Improvements to find-all-references for import types

Author: Andy Hanson

src/compiler/types.ts

@@ -3252,12 +3252,17 @@ namespace ts {
     /* @internal */
     export type AnyImportOrReExport = AnyImportSyntax | ExportDeclaration;
 
+    /* @internal */
+    export interface ValidImportTypeNode extends ImportTypeNode {
+        argument: LiteralTypeNode & { literal: StringLiteral };
+    }
+
     /* @internal */
     export type AnyValidImportOrReExport =
         | (ImportDeclaration | ExportDeclaration) & { moduleSpecifier: StringLiteral }
         | ImportEqualsDeclaration & { moduleReference: ExternalModuleReference & { expression: StringLiteral } }
         | RequireOrImportCall
-        | ImportTypeNode & { argument: LiteralType };
+        | ValidImportTypeNode;
 
     /* @internal */
     export type RequireOrImportCall = CallExpression & { arguments: [StringLiteralLike] };

src/compiler/utilities.ts

@@ -1722,6 +1722,10 @@ namespace ts {
     }
 
     export function importFromModuleSpecifier(node: StringLiteralLike): AnyValidImportOrReExport {
+        return tryGetImportFromModuleSpecifier(node) || Debug.fail(Debug.showSyntaxKind(node.parent));
+    }
+
+    export function tryGetImportFromModuleSpecifier(node: StringLiteralLike): AnyValidImportOrReExport | undefined {
         switch (node.parent.kind) {
             case SyntaxKind.ImportDeclaration:
             case SyntaxKind.ExportDeclaration:
@@ -1731,9 +1735,10 @@ namespace ts {
             case SyntaxKind.CallExpression:
                 return node.parent as AnyValidImportOrReExport;
             case SyntaxKind.LiteralType:
-                return cast(node.parent.parent, isImportTypeNode) as ImportTypeNode & { argument: LiteralType };
+                Debug.assert(isStringLiteral(node));
+                return tryCast(node.parent.parent, isImportTypeNode) as ValidImportTypeNode | undefined;
             default:
-                return Debug.fail(Debug.showSyntaxKind(node.parent));
+                return undefined;
         }
     }
 

src/services/findAllReferences.ts

@@ -236,7 +236,7 @@ namespace ts.FindAllReferences.Core {
     export function getReferencedSymbolsForNode(position: number, node: Node, program: Program, sourceFiles: ReadonlyArray<SourceFile>, cancellationToken: CancellationToken, options: Options = {}, sourceFilesSet: ReadonlyMap<true> = arrayToSet(sourceFiles, f => f.fileName)): SymbolAndEntries[] | undefined {
         if (isSourceFile(node)) {
             const reference = GoToDefinition.getReferenceAtPosition(node, position, program);
-            return reference && getReferencedSymbolsForModule(program, program.getTypeChecker().getMergedSymbol(reference.file.symbol), sourceFiles, sourceFilesSet);
+            return reference && getReferencedSymbolsForModule(program, program.getTypeChecker().getMergedSymbol(reference.file.symbol), /*excludeImportTypeOfExportEquals*/ false, sourceFiles, sourceFilesSet);
         }
 
         if (!options.implementations) {
@@ -247,45 +247,44 @@ namespace ts.FindAllReferences.Core {
         }
 
         const checker = program.getTypeChecker();
-        const symbol = checker.getSymbolAtLocation(node);
+        let symbol = checker.getSymbolAtLocation(node);
 
         // Could not find a symbol e.g. unknown identifier
         if (!symbol) {
             // String literal might be a property (and thus have a symbol), so do this here rather than in getReferencedSymbolsSpecial.
             return !options.implementations && isStringLiteral(node) ? getReferencesForStringLiteral(node, sourceFiles, cancellationToken) : undefined;
         }
 
-        if (symbol.flags & SymbolFlags.Module && isModuleReferenceLocation(node)) {
-            return getReferencedSymbolsForModule(program, symbol, sourceFiles, sourceFilesSet);
+        let moduleReferences: SymbolAndEntries[] = emptyArray;
+        if (isModuleSymbol(symbol)) {
+            const exportEquals = symbol.exports.get(InternalSymbolName.ExportEquals);
+            // If !!exportEquals, we're about to add references to `import("mod")` anyway, so don't double-count them.
+            moduleReferences = getReferencedSymbolsForModule(program, symbol, !!exportEquals, sourceFiles, sourceFilesSet);
+            if (!exportEquals) return moduleReferences;
+            // Continue to get references to 'export ='.
+            symbol = skipAlias(exportEquals, checker);
+            node = undefined;
         }
-
-        return getReferencedSymbolsForSymbol(symbol, node, sourceFiles, sourceFilesSet, checker, cancellationToken, options);
+        return concatenate(moduleReferences, getReferencedSymbolsForSymbol(symbol, node, sourceFiles, sourceFilesSet, checker, cancellationToken, options));
     }
 
-    function isModuleReferenceLocation(node: Node): boolean {
-        if (!isStringLiteralLike(node)) {
-            return false;
-        }
-        switch (node.parent.kind) {
-            case SyntaxKind.ModuleDeclaration:
-            case SyntaxKind.ExternalModuleReference:
-            case SyntaxKind.ImportDeclaration:
-            case SyntaxKind.ExportDeclaration:
-                return true;
-            case SyntaxKind.LiteralType:
-                return isImportTypeNode(node.parent.parent);
-            case SyntaxKind.CallExpression:
-                return isRequireCall(node.parent as CallExpression, /*checkArgumentIsStringLiteralLike*/ false) || isImportCall(node.parent as CallExpression);
-            default:
-                return false;
-        }
+    function isModuleSymbol(symbol: Symbol): boolean {
+        return symbol.flags & SymbolFlags.Module && symbol.declarations.some(isSourceFile);
     }
 
-    function getReferencedSymbolsForModule(program: Program, symbol: Symbol, sourceFiles: ReadonlyArray<SourceFile>, sourceFilesSet: ReadonlyMap<true>): SymbolAndEntries[] {
+    function getReferencedSymbolsForModule(program: Program, symbol: Symbol, excludeImportTypeOfExportEquals: boolean, sourceFiles: ReadonlyArray<SourceFile>, sourceFilesSet: ReadonlyMap<true>): SymbolAndEntries[] {
         Debug.assert(!!symbol.valueDeclaration);
 
-        const references = findModuleReferences(program, sourceFiles, symbol).map<Entry>(reference => {
+        const references = mapDefined<ModuleReference, Entry>(findModuleReferences(program, sourceFiles, symbol), reference => {
             if (reference.kind === "import") {
+                const parent = reference.literal.parent;
+                if (isLiteralTypeNode(parent)) {
+                    const importType = cast(parent.parent, isImportTypeNode);
+                    if (excludeImportTypeOfExportEquals && !importType.qualifier) {
+                        return undefined;
+                    }
+                }
+                // import("foo") with no qualifier will reference the `export =` of the module, which may be referenced anyway.
                 return { type: "node", node: reference.literal };
             }
             else {
@@ -308,11 +307,12 @@ namespace ts.FindAllReferences.Core {
                     }
                     break;
                 default:
+                    // This may be merged with something.
                     Debug.fail("Expected a module symbol to be declared by a SourceFile or ModuleDeclaration.");
             }
         }
 
-        return [{ definition: { type: "symbol", symbol }, references }];
+        return references.length ? [{ definition: { type: "symbol", symbol }, references }] : emptyArray;
     }
 
     /** getReferencedSymbols for special node kinds. */
@@ -345,21 +345,21 @@ namespace ts.FindAllReferences.Core {
     }
 
     /** Core find-all-references algorithm for a normal symbol. */
-    function getReferencedSymbolsForSymbol(symbol: Symbol, node: Node, sourceFiles: ReadonlyArray<SourceFile>, sourceFilesSet: ReadonlyMap<true>, checker: TypeChecker, cancellationToken: CancellationToken, options: Options): SymbolAndEntries[] {
-        symbol = skipPastExportOrImportSpecifierOrUnion(symbol, node, checker) || symbol;
+    function getReferencedSymbolsForSymbol(symbol: Symbol, node: Node | undefined, sourceFiles: ReadonlyArray<SourceFile>, sourceFilesSet: ReadonlyMap<true>, checker: TypeChecker, cancellationToken: CancellationToken, options: Options): SymbolAndEntries[] {
+        symbol = node && skipPastExportOrImportSpecifierOrUnion(symbol, node, checker) || symbol;
 
         // Compute the meaning from the location and the symbol it references
-        const searchMeaning = getIntersectingMeaningFromDeclarations(node, symbol);
+        const searchMeaning = node ? getIntersectingMeaningFromDeclarations(node, symbol) : SemanticMeaning.All;
 
         const result: SymbolAndEntries[] = [];
-        const state = new State(sourceFiles, sourceFilesSet, getSpecialSearchKind(node), checker, cancellationToken, searchMeaning, options, result);
+        const state = new State(sourceFiles, sourceFilesSet, node ? getSpecialSearchKind(node) : SpecialSearchKind.None, checker, cancellationToken, searchMeaning, options, result);
 
-        if (node.kind === SyntaxKind.DefaultKeyword) {
+        if (node && node.kind === SyntaxKind.DefaultKeyword) {
             addReference(node, symbol, state);
             searchForImportsOfExport(node, symbol, { exportingModuleSymbol: Debug.assertDefined(symbol.parent, "Expected export symbol to have a parent"), exportKind: ExportKind.Default }, state);
         }
         else {
-            const search = state.createSearch(node, symbol, /*comingFrom*/ undefined, { allSearchSymbols: populateSearchSymbolSet(symbol, node, checker, options.implementations) });
+            const search = state.createSearch(node, symbol, /*comingFrom*/ undefined, { allSearchSymbols: node ? populateSearchSymbolSet(symbol, node, checker, options.implementations) : [symbol] });
 
             // Try to get the smallest valid scope that we can limit our search to;
             // otherwise we'll need to search globally (i.e. include each file).
@@ -499,7 +499,7 @@ namespace ts.FindAllReferences.Core {
         }
 
         /** @param allSearchSymbols set of additinal symbols for use by `includes`. */
-        createSearch(location: Node, symbol: Symbol, comingFrom: ImportExport | undefined, searchOptions: { text?: string, allSearchSymbols?: Symbol[] } = {}): Search {
+        createSearch(location: Node | undefined, symbol: Symbol, comingFrom: ImportExport | undefined, searchOptions: { text?: string, allSearchSymbols?: Symbol[] } = {}): Search {
             // Note: if this is an external module symbol, the name doesn't include quotes.
             // Note: getLocalSymbolForExportDefault handles `export default class C {}`, but not `export default C` or `export { C as default }`.
             // The other two forms seem to be handled downstream (e.g. in `skipPastExportOrImportSpecifier`), so special-casing the first form
@@ -509,7 +509,7 @@ namespace ts.FindAllReferences.Core {
                 allSearchSymbols = [symbol],
             } = searchOptions;
             const escapedText = escapeLeadingUnderscores(text);
-            const parents = this.options.implementations && getParentSymbolsOfPropertyAccess(location, symbol, this.checker);
+            const parents = this.options.implementations && location && getParentSymbolsOfPropertyAccess(location, symbol, this.checker);
             return { symbol, comingFrom, text, escapedText, parents, allSearchSymbols, includes: sym => contains(allSearchSymbols, sym) };
         }
 
@@ -559,11 +559,7 @@ namespace ts.FindAllReferences.Core {
         if (singleReferences.length) {
             const addRef = state.referenceAdder(exportSymbol);
             for (const singleRef of singleReferences) {
-                // At `default` in `import { default as x }` or `export { default as x }`, do add a reference, but do not rename.
-                if (hasMatchingMeaning(singleRef, state) &&
-                    !(state.options.isForRename && (isExportSpecifier(singleRef.parent) || isImportSpecifier(singleRef.parent)) && singleRef.escapedText === InternalSymbolName.Default)) {
-                    addRef(singleRef);
-                }
+                if (shouldAddSingleReference(singleRef, state)) addRef(singleRef);
             }
         }
 
@@ -593,6 +589,15 @@ namespace ts.FindAllReferences.Core {
         }
     }
 
+    function shouldAddSingleReference(singleRef: Identifier | StringLiteral, state: State): boolean {
+        if (!hasMatchingMeaning(singleRef, state)) return false;
+        if (!state.options.isForRename) return true;
+        // Don't rename an import type `import("./module-name")` when renaming `name` in export = name`
+        if (!isIdentifier(singleRef)) return false;
+        // At `default` in `import { default as x }` or `export { default as x }`, do add a reference, but do not rename.
+        return !((isExportSpecifier(singleRef.parent) || isImportSpecifier(singleRef.parent)) && singleRef.escapedText === InternalSymbolName.Default);
+    }
+
     // Go to the symbol we imported from and find references for it.
     function searchForImportedSymbol(symbol: Symbol, state: State): void {
         for (const declaration of symbol.declarations) {

src/services/importTracker.ts

@@ -3,9 +3,9 @@
 namespace ts.FindAllReferences {
     export interface ImportsResult {
         /** For every import of the symbol, the location and local symbol for the import. */
-        importSearches: [Identifier, Symbol][];
+        importSearches: ReadonlyArray<[Identifier, Symbol]>;
         /** For rename imports/exports `{ foo as bar }`, `foo` is not a local, so it may be added as a reference immediately without further searching. */
-        singleReferences: Identifier[];
+        singleReferences: ReadonlyArray<Identifier | StringLiteral>;
         /** List of source files that may (or may not) use the symbol via a namespace. (For UMD modules this is every file.) */
         indirectUsers: ReadonlyArray<SourceFile>;
     }
@@ -33,7 +33,7 @@ namespace ts.FindAllReferences {
     interface AmbientModuleDeclaration extends ModuleDeclaration { body?: ModuleBlock; }
     type SourceFileLike = SourceFile | AmbientModuleDeclaration;
     // Identifier for the case of `const x = require("y")`.
-    type Importer = AnyImportOrReExport | ImportTypeNode | Identifier;
+    type Importer = AnyImportOrReExport | ValidImportTypeNode | Identifier;
     type ImporterOrCallExpression = Importer | CallExpression;
 
     /** Returns import statements that directly reference the exporting module, and a list of files that may access the module through a namespace. */
@@ -135,13 +135,7 @@ namespace ts.FindAllReferences {
                             break;
 
                         case SyntaxKind.ImportType:
-                            if (direct.qualifier) {
-                                // `import("foo").x` named import
-                                directImports.push(direct);
-                            }
-                            else {
-                                // TODO: GH#23879
-                            }
+                            directImports.push(direct);
                             break;
 
                         default:
@@ -205,7 +199,7 @@ namespace ts.FindAllReferences {
      */
     function getSearchesFromDirectImports(directImports: Importer[], exportSymbol: Symbol, exportKind: ExportKind, checker: TypeChecker, isForRename: boolean): Pick<ImportsResult, "importSearches" | "singleReferences"> {
         const importSearches: [Identifier, Symbol][] = [];
-        const singleReferences: Identifier[] = [];
+        const singleReferences: (Identifier | StringLiteral)[] = [];
         function addSearch(location: Identifier, symbol: Symbol): void {
             importSearches.push([location, symbol]);
         }
@@ -232,8 +226,13 @@ namespace ts.FindAllReferences {
             }
 
             if (decl.kind === SyntaxKind.ImportType) {
-                if (decl.qualifier) { // TODO: GH#23879
-                    singleReferences.push(decl.qualifier.kind === SyntaxKind.Identifier ? decl.qualifier : decl.qualifier.right);
+                if (decl.qualifier) {
+                    if (isIdentifier(decl.qualifier) && decl.qualifier.escapedText === symbolName(exportSymbol)) {
+                        singleReferences.push(decl.qualifier);
+                    }
+                }
+                else if (exportKind === ExportKind.ExportEquals) {
+                    singleReferences.push(decl.argument.literal);
                 }
                 return;
             }

src/services/rename.ts

@@ -36,6 +36,9 @@ namespace ts.Rename {
                     return undefined;
                 }
 
+                // Can't rename a module name.
+                if (isStringLiteralLike(node) && tryGetImportFromModuleSpecifier(node)) return undefined;
+
                 const kind = SymbolDisplay.getSymbolKind(typeChecker, symbol, node);
                 const specifierName = (isImportOrExportSpecifierName(node) || isStringOrNumericLiteral(node) && node.parent.kind === SyntaxKind.ComputedPropertyName)
                     ? stripQuotes(getTextOfIdentifierOrLiteral(node))

src/services/utilities.ts

@@ -107,6 +107,10 @@ namespace ts {
             Debug.assert(isJSDocTemplateTag(node.parent.parent)); // Else would be handled by isDeclarationName
             return SemanticMeaning.Type;
         }
+        else if (isLiteralTypeNode(node.parent)) {
+            // This might be T["name"], which is actually referencing a property and not a type. So allow both meanings.
+            return SemanticMeaning.Type | SemanticMeaning.Value;
+        }
         else {
             return SemanticMeaning.Value;
         }

tests/cases/fourslash/findAllRefsExportEquals.ts

@@ -0,0 +1,17 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /a.ts
+////type [|{| "isWriteAccess": true, "isDefinition": true |}T|] = number;
+////export = [|T|];
+
+// @Filename: /b.ts
+////import [|{| "isWriteAccess": true, "isDefinition": true |}T|] = require("[|./a|]");
+
+// TODO: GH#23879 Should be `verify.singleReferenceGroup("type T = number")
+const [r0, r1, r2, r3] = test.ranges();
+const mod = { definition: 'module "/a"', ranges: [r3] };
+const a = { definition: "type T = number", ranges: [r0, r1] };
+const b = { definition: '(alias) type T = number\nimport T = require("./a")', ranges: [r2] };
+verify.referenceGroups([r0, r1], [a, b]);
+verify.referenceGroups(r2, [b, a]);
+verify.referenceGroups(r3, [mod, a, b]);

tests/cases/fourslash/findAllRefsForModuleGlobal.ts

@@ -9,7 +9,4 @@
 ////declare module "[|{| "isWriteAccess": true, "isDefinition": true |}foo|]" {}
 
 verify.noErrors();
-
-const ranges = test.ranges();
-const [r0, r1, r2] = ranges;
 verify.singleReferenceGroup('module "/node_modules/foo/index"');