diff --git a/packages/jest-editor-support/src/__tests__/process.test.js b/packages/jest-editor-support/src/__tests__/process.test.js
index 117cbf2d0b0e..7b4bc0e844b5 100644
--- a/packages/jest-editor-support/src/__tests__/process.test.js
+++ b/packages/jest-editor-support/src/__tests__/process.test.js
@@ -86,10 +86,7 @@ describe('createProcess', () => {
   });
 
   it('defines the "CI" environment variable', () => {
-    const expected = {
-      ...process.env,
-      CI: 'true',
-    };
+    const expected = Object.assign({}, process.env, {CI: 'true'});
 
     const workspace: any = {pathToJest: ''};
     const args = [];
diff --git a/packages/jest-editor-support/src/__tests__/runner.test.js b/packages/jest-editor-support/src/__tests__/runner.test.js
index 8fd651296338..4b8257a25424 100644
--- a/packages/jest-editor-support/src/__tests__/runner.test.js
+++ b/packages/jest-editor-support/src/__tests__/runner.test.js
@@ -260,6 +260,7 @@ describe('events', () => {
     fakeProcess = (new EventEmitter(): any);
     fakeProcess.stdout = new EventEmitter();
     fakeProcess.stderr = new EventEmitter();
+    fakeProcess.kill = () => {};
 
     (createProcess: any).mockImplementation(() => fakeProcess);