Matching a search with a regular expression and four lines of context - php

Question

For example, I have this kind of code:
<?php
/**
* Order
*
* The WooCommerce order class handles order data.
*
* #class WC_Order
* #version 1.6.4
* #package WooCommerce/Classes
* #category Class
* #author WooThemes
*/
class WC_Order {
/** #public int Order (post) ID */
public $id;
/** #public string Order status. */
public $status;
/** #public string Order date (placed). */
public $order_date;
/** #public string Order date (paid). */
public $modified_date;
/** #public string Note added by the customer. */
public $customer_note;
/** #public array Order (post) meta/custom fields. */
public $order_custom_fields;
global $wpdb, $woocommerce;
if ( empty( $type ) )
$type = array( 'line_item' );
if ( ! is_array( $type ) )
$type = array( $type );
$items = $this->get_items( $type );
$count = 0;
foreach ( $items as $item ) {
if ( ! empty( $item['qty'] ) )
$count += $item['qty'];
else
$count ++;
}
return apply_filters( 'woocommerce_get_item_count', $count, $type, $this );
}
/**
* Return an array of fees within this order.
*
* #access public
* #return array
*/
public function get_fees() {
return $this->get_items( 'fee' );
}
/**
* Return an array of taxes within this order.
*
* #access public
* #return void
*/
public function get_taxes() {
return $this->get_items( 'tax' );
}
/**
* Get taxes, merged by code, formatted ready for output.
*
* #access public
* #return void
*/
public function get_tax_totals() {
$taxes = $this->get_items( 'tax' );
$tax_totals = array();
foreach ( $taxes as $key => $tax ) {
$code = $tax[ 'name' ];
if ( ! isset( $tax_totals[ $code ] ) ) {
$tax_totals[ $code ] = new stdClass();
$tax_totals[ $code ]->amount = 0;
}
$tax_totals[ $code ]->is_compound = $tax[ 'compound' ];
$tax_totals[ $code ]->label = isset( $tax[ 'label' ] ) ? $tax[ 'label' ] : $tax[ 'name' ];
$tax_totals[ $code ]->amount += $tax[ 'tax_amount' ] + $tax[ 'shipping_tax_amount' ];
$tax_totals[ $code ]->formatted_amount = woocommerce_price( $tax_totals[ $code ]->amount );
}
return apply_filters( 'woocommerce_order_tax_totals', $tax_totals, $this );
}
/**
* has_meta function for order items.
*
* #access public
* #return array of meta data
*/
public function has_meta( $order_item_id ) {
global $wpdb;
return $wpdb->get_results( $wpdb->prepare("SELECT meta_key, meta_value, meta_id, order_item_id
FROM {$wpdb->prefix}woocommerce_order_itemmeta WHERE order_item_id = %d
ORDER BY meta_key,meta_id", absint( $order_item_id ) ), ARRAY_A );
}
/**
* Get order item meta.
*
* #access public
* #param mixed $item_id
* #param string $key (default: '')
* #param bool $single (default: false)
* #return void
*/
public function get_item_meta( $order_item_id, $key = '', $single = false ) {
return get_metadata( 'order_item', $order_item_id, $key, $single );
}
I want to match all Wordpress hooks: "do_action" and "apply_filters" with three options:
apply_filters( 'woocommerce_order_tax_totals', $tax_totals, $this ), file, line number
An example of what i'm trying to do can be seen here:
http://etivite.com/api-hooks/buddypress/trigger/apply_filters/bp_get_total_mention_count_for_user/
http://adambrown.info/p/wp_hooks/hook/activated_plugin?version=3.6&file=wp-admin/includes/plugin.php
I did try to pull something out but with no success:
<?php
$path = $_SERVER['DOCUMENT_ROOT'] . '/wp-content/plugins/iphorm-form-builder';
foreach (new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path)) as $filename) {
if (substr($filename, -3) == 'php') {
$file = file($filename);
if ($file !== false) {
$matches1 = preg_grep( '/do_action\((.+)\);/', $file);
$matches2 = preg_grep( '/apply_filters\((.+)\);/', $file );
$arr = array_filter(array_merge($matches1, $matches2));
$out = '';
echo "found in $filename:";
echo "<pre>";
foreach ($arr as $key => $value) {
$out .= $file[$key-2];
$out .= $file[$key-1];
$out .= $file[$key];
$out .= $file[$key+1];
$out .= $file[$key+2];
}
echo htmlentities($out);
echo "</pre>";
} else {
echo "failed reading to array";
}
}
}

Answer 1

This can be done very simply by taking advantage of built-in shell commands.
<?php
$path = $_SERVER['DOCUMENT_ROOT'] . '/wp-content/plugins/iphorm-form-builder';
foreach (new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path)) as $filename) {
if (substr($filename, -3) == 'php') {
$context = shell_exec('grep -H -n -C4 do_action ' . escapeshellarg($filename));
if (!empty($context)) {
echo "found in $filename:";
echo "<pre>";
echo htmlentities($context);
echo "</pre>";
} else {
echo "failed reading to array";
}
}
}
Relevant documentation:
php shell_exec
Execute command via shell and return the complete output as a string
php escapeshellarg
Escape a string to be used as a shell argument
bash grep
Grep searches the named input FILEs (or standard input if no files are
named, or the file name - is given) for lines containing a match to the
given PATTERN. By default, grep prints the matching lines.
-C NUM, --context=NUM
Print NUM lines of output context. Places a line containing --
between contiguous groups of matches.
-H, --with-filename
Print the filename for each match.
-n, --line-number
Prefix each line of output with the line number within its input
file.
Edit
Depending on how many directories and files you have in your project, it may not be performant. You're basically creating a new process in a new shell for each file. That's not great. If you'd rather get a big dump of data and parse it out later, do this instead:
<?php
$path = $_SERVER['DOCUMENT_ROOT'] . '/wp-content/plugins/iphorm-form-builder';
$grep = shell_exec('grep --include=*.php -RHn -C4 do_action ' . escapeshellarg($path));
$matches = explode("\n--\n", $grep);
if (empty($matches)) {
echo "failed reading to array";
}
else {
foreach ($matches as $match) {
echo "<pre>";
echo htmlentities($match);
echo "</pre>";
}
}

Answer 2

You don't need to loop through file data line by line. Just read the data in a variable and apply regex:
$data = file_get_contents( $filename );
if (preg_match_all(
'~((?:[^\n]*\n){0,4}) *do_action\s*\(\s*([^)]+)\s*\)\s*;[^\n]*\n((?:[^\n]*\n){0,4})~',
$data, $arr)) {
// match found, now dump the results
// $arr[1] will print 4 lines before the match
// $arr[2] will print function arguments for do_action
// $arr[3] will print 4 lines after the match
print_r($arr);
}

Answer 3

This can not be done by regular expressions alone given the limitations of PHP's regular expression engine. Specifically, and it came as a surprise to me, you can not have variable length look behinds.
The reason you need look behinds is if you had the occurrence of do_action or apply_filters on consecutive lines, then the first match will prevent the second match if you had no look aheads, and even if you use look aheads, there is no way to get the previous two rows of the second match without the look behinds. Not to mention I don't even know if you can even include the contents of a look around assertion in the result.
This solution creates a regular expression to find the lines in which the function occurs, and then uses two more regexes to find the lines before and after. I took care to watch out for the start and end of file when designing the regexes.
$offset = 0;
while (preg_match('/^.*?(?:apply_filters|do_action)\s*\(.+?\)\s*;.*(?:\n\r|\n|\r|$)/m', $file, $match, PREG_OFFSET_CAPTURE, $offset))
{
$index = $match[0][1];
$offset = $index + strlen($match[0][0]);
$hasBefore = preg_match('/(?:.*(?:\n\r|\n|\r).*$)|[^\n\r].*$/',
substr($file, 0, $index), $beforeMatch);
$hasAfter = preg_match('/^(?:.*(?:\n\r|\n|\r|$)){0,2}/',
substr($file, $offset), $afterMatch);
if ($hasBefore) print_r($beforeMatch);
print_r($match[0][0]);
if ($hasAfter) print_r($afterMatch);
}
phpFiddle
This only displays two lines before and two lines after. You can use repetition if you want more, but it appears to me from the attempted solution that this was what the o.p. really wanted.