Revert to using spread instead of mutating value later

src/harness/client.ts

@@ -396,11 +396,14 @@ namespace ts.server {
             for (const entry of body.locs) {
                 const fileName = entry.file;
                 for (const { start, end, declarationStart, declarationEnd, ...prefixSuffixText } of entry.locs) {
-                    const renameLocation: RenameLocation = { textSpan: this.decodeSpan({ start, end }, fileName), fileName, ...prefixSuffixText };
-                    if (declarationStart !== undefined) {
-                        renameLocation.declarationSpan = this.decodeSpan({ start: declarationStart, end: declarationEnd! }, fileName);
-                    }
-                    locations.push(renameLocation);
+                    locations.push({
+                        textSpan: this.decodeSpan({ start, end }, fileName),
+                        fileName,
+                        ...(declarationStart !== undefined ?
+                            { declarationSpan: this.decodeSpan({ start: declarationStart, end: declarationEnd! }, fileName) } :
+                            undefined),
+                        ...prefixSuffixText
+                    });
                 }
             }
 

src/harness/fourslash.ts

@@ -957,17 +957,16 @@ namespace FourSlash {
                 definition: typeof definition === "string" ? definition : { ...definition, range: ts.createTextSpanFromRange(definition.range) },
                 references: ranges.map<ts.ReferenceEntry>(r => {
                     const { isWriteAccess = false, isDefinition = false, isInString, declarationRangeIndex } = (r.marker && r.marker.data || {}) as { isWriteAccess?: boolean, isDefinition?: boolean, isInString?: true, declarationRangeIndex?: number };
-                    const result: ts.ReferenceEntry = {
+                    return {
                         fileName: r.fileName,
                         textSpan: ts.createTextSpanFromRange(r),
                         isWriteAccess,
                         isDefinition,
+                        ...(declarationRangeIndex !== undefined ?
+                            { declarationSpan: ts.createTextSpanFromRange(this.getRanges()[declarationRangeIndex]) } :
+                            undefined),
                         ...(isInString ? { isInString: true } : undefined),
                     };
-                    if (declarationRangeIndex !== undefined) {
-                        result.declarationSpan = ts.createTextSpanFromRange(this.getRanges()[declarationRangeIndex]);
-                    }
-                    return result;
                 }),
             }));
 
@@ -1192,14 +1191,17 @@ Actual: ${stringify(fullActual)}`);
 
                 const sort = (locations: ReadonlyArray<ts.RenameLocation> | undefined) =>
                     locations && ts.sort(locations, (r1, r2) => ts.compareStringsCaseSensitive(r1.fileName, r2.fileName) || r1.textSpan.start - r2.textSpan.start);
-                assert.deepEqual(sort(references), sort(ranges.map(rangeOrOptions => {
+                assert.deepEqual(sort(references), sort(ranges.map((rangeOrOptions): ts.RenameLocation => {
                     const { range, ...prefixSuffixText } = "range" in rangeOrOptions ? rangeOrOptions : { range: rangeOrOptions };
-                    const result: ts.RenameLocation = { fileName: range.fileName, textSpan: ts.createTextSpanFromRange(range), ...prefixSuffixText };
                     const { declarationRangeIndex } = (range.marker && range.marker.data || {}) as { declarationRangeIndex?: number; };
-                    if (declarationRangeIndex !== undefined) {
-                        result.declarationSpan = ts.createTextSpanFromRange(this.getRanges()[declarationRangeIndex]);
-                    }
-                    return result;
+                    return {
+                        fileName: range.fileName,
+                        textSpan: ts.createTextSpanFromRange(range),
+                        ...(declarationRangeIndex !== undefined ?
+                            { declarationSpan: ts.createTextSpanFromRange(this.getRanges()[declarationRangeIndex]) } :
+                            undefined),
+                        ...prefixSuffixText
+                    };
                 })));
             }
         }

src/server/session.ts

@@ -1066,14 +1066,11 @@ namespace ts.server {
         }
 
         private toDeclarationFileSpan(fileName: string, textSpan: TextSpan, declarationSpan: TextSpan | undefined, project: Project): protocol.DeclarationFileSpan {
-            const result = this.toFileSpan(fileName, textSpan, project) as protocol.DeclarationFileSpan;
-            if (declarationSpan) {
-                const declaration = this.toFileSpan(fileName, declarationSpan, project);
-                result.declarationStart = declaration.start;
-                result.declarationEnd = declaration.end;
-            }
-            return result;
-
+            const fileSpan = this.toFileSpan(fileName, textSpan, project);
+            const declaration = declarationSpan && this.toFileSpan(fileName, declarationSpan, project);
+            return declaration ?
+                { ...fileSpan, declarationStart: declaration.start, declarationEnd: declaration.end } :
+                fileSpan;
         }
 
         private getTypeDefinition(args: protocol.FileLocationRequestArgs): ReadonlyArray<protocol.DeclarationFileSpan> {
@@ -1099,36 +1096,27 @@ namespace ts.server {
             const { file, project } = this.getFileAndProject(args);
             const position = this.getPositionInFile(args, file);
             const implementations = this.mapImplementationLocations(project.getLanguageService().getImplementationAtPosition(file, position) || emptyArray, project);
-            if (simplifiedResult) {
-                return implementations.map(({ fileName, textSpan, declarationSpan }) => this.toDeclarationFileSpan(fileName, textSpan, declarationSpan, project));
-            }
-
-            return implementations.map(Session.mapToOriginalLocation);
+            return simplifiedResult ?
+                implementations.map(({ fileName, textSpan, declarationSpan }) => this.toDeclarationFileSpan(fileName, textSpan, declarationSpan, project)) :
+                implementations.map(Session.mapToOriginalLocation);
         }
 
         private getOccurrences(args: protocol.FileLocationRequestArgs): ReadonlyArray<protocol.OccurrencesResponseItem> {
             const { file, project } = this.getFileAndProject(args);
-
             const position = this.getPositionInFile(args, file);
-
             const occurrences = project.getLanguageService().getOccurrencesAtPosition(file, position);
-
-            if (!occurrences) {
-                return emptyArray;
-            }
-
-            return occurrences.map(occurrence => {
-                const { fileName, isWriteAccess, textSpan, isInString, declarationSpan } = occurrence;
-                const scriptInfo = project.getScriptInfo(fileName)!;
-                const result = toProtocolDeclarationTextSpan(textSpan, declarationSpan, scriptInfo) as protocol.OccurrencesResponseItem;
-                result.file = fileName;
-                result.isWriteAccess = isWriteAccess;
-                // no need to serialize the property if it is not true
-                if (isInString) {
-                    result.isInString = isInString;
-                }
-                return result;
-            });
+            return occurrences ?
+                occurrences.map<protocol.OccurrencesResponseItem>(occurrence => {
+                    const { fileName, isWriteAccess, textSpan, isInString, declarationSpan } = occurrence;
+                    const scriptInfo = project.getScriptInfo(fileName)!;
+                    return {
+                        ...toProtocolDeclarationTextSpan(textSpan, declarationSpan, scriptInfo),
+                        file: fileName,
+                        isWriteAccess,
+                        ...(isInString ? { isInString } : undefined)
+                    };
+                }) :
+                emptyArray;
         }
 
         private getSyntacticDiagnosticsSync(args: protocol.SyntacticDiagnosticsSyncRequestArgs): ReadonlyArray<protocol.Diagnostic> | ReadonlyArray<protocol.DiagnosticWithLinePosition> {
@@ -1178,11 +1166,10 @@ namespace ts.server {
                 const scriptInfo = project.getScriptInfo(fileName)!;
                 return {
                     file: fileName,
-                    highlightSpans: highlightSpans.map(({ textSpan, kind, declarationSpan }) => {
-                        const result = toProtocolDeclarationTextSpan(textSpan, declarationSpan, scriptInfo) as protocol.HighlightSpan;
-                        result.kind = kind;
-                        return result;
-                    })
+                    highlightSpans: highlightSpans.map(({ textSpan, kind, declarationSpan }) => ({
+                        ...toProtocolDeclarationTextSpan(textSpan, declarationSpan, scriptInfo),
+                        kind
+                    }))
                 };
             });
         }
@@ -1328,8 +1315,7 @@ namespace ts.server {
                         isDefinition
                     };
                 }));
-            const result: protocol.ReferencesResponseBody = { refs, symbolName, symbolStartOffset, symbolDisplayString };
-            return result;
+            return { refs, symbolName, symbolStartOffset, symbolDisplayString };
         }
         /**
          * @param fileName is the name of the file to be opened
@@ -2580,11 +2566,11 @@ namespace ts.server {
     }
 
     function toProtocolDeclarationTextSpan(span: TextSpan, declarationSpan: TextSpan | undefined, scriptInfo: ScriptInfo): protocol.DeclarationTextSpan {
-        const result = toProcolTextSpan(span, scriptInfo) as protocol.DeclarationTextSpan;
-        if (!declarationSpan) return result;
-        result.declarationStart = scriptInfo.positionToLineOffset(declarationSpan.start);
-        result.declarationEnd = scriptInfo.positionToLineOffset(textSpanEnd(declarationSpan));
-        return result;
+        const textSpan = toProcolTextSpan(span, scriptInfo);
+        const declarationTextSpan = declarationSpan && toProcolTextSpan(declarationSpan, scriptInfo);
+        return declarationTextSpan ?
+            { ...textSpan, declarationStart: declarationTextSpan.start, declarationEnd: declarationTextSpan.end } :
+            textSpan;
     }
 
     function convertTextChangeToCodeEdit(change: TextChange, scriptInfo: ScriptInfoOrConfig): protocol.CodeEdit {

src/services/findAllReferences.ts

@@ -161,15 +161,14 @@ namespace ts.FindAllReferences {
         }
     }
 
-    export function setDeclarationSpan(span: DocumentSpan, sourceFile: SourceFile, declaration?: DeclarationNode) {
-        if (declaration) {
-            const declarationSpan = isDeclarationNodeWithStartAndEnd(declaration) ?
-                getTextSpan(declaration.start, sourceFile, declaration.end) :
-                getTextSpan(declaration, sourceFile);
-            if (declarationSpan.start !== span.textSpan.start || declarationSpan.length !== span.textSpan.length) {
-                span.declarationSpan = declarationSpan;
-            }
-        }
+    export function toDeclarationSpan(textSpan: TextSpan, sourceFile: SourceFile, declaration?: DeclarationNode): { declarationSpan: TextSpan } | undefined {
+        if (!declaration) return undefined;
+        const declarationSpan = isDeclarationNodeWithStartAndEnd(declaration) ?
+            getTextSpan(declaration.start, sourceFile, declaration.end) :
+            getTextSpan(declaration, sourceFile);
+        return declarationSpan.start !== textSpan.start || declarationSpan.length !== textSpan.length ?
+            { declarationSpan } :
+            undefined;
     }
 
     export interface Options {
@@ -304,17 +303,17 @@ namespace ts.FindAllReferences {
 
         const { node, name, kind, displayParts, declaration } = info;
         const sourceFile = node.getSourceFile();
-        const result: ReferencedSymbolDefinitionInfo = {
+        const textSpan = getTextSpan(isComputedPropertyName(node) ? node.expression : node, sourceFile);
+        return {
             containerKind: ScriptElementKind.unknown,
             containerName: "",
             fileName: sourceFile.fileName,
             kind,
             name,
-            textSpan: getTextSpan(isComputedPropertyName(node) ? node.expression : node, sourceFile),
-            displayParts
+            textSpan,
+            displayParts,
+            ...toDeclarationSpan(textSpan, sourceFile, declaration)
         };
-        setDeclarationSpan(result, sourceFile, declaration);
-        return result;
     }
 
     function getDefinitionKindAndDisplayParts(symbol: Symbol, checker: TypeChecker, node: Node): { displayParts: SymbolDisplayPart[], kind: ScriptElementKind } {
@@ -351,9 +350,12 @@ namespace ts.FindAllReferences {
         }
         else {
             const sourceFile = entry.node.getSourceFile();
-            const result: DocumentSpan = { textSpan: getTextSpan(entry.node, sourceFile), fileName: sourceFile.fileName };
-            setDeclarationSpan(result, sourceFile, entry.declaration);
-            return result;
+            const textSpan = getTextSpan(entry.node, sourceFile);
+            return {
+                textSpan,
+                fileName: sourceFile.fileName,
+                ...toDeclarationSpan(textSpan, sourceFile, entry.declaration)
+            };
         }
     }
 
@@ -438,10 +440,8 @@ namespace ts.FindAllReferences {
             textSpan: documentSpan.textSpan,
             kind: writeAccess ? HighlightSpanKind.writtenReference : HighlightSpanKind.reference,
             isInString: entry.kind === EntryKind.StringLiteral ? true : undefined,
+            ...documentSpan.declarationSpan && { declarationSpan: documentSpan.declarationSpan }
         };
-        if (documentSpan.declarationSpan) {
-            span.declarationSpan = documentSpan.declarationSpan;
-        }
         return { fileName: documentSpan.fileName, span };
     }
 

src/services/goToDefinition.ts

@@ -273,20 +273,20 @@ namespace ts.GoToDefinition {
     function createDefinitionInfoFromName(declaration: Declaration, symbolKind: ScriptElementKind, symbolName: string, containerName: string): DefinitionInfo {
         const name = getNameOfDeclaration(declaration) || declaration;
         const sourceFile = name.getSourceFile();
-        const result: DefinitionInfo = {
+        const textSpan = createTextSpanFromNode(name, sourceFile);
+        return {
             fileName: sourceFile.fileName,
-            textSpan: createTextSpanFromNode(name, sourceFile),
+            textSpan,
             kind: symbolKind,
             name: symbolName,
             containerKind: undefined!, // TODO: GH#18217
             containerName,
+            ...FindAllReferences.toDeclarationSpan(
+                textSpan,
+                sourceFile,
+                FindAllReferences.getDeclarationForDeclarationSpan(declaration)
+            )
         };
-        FindAllReferences.setDeclarationSpan(
-            result,
-            sourceFile,
-            FindAllReferences.getDeclarationForDeclarationSpan(declaration)
-        );
-        return result;
     }
 
     function createDefinitionFromSignatureDeclaration(typeChecker: TypeChecker, decl: SignatureDeclaration): DefinitionInfo {

src/services/services.ts

@@ -1546,19 +1546,14 @@ namespace ts {
         function getOccurrencesAtPosition(fileName: string, position: number): ReadonlyArray<ReferenceEntry> | undefined {
             return flatMap(
                 getDocumentHighlights(fileName, position, [fileName]),
-                entry => entry.highlightSpans.map(highlightSpan => {
-                    const result: ReferenceEntry = {
-                        fileName: entry.fileName,
-                        textSpan: highlightSpan.textSpan,
-                        isWriteAccess: highlightSpan.kind === HighlightSpanKind.writtenReference,
-                        isDefinition: false,
-                        isInString: highlightSpan.isInString,
-                    };
-                    if (highlightSpan.declarationSpan) {
-                        result.declarationSpan = highlightSpan.declarationSpan;
-                    }
-                    return result;
-                })
+                entry => entry.highlightSpans.map<ReferenceEntry>(highlightSpan => ({
+                    fileName: entry.fileName,
+                    textSpan: highlightSpan.textSpan,
+                    isWriteAccess: highlightSpan.kind === HighlightSpanKind.writtenReference,
+                    isDefinition: false,
+                    ...highlightSpan.isInString && { isInString: true },
+                    ...highlightSpan.declarationSpan && { declarationSpan: highlightSpan.declarationSpan }
+                }))
             );
         }
 
@@ -1577,13 +1572,13 @@ namespace ts {
             const node = getTouchingPropertyName(sourceFile, position);
             if (isIdentifier(node) && (isJsxOpeningElement(node.parent) || isJsxClosingElement(node.parent)) && isIntrinsicJsxName(node.escapedText)) {
                 const { openingElement, closingElement } = node.parent.parent;
-                return [openingElement, closingElement].map(node => {
-                    const result: RenameLocation = {
+                return [openingElement, closingElement].map((node): RenameLocation => {
+                    const textSpan = createTextSpanFromNode(node.tagName, sourceFile);
+                    return {
                         fileName: sourceFile.fileName,
-                        textSpan: createTextSpanFromNode(node.tagName, sourceFile)
+                        textSpan,
+                        ...FindAllReferences.toDeclarationSpan(textSpan, sourceFile, node.parent)
                     };
-                    FindAllReferences.setDeclarationSpan(result, sourceFile, node.parent);
-                    return result;
                 });
             }
             else {

src/testRunner/unittests/tsserver/declarationFileMaps.ts

@@ -7,12 +7,12 @@ namespace ts.projectSystem {
         declarationOptions?: SpanFromSubstringOptions;
     }
     function documentSpanFromSubstring({ file, text, declarationText, options, declarationOptions }: DocumentSpanFromSubstring): DocumentSpan {
-        const result: DocumentSpan = { fileName: file.path, textSpan: textSpanFromSubstring(file.content, text, options) };
-        if (declarationText) {
-            const declarationSpan = documentSpanFromSubstring({ file, text: declarationText, options: declarationOptions });
-            result.declarationSpan = declarationSpan.textSpan;
-        }
-        return result;
+        const declarationSpan = declarationText !== undefined ? documentSpanFromSubstring({ file, text: declarationText, options: declarationOptions }) : undefined;
+        return {
+            fileName: file.path,
+            textSpan: textSpanFromSubstring(file.content, text, options),
+            ...declarationSpan && { declarationSpan: declarationSpan.textSpan }
+        };
     }
 
     function renameLocation(input: DocumentSpanFromSubstring): RenameLocation {

src/testRunner/unittests/tsserver/helpers.ts

@@ -523,13 +523,16 @@ namespace ts.projectSystem {
     }
     export function protocolDeclarationFileSpanFromSubstring({ declarationText, declarationOptions, ...rest }: DeclarationFileSpanFromSubString): protocol.DeclarationFileSpan {
         const result = protocolFileSpanFromSubstring(rest);
-        if (!declarationText) return result;
-        const declarationSpan = protocolFileSpanFromSubstring({ file: rest.file, text: declarationText, options: declarationOptions });
-        return {
-            ...result,
-            declarationStart: declarationSpan.start,
-            declarationEnd: declarationSpan.end
-        };
+        const declarationSpan = declarationText !== undefined ?
+            protocolFileSpanFromSubstring({ file: rest.file, text: declarationText, options: declarationOptions }) :
+            undefined;
+        return declarationSpan ?
+            {
+                ...result,
+                declarationStart: declarationSpan.start,
+                declarationEnd: declarationSpan.end
+            } :
+            result;
     }
 
     export interface ProtocolDeclarationTextSpanFromString {
@@ -542,16 +545,15 @@ namespace ts.projectSystem {
     export function protocolDeclarationTextSpanFromSubstring({ fileText, text, options, declarationText, declarationOptions }: ProtocolDeclarationTextSpanFromString): protocol.DeclarationTextSpan {
         const span = textSpanFromSubstring(fileText, text, options);
         const toLocation = protocolToLocation(fileText);
-        const result: protocol.DeclarationTextSpan = {
+        const declarationSpan = declarationText !== undefined ? textSpanFromSubstring(fileText, declarationText, declarationOptions) : undefined;
+        return {
             start: toLocation(span.start),
-            end: toLocation(textSpanEnd(span))
+            end: toLocation(textSpanEnd(span)),
+            ...declarationSpan && {
+                declarationStart: toLocation(declarationSpan.start),
+                declarationEnd: toLocation(textSpanEnd(declarationSpan))
+            }
         };
-        if (declarationText) {
-            const span = textSpanFromSubstring(fileText, declarationText, declarationOptions);
-            result.declarationStart = toLocation(span.start);
-            result.declarationEnd = toLocation(textSpanEnd(span));
-        }
-        return result;
     }
 
     export interface ProtocolRenameSpanFromSubstring extends ProtocolDeclarationTextSpanFromString {