MDL-53140 forms: Added the float form element to the form API

lib/form/float.php

@@ -0,0 +1,187 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Float type form element
+ *
+ * Contains HTML class for a float type element
+ *
+ * @package   core_form
+ * @category  form
+ * @copyright 2019 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->libdir . '/form/text.php');
+
+/**
+ * Float type form element.
+ *
+ * This is preferred over the text element when working with float numbers, and takes care of the fact that different languages
+ * may use different symbols as the decimal separator.
+ * Using this element, submitted float numbers will be automatically translated from the localised format into the computer format,
+ * and vice versa when they are being displayed.
+ *
+ * @copyright 2019 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class MoodleQuickForm_float extends MoodleQuickForm_text {
+
+    /**
+     * MoodleQuickForm_float constructor.
+     *
+     * @param string $elementName (optional) name of the float field
+     * @param string $elementLabel (optional) float field label
+     * @param string $attributes (optional) Either a typical HTML attribute string or an associative array
+     */
+    public function __construct($elementName = null, $elementLabel = null, $attributes = null) {
+        parent::__construct($elementName, $elementLabel, $attributes);
+        $this->_type = 'float';
+    }
+
+    /**
+     * Called by HTML_QuickForm whenever form event is made on this element.
+     *
+     * @param string $event Name of event
+     * @param mixed $arg event arguments
+     * @param object $caller calling object
+     * @return bool
+     */
+    public function onQuickFormEvent($event, $arg, &$caller) {
+        switch ($event) {
+            case 'updateValue':
+                if ($value = $this->_findValue($caller->_constantValues)) {
+                    $value = $this->format_float($value);
+                }
+                if (null === $value) {
+                    $value = $this->_findValue($caller->_submitValues);
+                    if (null === $value) {
+                        if ($value = $this->_findValue($caller->_defaultValues)) {
+                            $value = $this->format_float($value);
+                        }
+                    }
+                }
+                if (null !== $value) {
+                    parent::setValue($value);
+                }
+                return true;
+            case 'createElement':
+                $caller->setType($arg[0], PARAM_RAW_TRIMMED);
+            default:
+                return parent::onQuickFormEvent($event, $arg, $caller);
+        }
+    }
+
+    /**
+     * Checks that the submitted value is a valid float number.
+     *
+     * @param string $value The localised float number that is submitted.
+     * @return string|null Validation error message or null.
+     */
+    public function validateSubmitValue($value) {
+        if (false === unformat_float($value, true)) {
+            return get_string('err_numeric', 'core_form');
+        }
+    }
+
+    /**
+     * Sets the value of the form element.
+     *
+     * @param string $value Default value of the form element
+     */
+    public function setValue($value) {
+        $value = $this->format_float($value);
+        parent::setValue($value);
+    }
+
+    /**
+     * Returns the value of the form element.
+     *
+     * @return false|float
+     */
+    public function getValue() {
+        $value = parent::getValue();
+        if ($value) {
+            $value = unformat_float($value, true);
+        }
+        return $value;
+    }
+
+    /**
+     * Returns a 'safe' element's value.
+     *
+     * @param  array   $submitValues array of submitted values to search
+     * @param  bool    $assoc whether to return the value as associative array
+     * @return mixed
+     */
+    public function exportValue(&$submitValues, $assoc = false) {
+        $value = $this->_findValue($submitValues);
+        if (null === $value) {
+            $value = $this->getValue();
+        } else if ($value) {
+            $value = unformat_float($value, true);
+        }
+        return $this->_prepareValue($value, $assoc);
+    }
+
+    /**
+     * Used by getFrozenHtml() to pass the element's value if _persistantFreeze is on.
+     *
+     * @return string
+     */
+    public function _getPersistantData() {
+        if (!$this->_persistantFreeze) {
+            return '';
+        } else {
+            $id = $this->getAttribute('id');
+            if (isset($id)) {
+                // Id of persistant input is different then the actual input.
+                $id = array('id' => $id . '_persistant');
+            } else {
+                $id = array();
+            }
+
+            return '<input' . $this->_getAttrString(array(
+                        'type'  => 'hidden',
+                        'name'  => $this->getAttribute('name'),
+                        'value' => $this->getAttribute('value')
+                    ) + $id) . ' />';
+        }
+    }
+
+    /**
+     * Given a float, prints it nicely.
+     * This function reserves the number of decimal places.
+     *
+     * @param float|null $value The float number to format
+     * @return string Localised float
+     */
+    private function format_float($value) {
+        if (is_numeric($value)) {
+            if ($value > 0) {
+                $decimals = strlen($value) - strlen(floor($value)) - 1;
+            } else {
+                $decimals = strlen($value) - strlen(ceil($value)) - 1;
+            }
+            $value = format_float($value, $decimals);
+        }
+        return $value;
+    }
+}

lib/form/tests/float_test.php

@@ -0,0 +1,99 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Unit tests for float form element.
+ *
+ * @package    core_form
+ * @category   test
+ * @copyright  2019 Shamim Rezaie <shamim@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->libdir . '/form/float.php');
+
+/**
+ * Unit tests for MoodleQuickForm_float
+ *
+ * Contains test cases for testing MoodleQuickForm_float
+ *
+ * @package    core_form
+ * @copyright  2019 Shamim Rezaie <shamim@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class core_form_float_testcase extends advanced_testcase {
+
+    /**
+     * Define a local decimal separator.
+     *
+     * It is not possible to directly change the result of get_string in
+     * a unit test. Instead, we create a language pack for language 'xx' in
+     * dataroot and make langconfig.php with the string we need to change.
+     * The example separator used here is 'X'.
+     */
+    protected function define_local_decimal_separator() {
+        global $SESSION, $CFG;
+
+        $SESSION->lang = 'xx';
+        $langconfig = "<?php\n\$string['decsep'] = 'X';";
+        $langfolder = $CFG->dataroot . '/lang/xx';
+        check_dir_exists($langfolder);
+        file_put_contents($langfolder . '/langconfig.php', $langconfig);
+    }
+
+    /**
+     * Testcase to check generated timestamp
+     */
+    public function test_exportValue() {
+        $element = new MoodleQuickForm_float('testel');
+
+        $value = ['testel' => 3.14];
+        $this->assertEquals(3.14, $element->exportValue($value));
+
+        $value = ['testel' => '3.14'];
+        $this->assertEquals(3.14, $element->exportValue($value));
+
+        $value = ['testel' => '-3.14'];
+        $this->assertEquals(-3.14, $element->exportValue($value));
+
+        $value = ['testel' => '3.14blah'];
+        $this->assertEquals(false, $element->exportValue($value));
+
+        $value = ['testel' => 'blah'];
+        $this->assertEquals(false, $element->exportValue($value));
+
+        // Tests with a localised decimal separator.
+        $this->define_local_decimal_separator();
+
+        $value = ['testel' => 3.14];
+        $this->assertEquals(3.14, $element->exportValue($value));
+
+        $value = ['testel' => '3X14'];
+        $this->assertEquals(3.14, $element->exportValue($value));
+
+        $value = ['testel' => '-3X14'];
+        $this->assertEquals(-3.14, $element->exportValue($value));
+
+        $value = ['testel' => '3X14blah'];
+        $this->assertEquals(false, $element->exportValue($value));
+
+        $value = ['testel' => 'blah'];
+        $this->assertEquals(false, $element->exportValue($value));
+    }
+}

lib/formslib.php

@@ -3241,6 +3241,7 @@ MoodleQuickForm::registerElementType('editor', "$CFG->libdir/form/editor.php", '
 MoodleQuickForm::registerElementType('filemanager', "$CFG->libdir/form/filemanager.php", 'MoodleQuickForm_filemanager');
 MoodleQuickForm::registerElementType('filepicker', "$CFG->libdir/form/filepicker.php", 'MoodleQuickForm_filepicker');
 MoodleQuickForm::registerElementType('filetypes', "$CFG->libdir/form/filetypes.php", 'MoodleQuickForm_filetypes');
+MoodleQuickForm::registerElementType('float', "$CFG->libdir/form/float.php", 'MoodleQuickForm_float');
 MoodleQuickForm::registerElementType('grading', "$CFG->libdir/form/grading.php", 'MoodleQuickForm_grading');
 MoodleQuickForm::registerElementType('group', "$CFG->libdir/form/group.php", 'MoodleQuickForm_group');
 MoodleQuickForm::registerElementType('header', "$CFG->libdir/form/header.php", 'MoodleQuickForm_header');

lib/upgrade.txt

@@ -48,6 +48,7 @@ is disabled).
 * The following functions have been updated to support the new usage:
     - make_pluginfile_url
     - file_rewrite_pluginfile_urls
+* New mform element 'float' handles localised floating point numbers.
 
 === 3.6 ===
 

theme/boost/templates/core_form/element-float-inline.mustache

@@ -0,0 +1 @@
+{{> core_form/element-text-inline }}

theme/boost/templates/core_form/element-float.mustache

@@ -0,0 +1 @@
+{{> core_form/element-text }}