Merge pull request #508 from ElonVolo/GitIgnoreFlagIgnores

Adding --gitignore flag

README.md

@@ -54,6 +54,8 @@ All options are also passed to the transformer, which means you can supply custo
   -h, --help                    print this help and exit
       --ignore-config=FILE ...  ignore files if they match patterns sourced from a configuration file (e.g. a .gitignore)
       --ignore-pattern=GLOB ...  ignore files that match a provided glob expression
+      --(no-)gitignore          adds entries the current directory's .gitignore file
+                                (default: false)
       --parser=babel|babylon|flow|ts|tsx  the parser to use for parsing the source files
                                           (default: babel)
       --parser-config=FILE      path to a JSON file containing a custom parser configuration for flow or babylon
@@ -216,14 +218,14 @@ __Example: specifying parser type string in the transform file__
 module.exports = function transformer(file, api, options) {
   const j = api.jscodeshift;
   const rootSource = j(file.source);
-  
+
   // whatever other code...
-  
+
   return rootSource.toSource();
 }
-  
+
 // use the flow parser
-module.exports.parser = 'flow'; 
+module.exports.parser = 'flow';
 ```
 
 __Example: specifying a custom parser object in the transform file__
@@ -233,9 +235,9 @@ __Example: specifying a custom parser object in the transform file__
 module.exports = function transformer(file, api, options) {
   const j = api.jscodeshift;
   const rootSource = j(file.source);
-  
+
   // whatever other code...
-  
+
   return rootSource.toSource();
 }
 
@@ -396,6 +398,40 @@ jscodeshift(ast).findIdentifiers().logNames();
 jscodeshift(ast).logNames(); // error, unless `ast` only consists of Identifier nodes
 ```
 
+### Ignoring files and directories
+
+
+Sometimes there are files and directories that you want to avoid running transforms on. For example, the node_modules/ directory, where the project's installed local npm packages reside, can introduce bugs if any files in it are accidentally transformed by jscodeshift.
+
+The simplest way to avoid many of these unwanted transforms is to pass jscodeshift the __--gitignore__ flag, which uses the glob patterns specified in your project’s .gitignore file to avoid transforming anything in directories such as node_modules/, dist/, etc. In most cases anything you want git to ignore you proabably are also going to want jscodeshift to ignore as well. _Please note that the .gitignore file use will be taken from the current working directory from which jscodeshift is being run._
+
+```
+jscodeshift --gitignore mytransform.js
+```
+
+For more custom ignore functionality, the __--ignore-pattern__ and the __--ignore-config__ arguments can be used.
+
+
+__--ignore-pattern__  takes a [.gitignore format](https://git-scm.com/docs/gitignore#_pattern_format) glob pattern that specifies file and directory patterns to ignore
+
+```
+jscodeshift --ignore-pattern="js_configuration_files/**/*” mytransform.js
+
+// More than one ignore
+jscodeshift --ignore-pattern="first_ignored_dir/**/*” -—ignore-pattern="second_ignored_dir/**/*” mytransform.js
+```
+
+__--ignore-config__ takes one or more paths to files containing lines with [.gitignore format](https://git-scm.com/docs/gitignore#_pattern_format) glob patterns.
+```
+
+// note: .gitignore is a random made-up filename extension for this example
+
+jscodeshift --ignore-config="MyIgnoreFile.gitignore" mytransform.js
+
+// More than one ignore file
+jscodeshift --ignore-pattern="first_ignore_file.gitignore” --ignore-pattern="second_ignore_file.gitignore” mytransform.js
+```
+
 ### Passing options to [recast]
 
 You may want to change some of the output settings (like setting `'` instead of `"`).

bin/__tests__/jscodeshift-test.js

@@ -20,6 +20,7 @@ const path = require('path');
 const temp = require('temp');
 const mkdirp = require('mkdirp');
 const testUtils = require('../../utils/testUtils');
+const {chdir} = require('process');
 
 const createTransformWith = testUtils.createTransformWith;
 const createTempFileWith = testUtils.createTempFileWith;
@@ -310,6 +311,48 @@ describe('jscodeshift CLI', () => {
       );
     });
 
+    it('sources ignore patterns from configuration file', () => {
+      const patterns = ['sub/dir/', '*-test.js'];
+      const gitignore = createTempFileWith(patterns.join('\n'), '.gitignore');
+      sources.push(createTempFileWith('subfile', 'sub/dir/file.js'));
+
+      return run(['-t', transform, '--ignore-config', gitignore].concat(sources)).then(
+        () => {
+          expect(readFile(sources[0]).toString()).toBe('transforma');
+          expect(readFile(sources[1]).toString()).toBe('a');
+          expect(readFile(sources[2]).toString()).toBe('subfile');
+        }
+      );
+    });
+
+    it('sources ignore patterns from a root directory\'s .gitignore file', () => {
+      // This test is a little different from the one above only in that we have
+      // to simulate automatically hitting up the .gitignore file from the current
+      // directory that the codeshift process is running from
+      const patterns = ['sub/dir/', '*-test.js'];
+      const gitignore = createTempFileWith(patterns.join('\n'), '.gitignore');
+      sources.push(createTempFileWith('subfile', 'sub/dir/file.js'));
+
+      // Make the temp directory with our test files the current working directory
+      let currPath = process.cwd();
+      let tempDirPath = path.dirname(sources[0]);
+      process.chdir(tempDirPath);;
+
+      return run(['-t', transform, '--gitignore'].concat(sources)).then(
+        () => {
+          expect(readFile(sources[0]).toString()).toBe('transforma');
+          expect(readFile(sources[1]).toString()).toBe('a');
+          expect(readFile(sources[2]).toString()).toBe('subfile');
+        }
+      )
+      .catch((err) => {
+        console.log(err);
+      })
+      .finally(() => {
+        process.chdir(currPath);
+      })
+    });
+
     it('accepts a list of configuration files', () => {
       const gitignore = createTempFileWith(['sub/dir/'].join('\n'), '.gitignore');
       const eslintignore = createTempFileWith(['**/*test.js', 'sourceA.js'].join('\n'), '.eslintignore');

src/Runner.js

@@ -168,9 +168,16 @@ function run(transformFile, paths, options) {
   const statsCounter = {};
   const startTime = process.hrtime();
 
+  ignores.add(options.ignoreSet);
   ignores.add(options.ignorePattern);
   ignores.addFromFile(options.ignoreConfig);
 
+  if (options.gitignore) {
+    let currDirectory = process.cwd();
+    let gitIgnorePath = path.join(currDirectory, '.gitignore');
+    ignores.addFromFile(gitIgnorePath);
+  }
+
   if (/^http/.test(transformFile)) {
     usedRemoteScript = true;
     return new Promise((resolve, reject) => {