40..0a43afe978ea4 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -9165,7 +9165,6 @@ export interface Printer {
     /** @internal */ writeFile(sourceFile: SourceFile, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined): void;
     /** @internal */ writeBundle(bundle: Bundle, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined): void;
     /** @deprecated @internal */ bundleFileInfo?: BundleFileInfo;
-    /** @internal */ reset(): void;
 }
 
 /** @deprecated @internal */

From 8610e66631d59a38677b8d940010c7815f8e3c56 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Mon, 23 Jan 2023 20:13:14 -0800
Subject: [PATCH 4/9] Minimize diff

---
 src/compiler/emitter.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 5ed6de9b5dbc2..170ad79e7d587 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1428,7 +1428,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         writeList,
         writeFile,
         writeBundle,
-        bundleFileInfo,
+        bundleFileInfo
     };
 
     function printNode(hint: EmitHint, node: Node, sourceFile: SourceFile): string {

From 6d99c8f7c99b0231092c1a849bee30d556db4d18 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Mon, 23 Jan 2023 20:36:59 -0800
Subject: [PATCH 5/9] Reuse a lot more printers

---
 src/compiler/checker.ts       | 19 +++++++++----------
 src/compiler/emitter.ts       | 12 ++++++++++++
 src/services/callHierarchy.ts |  4 ++--
 src/services/inlayHints.ts    |  6 ++----
 src/services/signatureHelp.ts |  8 ++++----
 src/services/utilities.ts     |  4 ++--
 6 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index c69ac537836b6..985893023a30b 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -111,7 +111,10 @@ import {
     createGetCanonicalFileName,
     createGetSymbolWalker,
     createModeAwareCacheKey,
-    createPrinter,
+    createPrinterWithDefaults,
+    createPrinterWithRemoveComments,
+    createPrinterWithRemoveCommentsNeverAsciiEscape,
+    createPrinterWithRemoveCommentsOmitTrailingSemicolon,
     createPropertyNameNodeForIdentifierOrLiteral,
     createSymbolTable,
     createTextWriter,
@@ -2173,9 +2176,6 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         [".json", ".json"],
     ];
 
-    const symbolToStringWorkerSourceFilePrinter = memoize(() => createPrinter({ removeComments: true, neverAsciiEscape: true }));
-    const symbolToStringWorkerNonSourceFilePrinter = memoize(() => createPrinter({ removeComments: true }));
-
     initializeTypeChecker();
 
     return checker;
@@ -6127,8 +6127,8 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             const entity = builder(symbol, meaning!, enclosingDeclaration, nodeFlags)!; // TODO: GH#18217
             // add neverAsciiEscape for GH#39027
             const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile
-                ? symbolToStringWorkerSourceFilePrinter()
-                : symbolToStringWorkerNonSourceFilePrinter();
+                ? createPrinterWithRemoveCommentsNeverAsciiEscape()
+                : createPrinterWithRemoveComments();
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, entity, /*sourceFile*/ sourceFile, writer);
             return writer;
@@ -6147,7 +6147,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 sigOutput = kind === SignatureKind.Construct ? SyntaxKind.ConstructSignature : SyntaxKind.CallSignature;
             }
             const sig = nodeBuilder.signatureToSignatureDeclaration(signature, sigOutput, enclosingDeclaration, toNodeBuilderFlags(flags) | NodeBuilderFlags.IgnoreErrors | NodeBuilderFlags.WriteTypeParametersInQualifiedName);
-            const printer = createPrinter({ removeComments: true, omitTrailingSemicolon: true });
+            const printer = createPrinterWithRemoveCommentsOmitTrailingSemicolon();
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, sig!, /*sourceFile*/ sourceFile, getTrailingSemicolonDeferringWriter(writer)); // TODO: GH#18217
             return writer;
@@ -6160,8 +6160,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         if (typeNode === undefined) return Debug.fail("should always get typenode");
         // The unresolved type gets a synthesized comment on `any` to hint to users that it's not a plain `any`.
         // Otherwise, we always strip comments out.
-        const options = { removeComments: type !== unresolvedType };
-        const printer = createPrinter(options);
+        const printer = type !== unresolvedType ? createPrinterWithRemoveComments() : createPrinterWithDefaults();
         const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
         printer.writeNode(EmitHint.Unspecified, typeNode, /*sourceFile*/ sourceFile, writer);
         const result = writer.getText();
@@ -9641,7 +9640,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 typePredicate.kind === TypePredicateKind.Identifier || typePredicate.kind === TypePredicateKind.AssertsIdentifier ? factory.createIdentifier(typePredicate.parameterName) : factory.createThisTypeNode(),
                 typePredicate.type && nodeBuilder.typeToTypeNode(typePredicate.type, enclosingDeclaration, toNodeBuilderFlags(flags) | NodeBuilderFlags.IgnoreErrors | NodeBuilderFlags.WriteTypeParametersInQualifiedName)! // TODO: GH#18217
             );
-            const printer = createPrinter({ removeComments: true });
+            const printer = createPrinterWithRemoveComments();
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, predicate, /*sourceFile*/ sourceFile, writer);
             return writer;
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 170ad79e7d587..e81f2b090a8ae 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1343,6 +1343,18 @@ const enum PipelinePhase {
     Emit,
 }
 
+/** @internal */
+export const createPrinterWithDefaults = memoize(() => createPrinter({}));
+
+/** @internal */
+export const createPrinterWithRemoveComments = memoize(() => createPrinter({ removeComments: true }));
+
+/** @internal */
+export const createPrinterWithRemoveCommentsNeverAsciiEscape = memoize(() => createPrinter({ removeComments: true, neverAsciiEscape: true }));
+
+/** @internal */
+export const createPrinterWithRemoveCommentsOmitTrailingSemicolon = memoize(() => createPrinter({ removeComments: true, omitTrailingSemicolon: true }));
+
 export function createPrinter(printerOptions: PrinterOptions = {}, handlers: PrintHandlers = {}): Printer {
     const {
         hasGlobalName,
diff --git a/src/services/callHierarchy.ts b/src/services/callHierarchy.ts
index fc4280802ee6d..a2d32e6da717f 100644
--- a/src/services/callHierarchy.ts
+++ b/src/services/callHierarchy.ts
@@ -14,7 +14,7 @@ import {
     ClassLikeDeclaration,
     ClassStaticBlockDeclaration,
     compareStringsCaseSensitive,
-    createPrinter,
+    createPrinterWithRemoveCommentsOmitTrailingSemicolon,
     createTextRangeFromNode,
     createTextSpanFromBounds,
     createTextSpanFromRange,
@@ -245,7 +245,7 @@ function getCallHierarchyItemName(program: Program, node: CallHierarchyDeclarati
     }
     if (text === undefined) {
         // get the text from printing the node on a single line without comments...
-        const printer = createPrinter({ removeComments: true, omitTrailingSemicolon: true });
+        const printer = createPrinterWithRemoveCommentsOmitTrailingSemicolon();
         text = usingSingleLineStringWriter(writer => printer.writeNode(EmitHint.Unspecified, node, node.getSourceFile(), writer));
     }
     return { text, pos: declName.getStart(), end: declName.getEnd() };
diff --git a/src/services/inlayHints.ts b/src/services/inlayHints.ts
index 5544aaa920c02..49b113e927554 100644
--- a/src/services/inlayHints.ts
+++ b/src/services/inlayHints.ts
@@ -2,7 +2,7 @@ import {
     __String,
     ArrowFunction,
     CallExpression,
-    createPrinter,
+    createPrinterWithRemoveComments,
     Debug,
     EmitHint,
     EnumMember,
@@ -53,7 +53,6 @@ import {
     NodeBuilderFlags,
     ParameterDeclaration,
     PrefixUnaryExpression,
-    PrinterOptions,
     PropertyDeclaration,
     Signature,
     skipParentheses,
@@ -383,8 +382,7 @@ export function provideInlayHints(context: InlayHintsContext): InlayHint[] {
 
     function printTypeInSingleLine(type: Type) {
         const flags = NodeBuilderFlags.IgnoreErrors | TypeFormatFlags.AllowUniqueESSymbolType | TypeFormatFlags.UseAliasDefinedOutsideCurrentScope;
-        const options: PrinterOptions = { removeComments: true };
-        const printer = createPrinter(options);
+        const printer = createPrinterWithRemoveComments();
 
         return usingSingleLineStringWriter(writer => {
             const typeNode = checker.typeToTypeNode(type, /*enclosingDeclaration*/ undefined, flags);
diff --git a/src/services/signatureHelp.ts b/src/services/signatureHelp.ts
index f662021481c4c..c8923140c4935 100644
--- a/src/services/signatureHelp.ts
+++ b/src/services/signatureHelp.ts
@@ -7,7 +7,7 @@ import {
     CheckFlags,
     contains,
     countWhere,
-    createPrinter,
+    createPrinterWithRemoveComments,
     createTextSpan,
     createTextSpanFromBounds,
     createTextSpanFromNode,
@@ -659,7 +659,7 @@ function createTypeHelpItems(
 function getTypeHelpItem(symbol: Symbol, typeParameters: readonly TypeParameter[], checker: TypeChecker, enclosingDeclaration: Node, sourceFile: SourceFile): SignatureHelpItem {
     const typeSymbolDisplay = symbolToDisplayParts(checker, symbol);
 
-    const printer = createPrinter({ removeComments: true });
+    const printer = createPrinterWithRemoveComments();
     const parameters = typeParameters.map(t => createSignatureHelpParameterForTypeParameter(t, checker, enclosingDeclaration, sourceFile, printer));
 
     const documentation = symbol.getDocumentationComment(checker);
@@ -699,7 +699,7 @@ interface SignatureHelpItemInfo { readonly isVariadic: boolean; readonly paramet
 
 function itemInfoForTypeParameters(candidateSignature: Signature, checker: TypeChecker, enclosingDeclaration: Node, sourceFile: SourceFile): SignatureHelpItemInfo[] {
     const typeParameters = (candidateSignature.target || candidateSignature).typeParameters;
-    const printer = createPrinter({ removeComments: true });
+    const printer = createPrinterWithRemoveComments();
     const parameters = (typeParameters || emptyArray).map(t => createSignatureHelpParameterForTypeParameter(t, checker, enclosingDeclaration, sourceFile, printer));
     const thisParameter = candidateSignature.thisParameter ? [checker.symbolToParameterDeclaration(candidateSignature.thisParameter, enclosingDeclaration, signatureHelpNodeBuilderFlags)!] : [];
 
@@ -713,7 +713,7 @@ function itemInfoForTypeParameters(candidateSignature: Signature, checker: TypeC
 }
 
 function itemInfoForParameters(candidateSignature: Signature, checker: TypeChecker, enclosingDeclaration: Node, sourceFile: SourceFile): SignatureHelpItemInfo[] {
-    const printer = createPrinter({ removeComments: true });
+    const printer = createPrinterWithRemoveComments();
     const typeParameterParts = mapToDisplayParts(writer => {
         if (candidateSignature.typeParameters && candidateSignature.typeParameters.length) {
             const args = factory.createNodeArray(candidateSignature.typeParameters.map(p => checker.typeParameterToDeclaration(p, enclosingDeclaration, signatureHelpNodeBuilderFlags)!));
diff --git a/src/services/utilities.ts b/src/services/utilities.ts
index e3de3b3014744..9935d419b2c4b 100644
--- a/src/services/utilities.ts
+++ b/src/services/utilities.ts
@@ -30,7 +30,7 @@ import {
     ConditionalExpression,
     contains,
     ContextFlags,
-    createPrinter,
+    createPrinterWithRemoveCommentsOmitTrailingSemicolon,
     createRange,
     createScanner,
     createTextSpan,
@@ -2984,7 +2984,7 @@ export function signatureToDisplayParts(typechecker: TypeChecker, signature: Sig
 export function nodeToDisplayParts(node: Node, enclosingDeclaration: Node): SymbolDisplayPart[] {
     const file = enclosingDeclaration.getSourceFile();
     return mapToDisplayParts(writer => {
-        const printer = createPrinter({ removeComments: true, omitTrailingSemicolon: true });
+        const printer = createPrinterWithRemoveCommentsOmitTrailingSemicolon();
         printer.writeNode(EmitHint.Unspecified, node, file, writer);
     });
 }

From 4102e953faf39bcf98ee0d59427db5349412787b Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Tue, 24 Jan 2023 10:40:11 -0800
Subject: [PATCH 6/9] Reuse new createPrinter functions in symbolDisplay

---
 src/services/symbolDisplay.ts | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/src/services/symbolDisplay.ts b/src/services/symbolDisplay.ts
index bda7ba595090c..be2e83a48bb2f 100644
--- a/src/services/symbolDisplay.ts
+++ b/src/services/symbolDisplay.ts
@@ -5,7 +5,7 @@ import {
     CallExpression,
     CheckFlags,
     contains,
-    createPrinter,
+    createPrinterWithRemoveComments,
     Debug,
     displayPart,
     EmitHint,
@@ -75,7 +75,6 @@ import {
     NodeBuilderFlags,
     ObjectFlags,
     operatorPart,
-    Printer,
     PropertyAccessExpression,
     PropertyDeclaration,
     punctuationPart,
@@ -259,7 +258,6 @@ export function getSymbolDisplayPartsDocumentationAndSymbolKind(typeChecker: Typ
     let hasAddedSymbolInfo = false;
     const isThisExpression = location.kind === SyntaxKind.ThisKeyword && isInExpressionContext(location) || isThisInTypeQuery(location);
     let type: Type | undefined;
-    let printer: Printer;
     let documentationFromAlias: SymbolDisplayPart[] | undefined;
     let tagsFromAlias: JSDocTagInfo[] | undefined;
     let hasMultipleSignatures = false;
@@ -730,10 +728,7 @@ export function getSymbolDisplayPartsDocumentationAndSymbolKind(typeChecker: Typ
     return { displayParts, documentation, symbolKind, tags: tags.length === 0 ? undefined : tags };
 
     function getPrinter() {
-        if (!printer) {
-            printer = createPrinter({ removeComments: true });
-        }
-        return printer;
+        return createPrinterWithRemoveComments();
     }
 
     function prefixNextMeaning() {

From 28dfb919a032fdea9ac9b0d41711369b1628d4bc Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Tue, 24 Jan 2023 13:04:17 -0800
Subject: [PATCH 7/9] Use a cache with a key on subset of options

---
 src/compiler/checker.ts       | 16 +++++++---------
 src/compiler/emitter.ts       | 24 ++++++++++++++++++------
 src/services/callHierarchy.ts |  4 ++--
 src/services/completions.ts   |  3 ++-
 src/services/inlayHints.ts    |  4 ++--
 src/services/signatureHelp.ts |  8 ++++----
 src/services/symbolDisplay.ts |  4 ++--
 src/services/utilities.ts     |  4 ++--
 8 files changed, 39 insertions(+), 28 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 985893023a30b..32cf2fa054ef1 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -111,10 +111,7 @@ import {
     createGetCanonicalFileName,
     createGetSymbolWalker,
     createModeAwareCacheKey,
-    createPrinterWithDefaults,
-    createPrinterWithRemoveComments,
-    createPrinterWithRemoveCommentsNeverAsciiEscape,
-    createPrinterWithRemoveCommentsOmitTrailingSemicolon,
+    createOrReusePrinter,
     createPropertyNameNodeForIdentifierOrLiteral,
     createSymbolTable,
     createTextWriter,
@@ -6127,8 +6124,8 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             const entity = builder(symbol, meaning!, enclosingDeclaration, nodeFlags)!; // TODO: GH#18217
             // add neverAsciiEscape for GH#39027
             const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile
-                ? createPrinterWithRemoveCommentsNeverAsciiEscape()
-                : createPrinterWithRemoveComments();
+                ? createOrReusePrinter({ removeComments: true, neverAsciiEscape: true })
+                : createOrReusePrinter({ removeComments: true });
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, entity, /*sourceFile*/ sourceFile, writer);
             return writer;
@@ -6147,7 +6144,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 sigOutput = kind === SignatureKind.Construct ? SyntaxKind.ConstructSignature : SyntaxKind.CallSignature;
             }
             const sig = nodeBuilder.signatureToSignatureDeclaration(signature, sigOutput, enclosingDeclaration, toNodeBuilderFlags(flags) | NodeBuilderFlags.IgnoreErrors | NodeBuilderFlags.WriteTypeParametersInQualifiedName);
-            const printer = createPrinterWithRemoveCommentsOmitTrailingSemicolon();
+            const printer = createOrReusePrinter({ removeComments: true, omitTrailingSemicolon: true });
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, sig!, /*sourceFile*/ sourceFile, getTrailingSemicolonDeferringWriter(writer)); // TODO: GH#18217
             return writer;
@@ -6160,7 +6157,8 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         if (typeNode === undefined) return Debug.fail("should always get typenode");
         // The unresolved type gets a synthesized comment on `any` to hint to users that it's not a plain `any`.
         // Otherwise, we always strip comments out.
-        const printer = type !== unresolvedType ? createPrinterWithRemoveComments() : createPrinterWithDefaults();
+        const options = { removeComments: type !== unresolvedType };
+        const printer = createOrReusePrinter(options);
         const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
         printer.writeNode(EmitHint.Unspecified, typeNode, /*sourceFile*/ sourceFile, writer);
         const result = writer.getText();
@@ -9640,7 +9638,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 typePredicate.kind === TypePredicateKind.Identifier || typePredicate.kind === TypePredicateKind.AssertsIdentifier ? factory.createIdentifier(typePredicate.parameterName) : factory.createThisTypeNode(),
                 typePredicate.type && nodeBuilder.typeToTypeNode(typePredicate.type, enclosingDeclaration, toNodeBuilderFlags(flags) | NodeBuilderFlags.IgnoreErrors | NodeBuilderFlags.WriteTypeParametersInQualifiedName)! // TODO: GH#18217
             );
-            const printer = createPrinterWithRemoveComments();
+            const printer = createOrReusePrinter({ removeComments: true });
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, predicate, /*sourceFile*/ sourceFile, writer);
             return writer;
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index e81f2b090a8ae..289383c99c954 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1343,17 +1343,29 @@ const enum PipelinePhase {
     Emit,
 }
 
-/** @internal */
-export const createPrinterWithDefaults = memoize(() => createPrinter({}));
+const printerCache = new Map<string, Printer>();
 
+// If updating this, make sure the cache key is updated too.
 /** @internal */
-export const createPrinterWithRemoveComments = memoize(() => createPrinter({ removeComments: true }));
+export type ReusablePrinterOptions = Pick<PrinterOptions, "removeComments" | "neverAsciiEscape" | "omitTrailingSemicolon" | "module" | "target" | "newLine">;
 
 /** @internal */
-export const createPrinterWithRemoveCommentsNeverAsciiEscape = memoize(() => createPrinter({ removeComments: true, neverAsciiEscape: true }));
+export function createOrReusePrinter(o: ReusablePrinterOptions = {}) {
+    const key = `${keyBool(o.removeComments)}|${keyBool(o.neverAsciiEscape)}|${keyBool(o.omitTrailingSemicolon)}|${keyNum(o.module)}|${keyNum(o.target)}|${keyNum(o.newLine)}`;
+    let printer = printerCache.get(key);
+    if (!printer) {
+        printerCache.set(key, printer = createPrinter(o));
+    }
+    return printer;
 
-/** @internal */
-export const createPrinterWithRemoveCommentsOmitTrailingSemicolon = memoize(() => createPrinter({ removeComments: true, omitTrailingSemicolon: true }));
+    function keyBool(value: boolean | undefined) {
+        return value === undefined ? "u" : value ? 1 : 0;
+    }
+
+    function keyNum(value: number | undefined) {
+        return value === undefined ? "u" : `${value}`;
+    }
+}
 
 export function createPrinter(printerOptions: PrinterOptions = {}, handlers: PrintHandlers = {}): Printer {
     const {
diff --git a/src/services/callHierarchy.ts b/src/services/callHierarchy.ts
index a2d32e6da717f..fafa979780fbf 100644
--- a/src/services/callHierarchy.ts
+++ b/src/services/callHierarchy.ts
@@ -14,7 +14,7 @@ import {
     ClassLikeDeclaration,
     ClassStaticBlockDeclaration,
     compareStringsCaseSensitive,
-    createPrinterWithRemoveCommentsOmitTrailingSemicolon,
+    createOrReusePrinter,
     createTextRangeFromNode,
     createTextSpanFromBounds,
     createTextSpanFromRange,
@@ -245,7 +245,7 @@ function getCallHierarchyItemName(program: Program, node: CallHierarchyDeclarati
     }
     if (text === undefined) {
         // get the text from printing the node on a single line without comments...
-        const printer = createPrinterWithRemoveCommentsOmitTrailingSemicolon();
+        const printer = createOrReusePrinter({ removeComments: true, omitTrailingSemicolon: true });
         text = usingSingleLineStringWriter(writer => printer.writeNode(EmitHint.Unspecified, node, node.getSourceFile(), writer));
     }
     return { text, pos: declName.getStart(), end: declName.getEnd() };
diff --git a/src/services/completions.ts b/src/services/completions.ts
index 4193e651a037f..b538e0566ef62 100644
--- a/src/services/completions.ts
+++ b/src/services/completions.ts
@@ -34,6 +34,7 @@ import {
     ConstructorDeclaration,
     ContextFlags,
     createModuleSpecifierResolutionHost,
+    createOrReusePrinter,
     createPackageJsonImportFilter,
     createPrinter,
     createSortedArray,
@@ -1747,7 +1748,7 @@ function getEntryForObjectLiteralMethodCompletion(
         insertText = printer.printSnippetList(ListFormat.CommaDelimited | ListFormat.AllowTrailingComma, factory.createNodeArray([method], /*hasTrailingComma*/ true), sourceFile);
     }
 
-    const signaturePrinter = createPrinter({
+    const signaturePrinter = createOrReusePrinter({
         removeComments: true,
         module: options.module,
         target: options.target,
diff --git a/src/services/inlayHints.ts b/src/services/inlayHints.ts
index 49b113e927554..5f8d9ab7810af 100644
--- a/src/services/inlayHints.ts
+++ b/src/services/inlayHints.ts
@@ -2,7 +2,7 @@ import {
     __String,
     ArrowFunction,
     CallExpression,
-    createPrinterWithRemoveComments,
+    createOrReusePrinter,
     Debug,
     EmitHint,
     EnumMember,
@@ -382,7 +382,7 @@ export function provideInlayHints(context: InlayHintsContext): InlayHint[] {
 
     function printTypeInSingleLine(type: Type) {
         const flags = NodeBuilderFlags.IgnoreErrors | TypeFormatFlags.AllowUniqueESSymbolType | TypeFormatFlags.UseAliasDefinedOutsideCurrentScope;
-        const printer = createPrinterWithRemoveComments();
+        const printer = createOrReusePrinter({ removeComments: true });
 
         return usingSingleLineStringWriter(writer => {
             const typeNode = checker.typeToTypeNode(type, /*enclosingDeclaration*/ undefined, flags);
diff --git a/src/services/signatureHelp.ts b/src/services/signatureHelp.ts
index c8923140c4935..745756503ce21 100644
--- a/src/services/signatureHelp.ts
+++ b/src/services/signatureHelp.ts
@@ -7,7 +7,7 @@ import {
     CheckFlags,
     contains,
     countWhere,
-    createPrinterWithRemoveComments,
+    createOrReusePrinter,
     createTextSpan,
     createTextSpanFromBounds,
     createTextSpanFromNode,
@@ -659,7 +659,7 @@ function createTypeHelpItems(
 function getTypeHelpItem(symbol: Symbol, typeParameters: readonly TypeParameter[], checker: TypeChecker, enclosingDeclaration: Node, sourceFile: SourceFile): SignatureHelpItem {
     const typeSymbolDisplay = symbolToDisplayParts(checker, symbol);
 
-    const printer = createPrinterWithRemoveComments();
+    const printer = createOrReusePrinter({ removeComments: true });
     const parameters = typeParameters.map(t => createSignatureHelpParameterForTypeParameter(t, checker, enclosingDeclaration, sourceFile, printer));
 
     const documentation = symbol.getDocumentationComment(checker);
@@ -699,7 +699,7 @@ interface SignatureHelpItemInfo { readonly isVariadic: boolean; readonly paramet
 
 function itemInfoForTypeParameters(candidateSignature: Signature, checker: TypeChecker, enclosingDeclaration: Node, sourceFile: SourceFile): SignatureHelpItemInfo[] {
     const typeParameters = (candidateSignature.target || candidateSignature).typeParameters;
-    const printer = createPrinterWithRemoveComments();
+    const printer = createOrReusePrinter({ removeComments: true });
     const parameters = (typeParameters || emptyArray).map(t => createSignatureHelpParameterForTypeParameter(t, checker, enclosingDeclaration, sourceFile, printer));
     const thisParameter = candidateSignature.thisParameter ? [checker.symbolToParameterDeclaration(candidateSignature.thisParameter, enclosingDeclaration, signatureHelpNodeBuilderFlags)!] : [];
 
@@ -713,7 +713,7 @@ function itemInfoForTypeParameters(candidateSignature: Signature, checker: TypeC
 }
 
 function itemInfoForParameters(candidateSignature: Signature, checker: TypeChecker, enclosingDeclaration: Node, sourceFile: SourceFile): SignatureHelpItemInfo[] {
-    const printer = createPrinterWithRemoveComments();
+    const printer = createOrReusePrinter({ removeComments: true });
     const typeParameterParts = mapToDisplayParts(writer => {
         if (candidateSignature.typeParameters && candidateSignature.typeParameters.length) {
             const args = factory.createNodeArray(candidateSignature.typeParameters.map(p => checker.typeParameterToDeclaration(p, enclosingDeclaration, signatureHelpNodeBuilderFlags)!));
diff --git a/src/services/symbolDisplay.ts b/src/services/symbolDisplay.ts
index be2e83a48bb2f..a0a9059379d62 100644
--- a/src/services/symbolDisplay.ts
+++ b/src/services/symbolDisplay.ts
@@ -5,7 +5,7 @@ import {
     CallExpression,
     CheckFlags,
     contains,
-    createPrinterWithRemoveComments,
+    createOrReusePrinter,
     Debug,
     displayPart,
     EmitHint,
@@ -728,7 +728,7 @@ export function getSymbolDisplayPartsDocumentationAndSymbolKind(typeChecker: Typ
     return { displayParts, documentation, symbolKind, tags: tags.length === 0 ? undefined : tags };
 
     function getPrinter() {
-        return createPrinterWithRemoveComments();
+        return createOrReusePrinter({ removeComments: true });
     }
 
     function prefixNextMeaning() {
diff --git a/src/services/utilities.ts b/src/services/utilities.ts
index 9935d419b2c4b..1a53d38f9dfea 100644
--- a/src/services/utilities.ts
+++ b/src/services/utilities.ts
@@ -30,7 +30,7 @@ import {
     ConditionalExpression,
     contains,
     ContextFlags,
-    createPrinterWithRemoveCommentsOmitTrailingSemicolon,
+    createOrReusePrinter,
     createRange,
     createScanner,
     createTextSpan,
@@ -2984,7 +2984,7 @@ export function signatureToDisplayParts(typechecker: TypeChecker, signature: Sig
 export function nodeToDisplayParts(node: Node, enclosingDeclaration: Node): SymbolDisplayPart[] {
     const file = enclosingDeclaration.getSourceFile();
     return mapToDisplayParts(writer => {
-        const printer = createPrinterWithRemoveCommentsOmitTrailingSemicolon();
+        const printer = createOrReusePrinter({ removeComments: true, omitTrailingSemicolon: true });
         printer.writeNode(EmitHint.Unspecified, node, file, writer);
     });
 }

From 2f48ec3b575505fbd9634ed99e9fa28482ea2233 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Tue, 24 Jan 2023 13:04:32 -0800
Subject: [PATCH 8/9] messing around with printhelpers

---
 src/compiler/emitter.ts     | 97 +++++++++++++++++++++----------------
 src/compiler/types.ts       |  8 +--
 src/services/completions.ts | 11 ++---
 src/services/textChanges.ts |  6 +--
 4 files changed, 67 insertions(+), 55 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 289383c99c954..d9317f267b27c 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1347,11 +1347,11 @@ const printerCache = new Map<string, Printer>();
 
 // If updating this, make sure the cache key is updated too.
 /** @internal */
-export type ReusablePrinterOptions = Pick<PrinterOptions, "removeComments" | "neverAsciiEscape" | "omitTrailingSemicolon" | "module" | "target" | "newLine">;
+export type ReusablePrinterOptions = Pick<PrinterOptions, "removeComments" | "neverAsciiEscape" | "omitTrailingSemicolon" | "module" | "target" | "newLine" | "preserveSourceNewlines" | "terminateUnterminatedLiterals">;
 
 /** @internal */
 export function createOrReusePrinter(o: ReusablePrinterOptions = {}) {
-    const key = `${keyBool(o.removeComments)}|${keyBool(o.neverAsciiEscape)}|${keyBool(o.omitTrailingSemicolon)}|${keyNum(o.module)}|${keyNum(o.target)}|${keyNum(o.newLine)}`;
+    const key = `${keyBool(o.removeComments)}|${keyBool(o.neverAsciiEscape)}|${keyBool(o.omitTrailingSemicolon)}|${keyNum(o.module)}|${keyNum(o.target)}|${keyNum(o.newLine)}|${keyBool(o.preserveSourceNewlines)}|${keyBool(o.terminateUnterminatedLiterals)}`;
     let printer = printerCache.get(key);
     if (!printer) {
         printerCache.set(key, printer = createPrinter(o));
@@ -1368,18 +1368,19 @@ export function createOrReusePrinter(o: ReusablePrinterOptions = {}) {
 }
 
 export function createPrinter(printerOptions: PrinterOptions = {}, handlers: PrintHandlers = {}): Printer {
-    const {
-        hasGlobalName,
-        onEmitNode = noEmitNotification,
-        isEmitNotificationEnabled,
-        substituteNode = noEmitSubstitution,
-        onBeforeEmitNode,
-        onAfterEmitNode,
-        onBeforeEmitNodeArray,
-        onAfterEmitNodeArray,
-        onBeforeEmitToken,
-        onAfterEmitToken
-    } = handlers;
+    let theHandlers!: PrintHandlers & Required<Pick<PrintHandlers, "onEmitNode" | "substituteNode">>;
+
+    function setHandlers(newHandlers?: PrintHandlers) {
+        if (newHandlers) {
+            theHandlers = {
+                onEmitNode: noEmitNotification,
+                substituteNode: noEmitSubstitution,
+                ...newHandlers,
+            };
+        }
+    }
+
+    setHandlers(handlers);
 
     const extendedDiagnostics = !!printerOptions.extendedDiagnostics;
     const newLine = getNewLineCharacter(printerOptions);
@@ -1499,18 +1500,23 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
     /**
      * If `sourceFile` is `undefined`, `node` must be a synthesized `TypeNode`.
      */
-    function writeNode(hint: EmitHint, node: TypeNode, sourceFile: undefined, output: EmitTextWriter): void;
-    function writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile, output: EmitTextWriter): void;
-    function writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile | undefined, output: EmitTextWriter) {
+    function writeNode(hint: EmitHint, node: TypeNode, sourceFile: undefined, output: EmitTextWriter, handlers?: PrintHandlers): void;
+    function writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile, output: EmitTextWriter, handlers?: PrintHandlers): void;
+    function writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile | undefined, output: EmitTextWriter, handlers?: PrintHandlers) {
         const previousWriter = writer;
+        const previousHandlers = theHandlers;
+        setHandlers(handlers);
         setWriter(output, /*_sourceMapGenerator*/ undefined);
         print(hint, node, sourceFile);
         reset();
         writer = previousWriter;
+        theHandlers = previousHandlers;
     }
 
-    function writeList<T extends Node>(format: ListFormat, nodes: NodeArray<T>, sourceFile: SourceFile | undefined, output: EmitTextWriter) {
+    function writeList<T extends Node>(format: ListFormat, nodes: NodeArray<T>, sourceFile: SourceFile | undefined, output: EmitTextWriter, handlers?: PrintHandlers) {
         const previousWriter = writer;
+        const previousHandlers = theHandlers;
+        setHandlers(handlers);
         setWriter(output, /*_sourceMapGenerator*/ undefined);
         if (sourceFile) {
             setSourceFile(sourceFile);
@@ -1518,6 +1524,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         emitList(/*parentNode*/ undefined, nodes, format);
         reset();
         writer = previousWriter;
+        theHandlers = previousHandlers;
     }
 
     function getTextPosWithWriteLine() {
@@ -1566,9 +1573,11 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         return false;
     }
 
-    function writeBundle(bundle: Bundle, output: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined) {
+    function writeBundle(bundle: Bundle, output: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined, handlers?: PrintHandlers) {
         isOwnFileEmit = false;
         const previousWriter = writer;
+        const previousHandlers = theHandlers;
+        setHandlers(handlers);
         setWriter(output, sourceMapGenerator);
         emitShebangIfNeeded(bundle);
         emitPrologueDirectivesIfNeeded(bundle);
@@ -1623,6 +1632,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
 
         reset();
         writer = previousWriter;
+        theHandlers = previousHandlers;
     }
 
     function writeUnparsedSource(unparsed: UnparsedSource, output: EmitTextWriter) {
@@ -1633,15 +1643,18 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         writer = previousWriter;
     }
 
-    function writeFile(sourceFile: SourceFile, output: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined) {
+    function writeFile(sourceFile: SourceFile, output: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined, handlers?: PrintHandlers) {
         isOwnFileEmit = true;
         const previousWriter = writer;
+        const previousHandlers = theHandlers;
+        setHandlers(handlers);
         setWriter(output, sourceMapGenerator);
         emitShebangIfNeeded(sourceFile);
         emitPrologueDirectivesIfNeeded(sourceFile);
         print(EmitHint.SourceFile, sourceFile, sourceFile);
         reset();
         writer = previousWriter;
+        theHandlers = previousHandlers;
     }
 
     function beginPrint() {
@@ -1765,12 +1778,12 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
     function getPipelinePhase(phase: PipelinePhase, emitHint: EmitHint, node: Node) {
         switch (phase) {
             case PipelinePhase.Notification:
-                if (onEmitNode !== noEmitNotification && (!isEmitNotificationEnabled || isEmitNotificationEnabled(node))) {
+                if (theHandlers.onEmitNode !== noEmitNotification && (!theHandlers.isEmitNotificationEnabled || theHandlers.isEmitNotificationEnabled(node))) {
                     return pipelineEmitWithNotification;
                 }
                 // falls through
             case PipelinePhase.Substitution:
-                if (substituteNode !== noEmitSubstitution && (lastSubstitution = substituteNode(emitHint, node) || node) !== node) {
+                if (theHandlers.substituteNode !== noEmitSubstitution && (lastSubstitution = theHandlers.substituteNode(emitHint, node) || node) !== node) {
                     if (currentParenthesizerRule) {
                         lastSubstitution = currentParenthesizerRule(lastSubstitution);
                     }
@@ -1800,11 +1813,11 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
 
     function pipelineEmitWithNotification(hint: EmitHint, node: Node) {
         const pipelinePhase = getNextPipelinePhase(PipelinePhase.Notification, hint, node);
-        onEmitNode(hint, node, pipelinePhase);
+        theHandlers.onEmitNode(hint, node, pipelinePhase);
     }
 
     function pipelineEmitWithHint(hint: EmitHint, node: Node): void {
-        onBeforeEmitNode?.(node);
+        theHandlers.onBeforeEmitNode?.(node);
         if (preserveSourceNewlines) {
             const savedPreserveSourceNewlines = preserveSourceNewlines;
             beforeEmitNode(node);
@@ -1814,7 +1827,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
         else {
             pipelineEmitWithHintWorker(hint, node);
         }
-        onAfterEmitNode?.(node);
+        theHandlers.onAfterEmitNode?.(node);
         // clear the parenthesizer rule as we ascend
         currentParenthesizerRule = undefined;
     }
@@ -2185,8 +2198,8 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
             }
             if (isExpression(node)) {
                 hint = EmitHint.Expression;
-                if (substituteNode !== noEmitSubstitution) {
-                    const substitute = substituteNode(hint, node) || node;
+                if (theHandlers.substituteNode !== noEmitSubstitution) {
+                    const substitute = theHandlers.substituteNode(hint, node) || node;
                     if (substitute !== node) {
                         node = substitute;
                         if (currentParenthesizerRule) {
@@ -3227,7 +3240,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
                 state.declarationListContainerEndStack[state.stackIndex] = declarationListContainerEnd;
                 const emitComments = state.shouldEmitCommentsStack[state.stackIndex] = shouldEmitComments(node);
                 const emitSourceMaps = state.shouldEmitSourceMapsStack[state.stackIndex] = shouldEmitSourceMaps(node);
-                onBeforeEmitNode?.(node);
+                theHandlers.onBeforeEmitNode?.(node);
                 if (emitComments) emitCommentsBeforeNode(node);
                 if (emitSourceMaps) emitSourceMapsBeforeNode(node);
                 beforeEmitNode(node);
@@ -3279,7 +3292,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
                 afterEmitNode(savedPreserveSourceNewlines);
                 if (shouldEmitSourceMaps) emitSourceMapsAfterNode(node);
                 if (shouldEmitComments) emitCommentsAfterNode(node, savedContainerPos, savedContainerEnd, savedDeclarationListContainerEnd);
-                onAfterEmitNode?.(node);
+                theHandlers.onAfterEmitNode?.(node);
                 state.stackIndex--;
             }
         }
@@ -3780,7 +3793,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
     }
 
     function emitBlockFunctionBody(body: Block) {
-        onBeforeEmitNode?.(body);
+        theHandlers.onBeforeEmitNode?.(body);
         writeSpace();
         writePunctuation("{");
         increaseIndent();
@@ -3793,7 +3806,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
 
         decreaseIndent();
         writeToken(SyntaxKind.CloseBraceToken, body.statements.end, writePunctuation, body);
-        onAfterEmitNode?.(body);
+        theHandlers.onAfterEmitNode?.(body);
     }
 
     function emitBlockFunctionBodyOnSingleLine(body: Block) {
@@ -4761,7 +4774,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
                 return node.pos;
             }
 
-            onBeforeEmitNodeArray?.(modifiers);
+            theHandlers.onBeforeEmitNodeArray?.(modifiers);
 
             // partition modifiers into contiguous chunks of `Modifier` or `Decorator`
             let lastMode: "modifiers" | "decorators" | undefined;
@@ -4803,7 +4816,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
                 pos++;
             }
 
-            onAfterEmitNodeArray?.(modifiers);
+            theHandlers.onAfterEmitNodeArray?.(modifiers);
 
             if (lastModifier && !positionIsSynthesized(lastModifier.end)) {
                 return lastModifier.end;
@@ -4978,8 +4991,8 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
 
         const isEmpty = children === undefined || start >= children.length || count === 0;
         if (isEmpty && format & ListFormat.OptionalIfEmpty) {
-            onBeforeEmitNodeArray?.(children);
-            onAfterEmitNodeArray?.(children);
+            theHandlers.onBeforeEmitNodeArray?.(children);
+            theHandlers.onAfterEmitNodeArray?.(children);
             return;
         }
 
@@ -4990,7 +5003,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
             }
         }
 
-        onBeforeEmitNodeArray?.(children);
+        theHandlers.onBeforeEmitNodeArray?.(children);
 
         if (isEmpty) {
             // Write a line terminator if the parent node was multi-line
@@ -5005,7 +5018,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
             emitNodeListItems(emit, parentNode, children, format, parenthesizerRule, start, count, children.hasTrailingComma, children);
         }
 
-        onAfterEmitNodeArray?.(children);
+        theHandlers.onAfterEmitNodeArray?.(children);
 
         if (format & ListFormat.BracketsMask) {
             if (isEmpty && children) {
@@ -5231,12 +5244,12 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
     }
 
     function writeTokenNode(node: Node, writer: (s: string) => void) {
-        if (onBeforeEmitToken) {
-            onBeforeEmitToken(node);
+        if (theHandlers.onBeforeEmitToken) {
+            theHandlers.onBeforeEmitToken(node);
         }
         writer(tokenToString(node.kind)!);
-        if (onAfterEmitToken) {
-            onAfterEmitToken(node);
+        if (theHandlers.onAfterEmitToken) {
+            theHandlers.onAfterEmitToken(node);
         }
     }
 
@@ -5778,7 +5791,7 @@ export function createPrinter(printerOptions: PrinterOptions = {}, handlers: Pri
      * when `isfileLevelUniqueName` is passed as a callback to `makeUniqueName`.
      */
     function isFileLevelUniqueName(name: string, _isPrivate: boolean) {
-        return currentSourceFile ? ts.isFileLevelUniqueName(currentSourceFile, name, hasGlobalName) : true;
+        return currentSourceFile ? ts.isFileLevelUniqueName(currentSourceFile, name, theHandlers.hasGlobalName) : true;
     }
 
     /**
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 0a43afe978ea4..702969fc1183e 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -9160,10 +9160,10 @@ export interface Printer {
      * Prints a bundle of source files as-is, without any emit transformations.
      */
     printBundle(bundle: Bundle): string;
-    /** @internal */ writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile | undefined, writer: EmitTextWriter): void;
-    /** @internal */ writeList<T extends Node>(format: ListFormat, list: NodeArray<T> | undefined, sourceFile: SourceFile | undefined, writer: EmitTextWriter): void;
-    /** @internal */ writeFile(sourceFile: SourceFile, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined): void;
-    /** @internal */ writeBundle(bundle: Bundle, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined): void;
+    /** @internal */ writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile | undefined, writer: EmitTextWriter, handlers?: PrintHandlers): void;
+    /** @internal */ writeList<T extends Node>(format: ListFormat, list: NodeArray<T> | undefined, sourceFile: SourceFile | undefined, writer: EmitTextWriter, handlers?: PrintHandlers): void;
+    /** @internal */ writeFile(sourceFile: SourceFile, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined, handlers?: PrintHandlers): void;
+    /** @internal */ writeBundle(bundle: Bundle, writer: EmitTextWriter, sourceMapGenerator: SourceMapGenerator | undefined, handlers?: PrintHandlers): void;
     /** @deprecated @internal */ bundleFileInfo?: BundleFileInfo;
 }
 
diff --git a/src/services/completions.ts b/src/services/completions.ts
index b538e0566ef62..1c312a57dcd7f 100644
--- a/src/services/completions.ts
+++ b/src/services/completions.ts
@@ -36,7 +36,6 @@ import {
     createModuleSpecifierResolutionHost,
     createOrReusePrinter,
     createPackageJsonImportFilter,
-    createPrinter,
     createSortedArray,
     createTextRangeFromSpan,
     createTextSpanFromBounds,
@@ -292,7 +291,6 @@ import {
     positionBelongsToNode,
     positionIsASICandidate,
     positionsAreOnSameLine,
-    PrinterOptions,
     probablyUsesSemicolons,
     Program,
     programContainsModules,
@@ -308,6 +306,7 @@ import {
     rangeContainsPosition,
     rangeContainsPositionExclusive,
     rangeIsOnSingleLine,
+    ReusablePrinterOptions,
     ScriptElementKind,
     ScriptElementKindModifier,
     ScriptTarget,
@@ -1851,11 +1850,11 @@ function createObjectLiteralMethod(
 }
 
 function createSnippetPrinter(
-    printerOptions: PrinterOptions,
+    printerOptions: ReusablePrinterOptions,
 ) {
     let escapes: TextChange[] | undefined;
     const baseWriter = textChanges.createWriter(getNewLineCharacter(printerOptions));
-    const printer = createPrinter(printerOptions, baseWriter);
+    const printer = createOrReusePrinter(printerOptions);
     const writer: EmitTextWriter = {
         ...baseWriter,
         write: s => escapingWrite(s, () => baseWriter.write(s)),
@@ -1909,7 +1908,7 @@ function createSnippetPrinter(
     ): string {
         escapes = undefined;
         writer.clear();
-        printer.writeList(format, list, sourceFile, writer);
+        printer.writeList(format, list, sourceFile, writer, baseWriter);
         return writer.getText();
     }
 
@@ -1956,7 +1955,7 @@ function createSnippetPrinter(
     function printUnescapedNode(hint: EmitHint, node: Node, sourceFile: SourceFile): string {
         escapes = undefined;
         writer.clear();
-        printer.writeNode(hint, node, sourceFile, writer);
+        printer.writeNode(hint, node, sourceFile, writer, baseWriter);
         return writer.getText();
     }
 
diff --git a/src/services/textChanges.ts b/src/services/textChanges.ts
index 50621f641601d..d4fea865d443d 100644
--- a/src/services/textChanges.ts
+++ b/src/services/textChanges.ts
@@ -11,7 +11,7 @@ import {
     ConstructorDeclaration,
     contains,
     createNodeFactory,
-    createPrinter,
+    createOrReusePrinter,
     createRange,
     createSourceFile,
     createTextChange,
@@ -1301,12 +1301,12 @@ namespace changesToText {
     export function getNonformattedText(node: Node, sourceFile: SourceFile | undefined, newLineCharacter: string): { text: string, node: Node } {
         const writer = createWriter(newLineCharacter);
         const newLine = getNewLineKind(newLineCharacter);
-        createPrinter({
+        createOrReusePrinter({
             newLine,
             neverAsciiEscape: true,
             preserveSourceNewlines: true,
             terminateUnterminatedLiterals: true
-        }, writer).writeNode(EmitHint.Unspecified, node, sourceFile, writer);
+        }).writeNode(EmitHint.Unspecified, node, sourceFile, writer, writer);
         return { text: writer.getText(), node: assignPositionsToNode(node) };
     }
 }

From b1ed654a3870995e4e570e6b7ec03e5a74906a0a Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Tue, 24 Jan 2023 21:54:52 -0800
Subject: [PATCH 9/9] Restore previous formatting

---
 src/compiler/checker.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 32cf2fa054ef1..1aea0c180e432 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -6123,9 +6123,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         function symbolToStringWorker(writer: EmitTextWriter) {
             const entity = builder(symbol, meaning!, enclosingDeclaration, nodeFlags)!; // TODO: GH#18217
             // add neverAsciiEscape for GH#39027
-            const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile
-                ? createOrReusePrinter({ removeComments: true, neverAsciiEscape: true })
-                : createOrReusePrinter({ removeComments: true });
+            const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile ? createOrReusePrinter({ removeComments: true, neverAsciiEscape: true }) : createOrReusePrinter({ removeComments: true });
             const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
             printer.writeNode(EmitHint.Unspecified, entity, /*sourceFile*/ sourceFile, writer);
             return writer;