Fix tests on windows (#3785)

tests_integration/__tests__/plugin-extensions.js

@@ -1,10 +1,11 @@
 "use strict";
 
 const runPrettier = require("../runPrettier");
+const EOL = require("os").EOL;
 
 describe("uses 'extensions' from languages to determine parser", () => {
   runPrettier("plugins/extensions", ["*.foo", "--plugin=./plugin"]).test({
-    stdout: "!contents\n",
+    stdout: "!contents" + EOL,
     stderr: "",
     status: 0,
     write: []

tests_integration/__tests__/plugin-preprocess.js

@@ -1,10 +1,11 @@
 "use strict";
 
 const runPrettier = require("../runPrettier");
+const EOL = require("os").EOL;
 
 describe("parser preprocess function is used to reshape input text", () => {
   runPrettier("plugins/preprocess", ["*.foo", "--plugin=./plugin"]).test({
-    stdout: "preprocessed:contents\n",
+    stdout: "preprocessed:contents" + EOL,
     stderr: "",
     status: 0,
     write: []

tests_integration/__tests__/plugin-resolution.js

@@ -1,10 +1,11 @@
 "use strict";
 
 const runPrettier = require("../runPrettier");
+const EOL = require("os").EOL;
 
 describe("automatically loads 'prettier-plugin-*' from package.json devDependencies", () => {
   runPrettier("plugins/automatic", ["file.txt", "--parser=foo"]).test({
-    stdout: "foo+contents\n",
+    stdout: "foo+contents" + EOL,
     stderr: "",
     status: 0,
     write: []
@@ -13,7 +14,7 @@ describe("automatically loads 'prettier-plugin-*' from package.json devDependenc
 
 describe("automatically loads '@prettier/plugin-*' from package.json dependencies", () => {
   runPrettier("plugins/automatic", ["file.txt", "--parser=bar"]).test({
-    stdout: "bar+contents\n",
+    stdout: "bar+contents" + EOL,
     stderr: "",
     status: 0,
     write: []