Add no-babelrc option in babel-node (#5621)

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| Q                        | A <!--(yes/no) -->
| ------------------------ | ---
| Patch: Bug Fix?          | 
| Major: Breaking Change?  | 
| Minor: New Feature?      | y
| Deprecations?            | 
| Spec Compliancy?         | 
| Tests Added/Pass?        | y/y
| Fixed Tickets            | #5616
| License                  | MIT
| Doc PR                   | <!-- if yes, add `[skip ci]` to your commit message to skip CI builds -->
| Dependency Changes       | 

<!-- Describe your changes below in as much detail as possible -->

Once merged I will make the corresponding documentation changes on the website (in a 7 branch)

packages/babel-cli/test/index.js

@@ -36,7 +36,9 @@ const readDir = function(loc, filter) {
 
 const saveInFiles = function(files) {
   // Place an empty .babelrc in each test so tests won't unexpectedly get to repo-level config.
-  outputFileSync(".babelrc", "{}");
+  if (!fs.existsSync(".babelrc")) {
+    outputFileSync(".babelrc", "{}");
+  }
 
   Object.keys(files).forEach(function(filename) {
     const content = files[filename];

packages/babel-node/src/_babel-node.js

@@ -22,6 +22,10 @@ function collect(value, previousValue): Array<string> {
 }
 
 program.option("-e, --eval [script]", "Evaluate script");
+program.option(
+  "--no-babelrc",
+  "Specify whether or not to use .babelrc and .babelignore files",
+);
 program.option("-r, --require [module]", "Require module");
 program.option("-p, --print [code]", "Evaluate script and print result");
 program.option(
@@ -47,6 +51,7 @@ program.usage("[options] [ -e script | script.js ] [arguments]");
 program.parse(process.argv);
 
 register({
+  babelrc: program.babelrc,
   extensions: program.extensions,
   ignore: program.ignore,
   only: program.only,

packages/babel-node/test/fixtures/babel-node/--no-babelrc/.babelrc

@@ -0,0 +1,3 @@
+{
+  "plugins": ["./logPlugin.js"]
+}

packages/babel-node/test/fixtures/babel-node/--no-babelrc/in-files/index.js

@@ -0,0 +1 @@
+console.log("foo");

packages/babel-node/test/fixtures/babel-node/--no-babelrc/in-files/logPlugin.js

@@ -0,0 +1,4 @@
+module.exports = function () {
+  console.log("Plugin was loaded, shouldn't appear due to --no-babelrc");
+  return {}
+}

packages/babel-node/test/fixtures/babel-node/--no-babelrc/options.json

@@ -0,0 +1,3 @@
+{
+  "args": ["--no-babelrc", "index"]
+}

packages/babel-node/test/fixtures/babel-node/--no-babelrc/stdout.txt

@@ -0,0 +1 @@
+foo