Chore: add integration tests for autofixing (fixes #5909) (#7349)

tests/bin/eslint.js

@@ -1,29 +1,33 @@
 /**
- * @fileoverview Tests for the eslint.js executable.
+ * @fileoverview Integration tests for the eslint.js executable.
  * @author Teddy Katz
  */
 
 "use strict";
 
 const childProcess = require("child_process");
+const fs = require("fs");
 const assert = require("chai").assert;
 const EXECUTABLE_PATH = require("path").resolve(`${__dirname}/../../bin/eslint.js`);
 
+/**
+* Returns a Promise for when a child process exits
+* @param {ChildProcess} exitingProcess The child process
+* @returns {Promise<number>} A Promise that fulfills with the exit code when the child process exits
+*/
+function awaitExit(exitingProcess) {
+    return new Promise(resolve => exitingProcess.once("exit", resolve));
+}
+
 /**
 * Asserts that the exit code of a given child process will equal the given value.
 * @param {ChildProcess} exitingProcess The child process
 * @param {number} expectedExitCode The expected exit code of the child process
 * @returns {Promise} A Promise that fufills if the exit code ends up matching, and rejects otherwise.
 */
 function assertExitCode(exitingProcess, expectedExitCode) {
-    return new Promise((resolve, reject) => {
-        exitingProcess.once("exit", exitCode => {
-            if (exitCode === expectedExitCode) {
-                resolve();
-            } else {
-                reject(new Error(`Expected an exit code of ${expectedExitCode} but got ${exitCode}.`));
-            }
-        });
+    return awaitExit(exitingProcess).then(exitCode => {
+        assert.strictEqual(exitCode, expectedExitCode, `Expected an exit code of ${expectedExitCode} but got ${exitCode}.`);
     });
 }
 
@@ -35,13 +39,8 @@ function assertExitCode(exitingProcess, expectedExitCode) {
 function getStdout(runningProcess) {
     let stdout = "";
 
-    runningProcess.stdout.on("data", data => {
-        stdout += data;
-    });
-
-    return new Promise(resolve => {
-        runningProcess.once("exit", () => resolve(stdout));
-    });
+    runningProcess.stdout.on("data", data => (stdout += data));
+    return awaitExit(runningProcess).then(() => stdout);
 }
 
 describe("bin/eslint.js", () => {
@@ -108,6 +107,41 @@ describe("bin/eslint.js", () => {
         it("has exit code 1 if a syntax error is thrown", () => assertExitCode(runESLint(["README.md"]), 1));
     });
 
+    describe("automatically fixing files", () => {
+        const fixturesPath = `${__dirname}/../fixtures/autofix-integration`;
+        const tempFilePath = `${fixturesPath}/temp.js`;
+        const startingText = fs.readFileSync(`${fixturesPath}/left-pad.js`).toString();
+        const expectedFixedText = fs.readFileSync(`${fixturesPath}/left-pad-expected.js`).toString();
+
+        beforeEach(() => {
+            fs.writeFileSync(tempFilePath, startingText);
+        });
+
+        it("has exit code 0 and fixes a file if all rules can be fixed", () => {
+            const child = runESLint(["--fix", "--no-eslintrc", "--no-ignore", tempFilePath]);
+            const exitCodeAssertion = assertExitCode(child, 0);
+            const outputFileAssertion = awaitExit(child).then(() => {
+                assert.strictEqual(fs.readFileSync(tempFilePath).toString(), expectedFixedText);
+            });
+
+            return Promise.all([exitCodeAssertion, outputFileAssertion]);
+        });
+
+        it("has exit code 1 and fixes a file if not all rules can be fixed", () => {
+            const child = runESLint(["--fix", "--no-eslintrc", "--no-ignore", "--rule", "max-len: [2, 10]", tempFilePath]);
+            const exitCodeAssertion = assertExitCode(child, 1);
+            const outputFileAssertion = awaitExit(child).then(() => {
+                assert.strictEqual(fs.readFileSync(tempFilePath).toString(), expectedFixedText);
+            });
+
+            return Promise.all([exitCodeAssertion, outputFileAssertion]);
+        });
+
+        afterEach(() => {
+            fs.unlinkSync(tempFilePath);
+        });
+    });
+
     afterEach(() => {
 
         // Clean up all the processes after every test.

tests/fixtures/autofix-integration/left-pad-expected.js

@@ -0,0 +1,32 @@
+/* eslint dot-notation: 2 */
+/* eslint indent: [2, 2] */
+/* eslint no-extra-parens: 2 */
+/* eslint no-implicit-coercion: 2 */
+/* eslint no-whitespace-before-property: 2 */
+/* eslint quotes: [2, "single"] */
+/* eslint semi: 2 */
+/* eslint semi-spacing: 2 */
+/* eslint space-before-function-paren: 2 */
+
+/*
+* left-pad@0.0.3
+* WTFPL https://github.com/stevemao/left-pad/blob/aff6d744155a70b81f09effb8185a1564f348462/COPYING
+*/
+
+module.exports = leftpad;
+
+function leftpad (str, len, ch) {
+  str = String(str);
+
+  var i = -1;
+
+  ch || (ch = ' ');
+  len = len - str.length;
+
+
+  while (++i < len) {
+    str = ch + str;
+  }
+
+  return str;
+}

tests/fixtures/autofix-integration/left-pad.js

@@ -0,0 +1,32 @@
+/* eslint dot-notation: 2 */
+/* eslint indent: [2, 2] */
+/* eslint no-extra-parens: 2 */
+/* eslint no-implicit-coercion: 2 */
+/* eslint no-whitespace-before-property: 2 */
+/* eslint quotes: [2, "single"] */
+/* eslint semi: 2 */
+/* eslint semi-spacing: 2 */
+/* eslint space-before-function-paren: 2 */
+
+/*
+* left-pad@0.0.3
+* WTFPL https://github.com/stevemao/left-pad/blob/aff6d744155a70b81f09effb8185a1564f348462/COPYING
+*/
+
+module.exports = (leftpad)
+
+   function leftpad(str, len, ch) {
+  str = ("" + str);
+
+         var i = -1 ;
+
+  ch || (ch = " ");
+  len = (len - str  [  "length"])
+
+
+                   while (++i < len) {
+                  str = ch + str;
+						}
+
+  return str;
+}