Merge pull request microsoft#19578 from amcasey/GH19395

Don't pass synthesized node to typeToTypeNode

Author: amcasey

src/compiler/checker.ts

@@ -2444,18 +2444,21 @@ namespace ts {
         function createNodeBuilder() {
             return {
                 typeToTypeNode: (type: Type, enclosingDeclaration?: Node, flags?: NodeBuilderFlags) => {
+                    Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & NodeFlags.Synthesized) === 0);
                     const context = createNodeBuilderContext(enclosingDeclaration, flags);
                     const resultingNode = typeToTypeNodeHelper(type, context);
                     const result = context.encounteredError ? undefined : resultingNode;
                     return result;
                 },
                 indexInfoToIndexSignatureDeclaration: (indexInfo: IndexInfo, kind: IndexKind, enclosingDeclaration?: Node, flags?: NodeBuilderFlags) => {
+                    Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & NodeFlags.Synthesized) === 0);
                     const context = createNodeBuilderContext(enclosingDeclaration, flags);
                     const resultingNode = indexInfoToIndexSignatureDeclarationHelper(indexInfo, kind, context);
                     const result = context.encounteredError ? undefined : resultingNode;
                     return result;
                 },
                 signatureToSignatureDeclaration: (signature: Signature, kind: SyntaxKind, enclosingDeclaration?: Node, flags?: NodeBuilderFlags) => {
+                    Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & NodeFlags.Synthesized) === 0);
                     const context = createNodeBuilderContext(enclosingDeclaration, flags);
                     const resultingNode = signatureToSignatureDeclarationHelper(signature, kind, context);
                     const result = context.encounteredError ? undefined : resultingNode;

src/services/refactors/extractSymbol.ts

@@ -730,7 +730,7 @@ namespace ts.refactor.extractSymbol {
                 let type = checker.getTypeOfSymbolAtLocation(usage.symbol, usage.node);
                 // Widen the type so we don't emit nonsense annotations like "function fn(x: 3) {"
                 type = checker.getBaseTypeOfLiteralType(type);
-                typeNode = checker.typeToTypeNode(type, node, NodeBuilderFlags.NoTruncation);
+                typeNode = checker.typeToTypeNode(type, scope, NodeBuilderFlags.NoTruncation);
             }
 
             const paramDecl = createParameter(

tests/cases/fourslash/extract-method27.ts

@@ -0,0 +1,34 @@
+/// <reference path='fourslash.ts' />
+
+// Repro https://github.com/Microsoft/TypeScript/issues/19395
+
+// @Filename: test.ts
+//// export const b = 2;
+//// interface Interface { }
+////
+//// async function handle(i: Interface) {
+////     /*a*/const x = 3, y = i;/*b*/
+//// }
+// @Filename: library.d.ts
+//// export as namespace NS;
+//// export const a = 1;
+
+
+goTo.select('a', 'b')
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in module scope",
+    newContent:
+`export const b = 2;
+interface Interface { }
+
+async function handle(i: Interface) {
+    /*RENAME*/newFunction(i);
+}
+
+function newFunction(i: Interface) {
+    const x = 3, y = i;
+}
+`
+});