Remove secondary reference lookup implementation

src/compiler/emitter.ts

@@ -725,7 +725,8 @@ namespace ts {
             fileExists: f => host.fileExists(f),
             directoryExists: host.directoryExists && (f => host.directoryExists!(f)),
             useCaseSensitiveFileNames: () => host.useCaseSensitiveFileNames(),
-            getProgramBuildInfo: returnUndefined
+            getProgramBuildInfo: returnUndefined,
+            getSourceFileFromReference: returnUndefined,
         };
         emitFiles(
             notImplementedResolver,

src/compiler/program.ts

@@ -1442,7 +1442,8 @@ namespace ts {
                 },
                 ...(host.directoryExists ? { directoryExists: f => host.directoryExists!(f) } : {}),
                 useCaseSensitiveFileNames: () => host.useCaseSensitiveFileNames(),
-                getProgramBuildInfo: () => program.getProgramBuildInfo && program.getProgramBuildInfo()
+                getProgramBuildInfo: () => program.getProgramBuildInfo && program.getProgramBuildInfo(),
+                getSourceFileFromReference: (file, ref) => program.getSourceFileFromReference(file, ref),
             };
         }
 
@@ -2127,7 +2128,7 @@ namespace ts {
         }
 
         /** This should have similar behavior to 'processSourceFile' without diagnostics or mutation. */
-        function getSourceFileFromReference(referencingFile: SourceFile, ref: FileReference): SourceFile | undefined {
+        function getSourceFileFromReference(referencingFile: SourceFile | UnparsedSource, ref: FileReference): SourceFile | undefined {
             return getSourceFileFromReferenceWorker(resolveTripleslashReference(ref.fileName, referencingFile.fileName), fileName => filesByName.get(toPath(fileName)) || undefined);
         }
 

src/compiler/transformers/declarations.ts

@@ -348,7 +348,7 @@ namespace ts {
         function collectReferences(sourceFile: SourceFile | UnparsedSource, ret: Map<SourceFile>) {
             if (noResolve || (!isUnparsedSource(sourceFile) && isSourceFileJS(sourceFile))) return ret;
             forEach(sourceFile.referencedFiles, f => {
-                const elem = tryResolveScriptReference(host, sourceFile, f);
+                const elem = host.getSourceFileFromReference(sourceFile, f);
                 if (elem) {
                     ret.set("" + getOriginalNodeId(elem), elem);
                 }

src/compiler/types.ts

@@ -2975,7 +2975,7 @@ namespace ts {
         // For testing purposes only.
         /* @internal */ structureIsReused?: StructureIsReused;
 
-        /* @internal */ getSourceFileFromReference(referencingFile: SourceFile, ref: FileReference): SourceFile | undefined;
+        /* @internal */ getSourceFileFromReference(referencingFile: SourceFile | UnparsedSource, ref: FileReference): SourceFile | undefined;
         /* @internal */ getLibFileFromReference(ref: FileReference): SourceFile | undefined;
 
         /** Given a source file, get the name of the package it was imported from. */
@@ -5399,6 +5399,7 @@ namespace ts {
 
         writeFile: WriteFileCallback;
         getProgramBuildInfo(): ProgramBuildInfo | undefined;
+        getSourceFileFromReference: Program["getSourceFileFromReference"];
     }
 
     export interface TransformationContext {

src/compiler/utilities.ts

@@ -2611,13 +2611,6 @@ namespace ts {
         return undefined;
     }
 
-    export function tryResolveScriptReference(host: ScriptReferenceHost, sourceFile: SourceFile | UnparsedSource, reference: FileReference) {
-        if (!host.getCompilerOptions().noResolve) {
-            const referenceFileName = isRootedDiskPath(reference.fileName) ? reference.fileName : combinePaths(getDirectoryPath(sourceFile.fileName), reference.fileName);
-            return host.getSourceFile(referenceFileName);
-        }
-    }
-
     export function getAncestor(node: Node | undefined, kind: SyntaxKind): Node | undefined {
         while (node) {
             if (node.kind === kind) {

src/services/goToDefinition.ts

@@ -108,7 +108,7 @@ namespace ts.GoToDefinition {
     export function getReferenceAtPosition(sourceFile: SourceFile, position: number, program: Program): { fileName: string, file: SourceFile } | undefined {
         const referencePath = findReferenceInPosition(sourceFile.referencedFiles, position);
         if (referencePath) {
-            const file = tryResolveScriptReference(program, sourceFile, referencePath);
+            const file = program.getSourceFileFromReference(sourceFile, referencePath);
             return file && { fileName: referencePath.fileName, file };
         }