diff --git a/src/testRunner/unittests/config/commandLineParsing.ts b/src/testRunner/unittests/config/commandLineParsing.ts
index 26a49df3dbb..c5a6c9a4869 100644
--- a/src/testRunner/unittests/config/commandLineParsing.ts
+++ b/src/testRunner/unittests/config/commandLineParsing.ts
@@ -365,6 +365,23 @@ namespace ts {
                     }
                 });
         });
+
+        it("parse --incremental", () => {
+            // --lib es6 0.ts
+            assertParseResult(["--incremental", "0.ts"],
+                {
+                    errors: [{
+                        messageText: "Option 'incremental' can only be specified in 'tsconfig.json' file.",
+                        category: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file.category,
+                        code: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file.code,
+                        file: undefined,
+                        start: undefined,
+                        length: undefined,
+                    }],
+                    fileNames: ["0.ts"],
+                    options: {}
+                });
+        });
     });
 
     describe("unittests:: config:: commandLineParsing:: parseBuildOptions", () => {
@@ -456,6 +473,23 @@ namespace ts {
                 });
         });
 
+        it("parse build with --incremental ", () => {
+            // --lib es6 0.ts
+            assertParseResult(["--incremental", "tests"],
+                {
+                    errors: [{
+                        messageText: "Unknown build option '--incremental'.",
+                        category: Diagnostics.Unknown_build_option_0.category,
+                        code: Diagnostics.Unknown_build_option_0.code,
+                        file: undefined,
+                        start: undefined,
+                        length: undefined,
+                    }],
+                    projects: ["tests"],
+                    buildOptions: { }
+                });
+        });
+
         describe("Combining options that make no sense together", () => {
             function verifyInvalidCombination(flag1: keyof BuildOptions, flag2: keyof BuildOptions) {
                 it(`--${flag1} and --${flag2} together is invalid`, () => {