Progress

src/compiler/emitter.ts

@@ -842,6 +842,7 @@ namespace ts {
         let tempFlags: TempFlags; // TempFlags for the current name generation scope.
         let reservedNamesStack: Map<true>[]; // Stack of TempFlags reserved in enclosing name generation scopes.
         let reservedNames: Map<true>; // TempFlags to reserve in nested name generation scopes.
+        let preserveNewlines = printerOptions.preserveNewlines; // Can be overridden inside nodes with the `IgnoreSourceNewlines` emit flag.
 
         let writer: EmitTextWriter;
         let ownWriter: EmitTextWriter; // Reusable `EmitTextWriter` for basic printing.
@@ -1164,8 +1165,12 @@ namespace ts {
         function pipelineEmit(emitHint: EmitHint, node: Node) {
             const savedLastNode = lastNode;
             const savedLastSubstitution = lastSubstitution;
+            const savedPreserveNewlines = preserveNewlines;
             lastNode = node;
             lastSubstitution = undefined;
+            if (preserveNewlines && !!(getEmitFlags(node) & EmitFlags.IgnoreSourceNewlines)) {
+                preserveNewlines = false;
+            }
 
             const pipelinePhase = getPipelinePhase(PipelinePhase.Notification, emitHint, node);
             pipelinePhase(emitHint, node);
@@ -1175,6 +1180,7 @@ namespace ts {
             const substitute = lastSubstitution;
             lastNode = savedLastNode;
             lastSubstitution = savedLastSubstitution;
+            preserveNewlines = savedPreserveNewlines;
 
             return substitute || node;
         }
@@ -3991,7 +3997,7 @@ namespace ts {
 
             if (isEmpty) {
                 // Write a line terminator if the parent node was multi-line
-                if (format & ListFormat.MultiLine) {
+                if (format & ListFormat.MultiLine && !(preserveNewlines && rangeIsOnSingleLine(parentNode, currentSourceFile!))) {
                     writeLine();
                 }
                 else if (format & ListFormat.SpaceBetweenBraces && !(format & ListFormat.NoSpaceIfEmpty)) {
@@ -4262,7 +4268,7 @@ namespace ts {
         }
 
         function getLeadingLineTerminatorCount(parentNode: TextRange, children: NodeArray<Node>, format: ListFormat): number {
-            if (format & ListFormat.PreserveLines || printerOptions.preserveNewlines) {
+            if (format & ListFormat.PreserveLines || preserveNewlines) {
                 if (format & ListFormat.PreferNewLine) {
                     return 1;
                 }
@@ -4283,7 +4289,7 @@ namespace ts {
         }
 
         function getSeparatingLineTerminatorCount(previousNode: Node | undefined, nextNode: Node, format: ListFormat): number {
-            if (format & ListFormat.PreserveLines || printerOptions.preserveNewlines) {
+            if (format & ListFormat.PreserveLines || preserveNewlines) {
                 if (previousNode === undefined || nextNode === undefined) {
                     return 0;
                 }
@@ -4302,7 +4308,7 @@ namespace ts {
         }
 
         function getClosingLineTerminatorCount(parentNode: TextRange, children: NodeArray<Node>, format: ListFormat): number {
-            if (format & ListFormat.PreserveLines || printerOptions.preserveNewlines) {
+            if (format & ListFormat.PreserveLines || preserveNewlines) {
                 if (format & ListFormat.PreferNewLine) {
                     return 1;
                 }

src/compiler/factoryPublic.ts

@@ -3559,6 +3559,11 @@ namespace ts {
         return node;
     }
 
+    export function ignoreSourceNewlines<T extends Node>(node: T): T {
+        getOrCreateEmitNode(node).flags |= EmitFlags.IgnoreSourceNewlines;
+        return node;
+    }
+
     /**
      * Gets the constant value to emit for an expression.
      */

src/compiler/types.ts

@@ -5780,6 +5780,7 @@ namespace ts {
         NoAsciiEscaping = 1 << 24,              // When synthesizing nodes that lack an original node or textSourceNode, we want to write the text on the node with ASCII escaping substitutions.
         /*@internal*/ TypeScriptClassWrapper = 1 << 25, // The node is an IIFE class wrapper created by the ts transform.
         /*@internal*/ NeverApplyImportHelper = 1 << 26, // Indicates the node should never be wrapped with an import star helper (because, for example, it imports tslib itself)
+        /*@internal*/ IgnoreSourceNewlines = 1 << 27,   // Overrides `printerOptions.preserveNewlines` to print this node (and all descendants) with default whitespace.
     }
 
     export interface EmitHelper {

src/services/formatting/formatting.ts

@@ -70,7 +70,7 @@ namespace ts.formatting {
          * Formatter calls this function when rule adds or deletes new lines from the text
          * so indentation scope can adjust values of indentation and delta.
          */
-        recomputeIndentation(lineAddedByFormatting: boolean): void;
+        recomputeIndentation(lineAddedByFormatting: boolean, parent: Node): void;
     }
 
     export function formatOnEnter(position: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[] {
@@ -565,8 +565,9 @@ namespace ts.formatting {
                     !suppressDelta && shouldAddDelta(line, kind, container) ? indentation + getDelta(container) : indentation,
                 getIndentation: () => indentation,
                 getDelta,
-                recomputeIndentation: lineAdded => {
-                    if (node.parent && SmartIndenter.shouldIndentChildNode(options, node.parent, node, sourceFile)) {
+                recomputeIndentation: (lineAdded, parentIn) => {
+                    const parent = node.parent || parentIn;
+                    if (node !== parent && SmartIndenter.shouldIndentChildNode(options, parent, node, sourceFile)) {
                         indentation += lineAdded ? options.indentSize! : -options.indentSize!;
                         delta = SmartIndenter.shouldIndentChildNode(options, node) ? options.indentSize! : 0;
                     }
@@ -991,7 +992,7 @@ namespace ts.formatting {
                             // Handle the case where the next line is moved to be the end of this line.
                             // In this case we don't indent the next line in the next pass.
                             if (currentParent.getStart(sourceFile) === currentItem.pos) {
-                                dynamicIndentation.recomputeIndentation(/*lineAddedByFormatting*/ false);
+                                dynamicIndentation.recomputeIndentation(/*lineAddedByFormatting*/ false, currentParent);
                             }
                             break;
                         case LineAction.LineAdded:
@@ -999,7 +1000,7 @@ namespace ts.formatting {
                             // In this case we indent token2 in the next pass but we set
                             // sameLineIndent flag to notify the indenter that the indentation is within the line.
                             if (currentParent.getStart(sourceFile) === currentItem.pos) {
-                                dynamicIndentation.recomputeIndentation(/*lineAddedByFormatting*/ true);
+                                dynamicIndentation.recomputeIndentation(/*lineAddedByFormatting*/ true, currentParent);
                             }
                             break;
                         default:

src/services/refactors/extractType.ts

@@ -159,7 +159,7 @@ namespace ts.refactor {
             typeParameters.map(id => updateTypeParameterDeclaration(id, id.name, id.constraint, /* defaultType */ undefined)),
             selection
         );
-        changes.insertNodeBefore(file, firstStatement, newTypeNode, /* blankLineBetween */ true);
+        changes.insertNodeBefore(file, firstStatement, ignoreSourceNewlines(newTypeNode), /* blankLineBetween */ true);
         changes.replaceNode(file, selection, createTypeReferenceNode(name, typeParameters.map(id => createTypeReferenceNode(id.name, /* typeArguments */ undefined))));
     }
 
@@ -174,7 +174,7 @@ namespace ts.refactor {
             /* heritageClauses */ undefined,
             typeElements
         );
-        changes.insertNodeBefore(file, firstStatement, newTypeNode, /* blankLineBetween */ true);
+        changes.insertNodeBefore(file, firstStatement, ignoreSourceNewlines(newTypeNode), /* blankLineBetween */ true);
         changes.replaceNode(file, selection, createTypeReferenceNode(name, typeParameters.map(id => createTypeReferenceNode(id.name, /* typeArguments */ undefined))));
     }
 

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -4359,6 +4359,7 @@ declare namespace ts {
     function setSyntheticTrailingComments<T extends Node>(node: T, comments: SynthesizedComment[] | undefined): T;
     function addSyntheticTrailingComment<T extends Node>(node: T, kind: SyntaxKind.SingleLineCommentTrivia | SyntaxKind.MultiLineCommentTrivia, text: string, hasTrailingNewLine?: boolean): T;
     function moveSyntheticComments<T extends Node>(node: T, original: Node): T;
+    function ignoreSourceNewlines<T extends Node>(node: T): T;
     /**
      * Gets the constant value to emit for an expression.
      */

tests/baselines/reference/api/typescript.d.ts

@@ -4359,6 +4359,7 @@ declare namespace ts {
     function setSyntheticTrailingComments<T extends Node>(node: T, comments: SynthesizedComment[] | undefined): T;
     function addSyntheticTrailingComment<T extends Node>(node: T, kind: SyntaxKind.SingleLineCommentTrivia | SyntaxKind.MultiLineCommentTrivia, text: string, hasTrailingNewLine?: boolean): T;
     function moveSyntheticComments<T extends Node>(node: T, original: Node): T;
+    function ignoreSourceNewlines<T extends Node>(node: T): T;
     /**
      * Gets the constant value to emit for an expression.
      */

tests/baselines/reference/objectLiteralShorthandPropertiesErrorFromNotUsingIdentifier.js

@@ -35,7 +35,8 @@ var y = {
     "typeof": 
 };
 var x = (_a = {
-        a: a, : .b,
+        a: a,
+        : .b,
         a: a
     },
     _a["ss"] = ,

tests/baselines/reference/objectLiteralShorthandPropertiesErrorWithModule.js

@@ -25,7 +25,8 @@ var n;
 (function (n) {
     var z = 10000;
     n.y = {
-        m: m, : .x // error
+        m: m,
+        : .x // error
     };
 })(n || (n = {}));
 m.y.x;

tests/baselines/reference/objectTypesWithOptionalProperties2.js

@@ -42,5 +42,6 @@ var C2 = /** @class */ (function () {
     return C2;
 }());
 var b = {
-    x: function () { }, 1:  // error
+    x: function () { },
+    1:  // error
 };

tests/baselines/reference/parserErrorRecovery_ObjectLiteral2.js

@@ -3,5 +3,4 @@ var v = { a
 return;
 
 //// [parserErrorRecovery_ObjectLiteral2.js]
-var v = { a: a,
-    "return":  };
+var v = { a: a, "return":  };

tests/cases/fourslash/extract-const-callback-function-this3.ts

@@ -10,8 +10,6 @@ edit.applyRefactor({
     actionDescription: "Extract to constant in enclosing scope",
     newContent:
 `declare function fWithThis(fn: (this: { a: string }, a: string) => string): void;
-const newLocal = function(this: {
-    a: string;
-}, a: string): string { return this.a; };
+const newLocal = function(this: { a: string; }, a: string): string { return this.a; };
 fWithThis(/*RENAME*/newLocal);`
 });

tests/cases/fourslash/moveToNewFile_declarationKinds.ts

@@ -24,16 +24,11 @@ type U = T; type V = I;`,
         "/x.ts":
 `export const x = 0;
 export function f() { }
-export class C {
-}
-export enum E {
-}
-export namespace N {
-    export const x = 0;
-}
+export class C { }
+export enum E { }
+export namespace N { export const x = 0; }
 export type T = number;
-export interface I {
-}
+export interface I { }
 `,
     },
 });

tests/cases/fourslash/refactorConvertToEs6Module_export_object.ts

@@ -22,6 +22,5 @@ verify.codeFix({
 export function f() { }
 export function g() { }
 export function h() { }
-export class C {
-}`,
+export class C { }`,
 });

tests/cases/fourslash/refactorConvertToEs6Module_expressionToDeclaration.ts

@@ -15,8 +15,6 @@ verify.codeFix({
 `var C = {};
 console.log(C);
 export async function* f(p) { p; }
-const _C = class C extends D {
-    m() { }
-};
+const _C = class C extends D { m() { } };
 export { _C as C };`,
 });