From ce8f0ee84f01c2f50fe166f642d5e7720b49d864 Mon Sep 17 00:00:00 2001
From: Lila Conlee <lila.conlee@gmail.com>
Date: Mon, 3 Dec 2018 14:33:36 -0500
Subject: [PATCH] Yield null from cy.writeFile (#2731)

- Fixes #2466
- [Docs PR](https://github.com/cypress-io/cypress-documentation/pull/1117)

Should be part of 4.0.0
---
 packages/driver/src/cy/commands/files.coffee           |  5 +----
 .../cypress/integration/commands/files_spec.coffee     | 10 ++--------
 2 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/packages/driver/src/cy/commands/files.coffee b/packages/driver/src/cy/commands/files.coffee
index 6578adbc4d88..40f7a3009f07 100644
--- a/packages/driver/src/cy/commands/files.coffee
+++ b/packages/driver/src/cy/commands/files.coffee
@@ -94,16 +94,13 @@ module.exports = (Commands, Cypress, cy, state, config) ->
         })
 
       if _.isObject(contents)
-        objContents = contents
         contents = JSON.stringify(contents, null, 2)
 
       Cypress.backend("write:file", fileName, contents, _.pick(options, ["encoding", "flag"]))
       .then ({ contents, filePath }) ->
         consoleProps["File Path"] = filePath
         consoleProps["Contents"] = contents
-        if objContents?
-          return objContents
-        return contents
+        return null
       .catch Promise.TimeoutError, (err) ->
         $utils.throwErrByPath "files.timed_out", {
           onFail: options._log
diff --git a/packages/driver/test/cypress/integration/commands/files_spec.coffee b/packages/driver/test/cypress/integration/commands/files_spec.coffee
index b767fbcb5369..b23d0bf22d54 100644
--- a/packages/driver/test/cypress/integration/commands/files_spec.coffee
+++ b/packages/driver/test/cypress/integration/commands/files_spec.coffee
@@ -286,17 +286,11 @@ describe "src/cy/commands/files", ->
           }
         )
 
-    it "sets the contents as the subject", ->
+    it "yields null", ->
       Cypress.backend.resolves(okResponse)
 
       cy.writeFile("foo.txt", "contents").then (subject) ->
-        expect(subject).to.equal("contents")
-       
-    it "sets a JSON as the subject", ->
-      Cypress.backend.resolves(okResponse)
-
-      cy.writeFile("foo.json", { name: "Test" }).then (subject) ->
-        expect(subject.name).to.equal("Test")
+        expect(subject).to.not.exist
 
     it "can write a string", ->
       Cypress.backend.resolves(okResponse)