diff --git a/src/harness/unittests/extractTestHelpers.ts b/src/harness/unittests/extractTestHelpers.ts
index 49c2c1d327704..fb2a94c361a0b 100644
--- a/src/harness/unittests/extractTestHelpers.ts
+++ b/src/harness/unittests/extractTestHelpers.ts
@@ -103,6 +103,7 @@ namespace ts {
         getScriptVersion: notImplemented,
         getScriptSnapshot: notImplemented,
         getDefaultLibFileName: notImplemented,
+        getCurrentDirectory: notImplemented,
     };
 
     export function testExtractSymbol(caption: string, text: string, baselineFolder: string, description: DiagnosticMessage) {
diff --git a/src/services/types.ts b/src/services/types.ts
index 7ec559be92283..31c05a45dc0d8 100644
--- a/src/services/types.ts
+++ b/src/services/types.ts
@@ -163,6 +163,7 @@ namespace ts {
         getScriptSnapshot(fileName: string): IScriptSnapshot | undefined;
         getLocalizedDiagnosticMessages?(): any;
         getCancellationToken?(): HostCancellationToken;
+        getCurrentDirectory(): string;
         getDefaultLibFileName(options: CompilerOptions): string;
         log?(s: string): void;
         trace?(s: string): void;
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index ab39d0a6d6ccc..72c3b665617ff 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -3884,6 +3884,7 @@ declare namespace ts {
         getScriptSnapshot(fileName: string): IScriptSnapshot | undefined;
         getLocalizedDiagnosticMessages?(): any;
         getCancellationToken?(): HostCancellationToken;
+        getCurrentDirectory(): string;
         getDefaultLibFileName(options: CompilerOptions): string;
         log?(s: string): void;
         trace?(s: string): void;
diff --git a/tests/baselines/reference/api/typescript.d.ts b/tests/baselines/reference/api/typescript.d.ts
index 976d50942ae1b..374a9f4120289 100644
--- a/tests/baselines/reference/api/typescript.d.ts
+++ b/tests/baselines/reference/api/typescript.d.ts
@@ -3884,6 +3884,7 @@ declare namespace ts {
         getScriptSnapshot(fileName: string): IScriptSnapshot | undefined;
         getLocalizedDiagnosticMessages?(): any;
         getCancellationToken?(): HostCancellationToken;
+        getCurrentDirectory(): string;
         getDefaultLibFileName(options: CompilerOptions): string;
         log?(s: string): void;
         trace?(s: string): void;