From: Sumit Asthana <asthana.sumit23@gmail.com>
Date: Tue, 23 Dec 2014 21:34:36 +0000 (+0530)
Subject: Database::makeList() : Handle NULL when building 'IN' clause
X-Git-Tag: 1.31.0-rc.0~12812^2
X-Git-Url: https://git.cyclocoop.org/%7B%24www_url%7Dadmin/compta/banques/?a=commitdiff_plain;h=26235c73376b87fe1fc3e6151e86cf071b705bba;p=lhc%2Fweb%2Fwiklou.git

Database::makeList() : Handle NULL when building 'IN' clause

Amends to Database::makeList() to check if 'NULL' is present in array while
building IN clause. Presently a NULL in array intended to build IN clause, is
treated as a usual value. This creates
problem:https://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html#function_in
Therefore null is appended at the end of the IN clause as " $field IS NULL"
rather than within the IN clause.
DatabaseSQLTest.php: Some test cases added for the modified behaviour.

Bug: T50853
Change-Id: Ic255c37e9702fd44d8173027ab8036ddc48f9d2e
---

diff --git a/RELEASE-NOTES-1.25 b/RELEASE-NOTES-1.25
index 4a6ee94750..4e195c5a6f 100644
--- a/RELEASE-NOTES-1.25
+++ b/RELEASE-NOTES-1.25
@@ -118,6 +118,7 @@ production.
 * The Special:WhatLinksHere page linked from 'Number of redirects to this page'
   on action=info about a file page does not list file links anymore.
 * (T78637) Search bar is not autofocused unless it is empty so that proper scrolling using arrow keys is possible.
+* (T50853) Database::makeList() modified to handle 'NULL' separately when building IN clause
 
 === Action API changes in 1.25 ===
 * (T67403) XML tag highlighting is now only performed for formats
diff --git a/includes/db/Database.php b/includes/db/Database.php
index 7938ce673a..0b022d139e 100644
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -2160,16 +2160,36 @@ abstract class DatabaseBase implements IDatabase {
 			} elseif ( ( $mode == LIST_SET ) && is_numeric( $field ) ) {
 				$list .= "$value";
 			} elseif ( ( $mode == LIST_AND || $mode == LIST_OR ) && is_array( $value ) ) {
-				if ( count( $value ) == 0 ) {
+				// Remove null from array to be handled separately if found
+				$includeNull = false;
+				foreach ( array_keys( $value, null, true ) as $nullKey ) {
+					$includeNull = true;
+					unset( $value[$nullKey] );
+				}
+				if ( count( $value ) == 0 && !$includeNull ) {
 					throw new MWException( __METHOD__ . ": empty input for field $field" );
-				} elseif ( count( $value ) == 1 ) {
-					// Special-case single values, as IN isn't terribly efficient
-					// Don't necessarily assume the single key is 0; we don't
-					// enforce linear numeric ordering on other arrays here.
-					$value = array_values( $value );
-					$list .= $field . " = " . $this->addQuotes( $value[0] );
+				} elseif ( count( $value ) == 0 ) {
+					// only check if $field is null
+					$list .= "$field IS NULL";
 				} else {
-					$list .= $field . " IN (" . $this->makeList( $value ) . ") ";
+					// IN clause contains at least one valid element
+					if ( $includeNull ) {
+						// Group subconditions to ensure correct precedence
+						$list .= '(';
+					}
+					if ( count( $value ) == 1 ) {
+						// Special-case single values, as IN isn't terribly efficient
+						// Don't necessarily assume the single key is 0; we don't
+						// enforce linear numeric ordering on other arrays here.
+						$value = array_values( $value );
+						$list .= $field . " = " . $this->addQuotes( $value[0] );
+					} else {
+						$list .= $field . " IN (" . $this->makeList( $value ) . ") ";
+					}
+					// if null present in array, append IS NULL
+					if ( $includeNull ) {
+						$list .= " OR $field IS NULL)";
+					}
 				}
 			} elseif ( $value === null ) {
 				if ( $mode == LIST_AND || $mode == LIST_OR ) {
diff --git a/tests/phpunit/includes/db/DatabaseSQLTest.php b/tests/phpunit/includes/db/DatabaseSQLTest.php
index 9d4765d749..b13751f360 100644
--- a/tests/phpunit/includes/db/DatabaseSQLTest.php
+++ b/tests/phpunit/includes/db/DatabaseSQLTest.php
@@ -755,6 +755,16 @@ class DatabaseSQLTest extends MediaWikiTestCase {
 				LIST_AND,
 				"field IS NULL AND (field2 != 'value2')"
 			),
+			array(
+				array( 'field' => array( 'value', null, 'value2' ), 'field2' => 'value2' ),
+				LIST_AND,
+				"(field IN ('value','value2')  OR field IS NULL) AND field2 = 'value2'"
+			),
+			array(
+				array( 'field' => array( null ), 'field2' => null ),
+				LIST_AND,
+				"field IS NULL AND field2 IS NULL"
+			),
 			array(
 				array( 'field' => 'value', 'field2' => 'value2' ),
 				LIST_OR,
@@ -770,6 +780,11 @@ class DatabaseSQLTest extends MediaWikiTestCase {
 				LIST_OR,
 				"field IN ('value','value2')  OR field2 = 'value'"
 			),
+			array(
+				array( 'field' => array( null, 'value', null, 'value2' ), "field2 != 'value2'" ),
+				LIST_OR,
+				"(field IN ('value','value2')  OR field IS NULL) OR (field2 != 'value2')"
+			),
 			array(
 				array( 'field' => 'value', 'field2' => 'value2' ),
 				LIST_SET,