Fixing Errors Automatically

Note: This documentation is for the phpcs-fixer branch only. Everything described here is still experimental.

PHP_CodeSniffer is able to fix many errors and warnings automatically. The diff report can be used to generate a diff that can be applied using the patch command. Alternatively, the PHP Code Beautifier and Fixer (phpcbf) can be used in place of phpcs to automatically generate and apply the diff for you.

Screen-based reports, such as the full, summary and source reports, provide information about how many errors and warnings are found. If any of the issues can be fixed automatically by phpcbf, an additional line of information will be printed:

$ phpcs /path/to/code/myfile.php

FILE: /path/to/code/myfile.php
--------------------------------------------------------------------------------
FOUND 5 ERRORS AFFECTING 4 LINES
--------------------------------------------------------------------------------
 2 | ERROR | Missing file doc comment
 3 | ERROR | TRUE, FALSE and NULL must be lowercase; expected "false" but found
   |       | "FALSE"
 5 | ERROR | Line indented incorrectly; expected at least 4 spaces, found 1
 8 | ERROR | Missing function doc comment
 8 | ERROR | Opening brace should be on a new line
--------------------------------------------------------------------------------
PHPCBF CAN FIX 2 OF THESE SNIFF VIOLATIONS AUTOMATICALLY
--------------------------------------------------------------------------------

Printing a Diff Report

The diff report is described here as it is not currently included in the main PHPCS release. It will be moved to the Reporting page at a late date.

PHP_CodeSniffer can output a diff file that can be applied using the patch command. The suggested changes will fix some of the sniff violations that are present in the sour code. To print a diff report, use the --report=diff command line argument. The output will look like this:

$ phpcs --report=diff /path/to/code

--- /path/to/code/file.php
+++ PHP_CodeSniffer
@@ -1,8 +1,8 @@
 <?php
 
-if ($foo === FALSE) {
+if ($foo === false) {
+    echo 'hi';
     echo 'hi';
- echo 'hi';
 }
 
 function foo() {

Diff reports are more easily used when output to a file. They can then be applied using the patch command:

$ phpcs --report-diff=/path/to/changes.diff /path/to/code
$ patch -p0 -ui /path/to/changes.diff
patching file /path/to/code/file.php

Using the PHP Code Beautifier and Fixer

To automatically fix as many sniff violations as possible, use the phpcbf command in place of the phpcs command. When using this command, you do not need to specify a report type. PHPCBF will automatically produce a diff file and apply it to your code:

$ phpcbf /path/to/code
Patched 1 files
Time: 35 ms, Memory: 5.00Mb

The source code is now ready for you to test and commit.