diff --git a/src/compiler/tsc.ts b/src/compiler/tsc.ts
index fc6d65b45e9..232360116f3 100644
--- a/src/compiler/tsc.ts
+++ b/src/compiler/tsc.ts
@@ -87,7 +87,7 @@ namespace ts {
         if (diagnostic.file) {
             let loc = getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start);
             const relativeFileName = host
-                ? toRelativePath(diagnostic.file.fileName, host.getCurrentDirectory(), fileName => host.getCanonicalFileName(fileName))
+                ? convertToRelativePath(diagnostic.file.fileName, host.getCurrentDirectory(), fileName => host.getCanonicalFileName(fileName))
                 : diagnostic.file.fileName;
 
             output += `${ relativeFileName }(${ loc.line + 1 },${ loc.character + 1 }): `;
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index fb6d2686b15..fd991039d3e 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -2182,7 +2182,7 @@ namespace ts {
         return result;
     }
 
-    export function toRelativePath(absoluteOrRelativePath: string, basePath: string, getCanonicalFileName: (path: string) => string): string {
+    export function convertToRelativePath(absoluteOrRelativePath: string, basePath: string, getCanonicalFileName: (path: string) => string): string {
         return !isRootedDiskPath(absoluteOrRelativePath)
             ? absoluteOrRelativePath
             : getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /* isAbsolutePathAnUrl */ false);
diff --git a/src/harness/projectsRunner.ts b/src/harness/projectsRunner.ts
index 52d4b85f6b8..e587aad3ddb 100644
--- a/src/harness/projectsRunner.ts
+++ b/src/harness/projectsRunner.ts
@@ -377,10 +377,10 @@ class ProjectRunner extends RunnerBase {
                             bug: testCase.bug,
                             rootDir: testCase.rootDir,
                             resolvedInputFiles: ts.map(compilerResult.program.getSourceFiles(), inputFile => {
-                                return ts.toRelativePath(inputFile.fileName, getCurrentDirectory(), path => Harness.Compiler.getCanonicalFileName(path));
+                                return ts.convertToRelativePath(inputFile.fileName, getCurrentDirectory(), path => Harness.Compiler.getCanonicalFileName(path));
                             }),
                             emittedFiles: ts.map(compilerResult.outputFiles, outputFile => {
-                                return ts.toRelativePath(outputFile.emittedFileName, getCurrentDirectory(), path => Harness.Compiler.getCanonicalFileName(path));
+                                return ts.convertToRelativePath(outputFile.emittedFileName, getCurrentDirectory(), path => Harness.Compiler.getCanonicalFileName(path));
                             })
                         };