optimization, reduce memory usage

remove the creation of unnecessary lambda wrappers.
Speeds up 11% the project initialization time of tsserver in large repositories.

Author: VincentBailly

src/compiler/program.ts

@@ -978,7 +978,7 @@ function getEmitSyntaxForUsageLocationWorker(file: Pick<SourceFile, "fileName" |
     const fileEmitMode = getEmitModuleFormatOfFileWorker(file, compilerOptions);
     return fileEmitMode === ModuleKind.CommonJS ? ModuleKind.CommonJS :
         emitModuleKindIsNonNodeESM(fileEmitMode) || fileEmitMode === ModuleKind.Preserve ? ModuleKind.ESNext :
-        undefined;
+            undefined;
 }
 
 /** @internal */
@@ -1353,8 +1353,8 @@ export function getImpliedNodeFormatForFileWorker(
         || pathContainsNodeModules(fileName);
     return fileExtensionIsOneOf(fileName, [Extension.Dmts, Extension.Mts, Extension.Mjs]) ? ModuleKind.ESNext :
         fileExtensionIsOneOf(fileName, [Extension.Dcts, Extension.Cts, Extension.Cjs]) ? ModuleKind.CommonJS :
-        shouldLookupFromPackageJson && fileExtensionIsOneOf(fileName, [Extension.Dts, Extension.Ts, Extension.Tsx, Extension.Js, Extension.Jsx]) ? lookupFromPackageJson() :
-        undefined; // other extensions, like `json` or `tsbuildinfo`, are set as `undefined` here but they should never be fed through the transformer pipeline
+            shouldLookupFromPackageJson && fileExtensionIsOneOf(fileName, [Extension.Dts, Extension.Ts, Extension.Tsx, Extension.Js, Extension.Jsx]) ? lookupFromPackageJson() :
+                undefined; // other extensions, like `json` or `tsbuildinfo`, are set as `undefined` here but they should never be fed through the transformer pipeline
 
     function lookupFromPackageJson(): Partial<CreateSourceFileOptions> {
         const state = getTemporaryModuleResolutionState(packageJsonInfoCache, host, options);
@@ -2276,8 +2276,8 @@ export function createProgram(_rootNamesOrOptions: readonly string[] | CreatePro
                                     Diagnostics.Reusing_resolution_of_module_0_from_1_of_old_program_it_was_successfully_resolved_to_2_with_Package_ID_3 :
                                     Diagnostics.Reusing_resolution_of_module_0_from_1_of_old_program_it_was_successfully_resolved_to_2 :
                                 oldResolved.packageId ?
-                                Diagnostics.Reusing_resolution_of_type_reference_directive_0_from_1_of_old_program_it_was_successfully_resolved_to_2_with_Package_ID_3 :
-                                Diagnostics.Reusing_resolution_of_type_reference_directive_0_from_1_of_old_program_it_was_successfully_resolved_to_2,
+                                    Diagnostics.Reusing_resolution_of_type_reference_directive_0_from_1_of_old_program_it_was_successfully_resolved_to_2_with_Package_ID_3 :
+                                    Diagnostics.Reusing_resolution_of_type_reference_directive_0_from_1_of_old_program_it_was_successfully_resolved_to_2,
                             name,
                             containingSourceFile ? getNormalizedAbsolutePath(containingSourceFile.originalFileName, currentDirectory) : containingFile,
                             oldResolved.resolvedFileName,
@@ -4986,8 +4986,8 @@ function updateHostForUseSourceOfProjectReferenceRedirect(host: HostForUseSource
 
     function fileOrDirectoryExistsUsingSource(fileOrDirectory: string, isFile: boolean): boolean {
         const fileOrDirectoryExistsUsingSource = isFile ?
-            (file: string) => fileExistsIfProjectReferenceDts(file) :
-            (dir: string) => directoryExistsIfProjectReferenceDeclDir(dir);
+            fileExistsIfProjectReferenceDts :
+            directoryExistsIfProjectReferenceDeclDir;
         // Check current directory or file
         const result = fileOrDirectoryExistsUsingSource(fileOrDirectory);
         if (result !== undefined) return result;