fix(48281) - Preserve indentation when adding missing properties

Author: MQuy

src/services/codefixes/fixAddMissingMember.ts

@@ -19,7 +19,7 @@ namespace ts.codefix {
         errorCodes,
         getCodeActions(context) {
             const typeChecker = context.program.getTypeChecker();
-            const info = getInfo(context.sourceFile, context.span.start, context.errorCode, typeChecker, context.program);
+            const info = getInfo(context.sourceFile, context.span.start, context.errorCode, typeChecker, context.program, context.formatContext);
             if (!info) {
                 return undefined;
             }
@@ -50,7 +50,7 @@ namespace ts.codefix {
 
             return createCombinedCodeActions(textChanges.ChangeTracker.with(context, changes => {
                 eachDiagnostic(context, errorCodes, diag => {
-                    const info = getInfo(diag.file, diag.start, diag.code, checker, context.program);
+                    const info = getInfo(diag.file, diag.start, diag.code, checker, context.program, context.formatContext);
                     if (!info || !addToSeen(seen, getNodeId(info.parentDeclaration) + "#" + info.token.text)) {
                         return;
                     }
@@ -141,6 +141,7 @@ namespace ts.codefix {
         readonly properties: Symbol[];
         readonly parentDeclaration: ObjectLiteralExpression;
         readonly indentation?: number;
+        readonly trimLeadingWhiteSpaces?: boolean;
     }
 
     interface JsxAttributesInfo {
@@ -150,7 +151,7 @@ namespace ts.codefix {
         readonly parentDeclaration: JsxOpeningLikeElement;
     }
 
-    function getInfo(sourceFile: SourceFile, tokenPos: number, errorCode: number, checker: TypeChecker, program: Program): Info | undefined {
+    function getInfo(sourceFile: SourceFile, tokenPos: number, errorCode: number, checker: TypeChecker, program: Program, formatContext: formatting.FormatContext): Info | undefined {
         // The identifier of the missing property. eg:
         // this.missing = 1;
         //      ^^^^^^^
@@ -171,7 +172,10 @@ namespace ts.codefix {
 
             const properties = arrayFrom(checker.getUnmatchedProperties(checker.getTypeAtLocation(parent), checker.getTypeAtLocation(param), /* requireOptionalProperties */ false, /* matchDiscriminantProperties */ false));
             if (!length(properties)) return undefined;
-            return { kind: InfoKind.ObjectLiteral, token: param.name, properties, indentation: 0, parentDeclaration: parent };
+
+            const formatOptions = getFormatCodeSettingsForWriting(formatContext, sourceFile);
+            const indentation = formatting.SmartIndenter.getIndentation(getLineStartPositionForPosition(tokenPos, sourceFile), sourceFile, formatOptions, getLineStartPositionForPosition(tokenPos, sourceFile) === tokenPos);
+            return { kind: InfoKind.ObjectLiteral, token: param.name, properties, indentation, trimLeadingWhiteSpaces: true, parentDeclaration: parent };
         }
 
         if (!isMemberName(token)) return undefined;
@@ -490,7 +494,8 @@ namespace ts.codefix {
         const options = {
             leadingTriviaOption: textChanges.LeadingTriviaOption.Exclude,
             trailingTriviaOption: textChanges.TrailingTriviaOption.Exclude,
-            indentation: info.indentation
+            indentation: info.indentation,
+            trimLeadingWhiteSpaces: info.trimLeadingWhiteSpaces,
         };
         changes.replaceNode(context.sourceFile, info.parentDeclaration, factory.createObjectLiteralExpression([...info.parentDeclaration.properties, ...props], /*multiLine*/ true), options);
     }

src/services/textChanges.ts

@@ -117,9 +117,9 @@ namespace ts.textChanges {
          */
         delta?: number;
         /**
-         * Do not trim leading white spaces in the edit range
+         * Trim leading white spaces in the edit range
          */
-        preserveLeadingWhitespace?: boolean;
+        trimLeadingWhiteSpaces?: boolean;
     }
 
     export interface ReplaceWithMultipleNodesOptions extends InsertNodeOptions {
@@ -492,7 +492,7 @@ namespace ts.textChanges {
             }
             const startPosition = getPrecedingNonSpaceCharacterPosition(sourceFile.text, fnStart - 1);
             const indent = sourceFile.text.slice(startPosition, fnStart);
-            this.insertNodeAt(sourceFile, fnStart, tag, { preserveLeadingWhitespace: false, suffix: this.newLineCharacter + indent });
+            this.insertNodeAt(sourceFile, fnStart, tag, { suffix: this.newLineCharacter + indent });
         }
 
         private createJSDocText(sourceFile: SourceFile, node: HasJSDoc) {
@@ -1068,7 +1068,7 @@ namespace ts.textChanges {
                 ? change.nodes.map(n => removeSuffix(format(n), newLineCharacter)).join(change.options?.joiner || newLineCharacter)
                 : format(change.node);
             // strip initial indentation (spaces or tabs) if text will be inserted in the middle of the line
-            const noIndent = (options.preserveLeadingWhitespace || options.indentation !== undefined || getLineStartPositionForPosition(pos, sourceFile) === pos) ? text : text.replace(/^\s+/, "");
+            const noIndent = (options.trimLeadingWhiteSpaces || (options.indentation === undefined && getLineStartPositionForPosition(pos, sourceFile) !== pos)) ? text.replace(/^\s+/, "") : text;
             return (options.prefix || "") + noIndent
                  + ((!options.suffix || endsWith(noIndent, options.suffix))
                     ? "" : options.suffix);

tests/cases/fourslash/codeFixAddMissingProperties_PreserveIndent.ts

@@ -0,0 +1,24 @@
+/// <reference path='fourslash.ts' />
+
+////interface Test {
+////    foo: string;
+////    bar(a: string): void;
+////}
+////function f (_spec: any) {}
+////function g (_spec: Test) {}
+////[|f(() => {
+////    g({});
+////});|]
+
+verify.codeFix({
+  index: 2,
+  description: ts.Diagnostics.Add_missing_properties.message,
+  newRangeContent:
+`f(() => {
+    g({
+        foo: "",
+        bar: function(a: string): void {
+            throw new Error("Function not implemented.");
+        }
+    });
+});`});