6 calls to file_munge_filename()

file_save_upload in drupal/core/includes/file.inc
Saves file uploads to a new location.
NameMungingTest::testMungeIgnoreInsecure in drupal/core/modules/system/lib/Drupal/system/Tests/File/NameMungingTest.php
If the system.file.allow_insecure_uploads setting evaluates to true, the file should come out untouched, no matter how evil the filename.
NameMungingTest::testMungeIgnoreWhitelisted in drupal/core/modules/system/lib/Drupal/system/Tests/File/NameMungingTest.php
White listed extensions are ignored by file_munge_filename().
NameMungingTest::testMungeNullByte in drupal/core/modules/system/lib/Drupal/system/Tests/File/NameMungingTest.php
Tests munging with a null byte in the filename.
NameMungingTest::testMunging in drupal/core/modules/system/lib/Drupal/system/Tests/File/NameMungingTest.php
Create a file and munge/unmunge the name.
NameMungingTest::testUnMunge in drupal/core/modules/system/lib/Drupal/system/Tests/File/NameMungingTest.php
Ensure that unmunge gets your name back.