--- /dev/null
+<?php
+
+namespace Drupal\Component\Render;
+
+use Drupal\Component\Utility\Html;
+use Drupal\Component\Utility\Unicode;
+use Drupal\Component\Utility\UrlHelper;
+
+/**
+ * Formats a string for HTML display by replacing variable placeholders.
+ *
+ * When cast to a string, this object replaces variable placeholders in the
+ * string with the arguments passed in during construction and escapes the
+ * values so they can be safely displayed as HTML. See the documentation of
+ * \Drupal\Component\Render\FormattableMarkup::placeholderFormat() for details
+ * on the supported placeholders and how to use them securely. Incorrect use of
+ * this class can result in security vulnerabilities.
+ *
+ * In most cases, you should use TranslatableMarkup or PluralTranslatableMarkup
+ * rather than this object, since they will translate the text (on
+ * non-English-only sites) in addition to formatting it. Variables concatenated
+ * without the insertion of language-specific words or punctuation are some
+ * examples where translation is not applicable and using this class directly
+ * directly is appropriate.
+ *
+ * This class is designed for formatting messages that are mostly text, not as
+ * an HTML template language. As such:
+ * - The passed in string should contain no (or minimal) HTML.
+ * - Variable placeholders should not be used within the "<" and ">" of an
+ * HTML tag, such as in HTML attribute values. This would be a security
+ * risk. Examples:
+ * @code
+ * // Insecure (placeholder within "<" and ">"):
+ * $this->placeholderFormat('<@variable>text</@variable>', ['@variable' => $variable]);
+ * // Insecure (placeholder within "<" and ">"):
+ * $this->placeholderFormat('<a @variable>link text</a>', ['@variable' => $variable]);
+ * // Insecure (placeholder within "<" and ">"):
+ * $this->placeholderFormat('<a title="@variable">link text</a>', ['@variable' => $variable]);
+ * @endcode
+ * Only the "href" attribute is supported via the special ":variable"
+ * placeholder, to allow simple links to be inserted:
+ * @code
+ * // Secure (usage of ":variable" placeholder for href attribute):
+ * $this->placeholderFormat('<a href=":variable">link text</a>', [':variable' , $variable]);
+ * // Secure (usage of ":variable" placeholder for href attribute):
+ * $this->placeholderFormat('<a href=":variable" title="static text">link text</a>', [':variable' => $variable]);
+ * // Insecure (the "@variable" placeholder does not filter dangerous
+ * // protocols):
+ * $this->placeholderFormat('<a href="@variable">link text</a>', ['@variable' => $variable]);
+ * // Insecure ("@variable" placeholder within "<" and ">"):
+ * $this->placeholderFormat('<a href=":url" title="@variable">link text</a>', [':url' => $url, '@variable' => $variable]);
+ * @endcode
+ * To build non-minimal HTML, use an HTML template language such as Twig,
+ * rather than this class.
+ *
+ * @ingroup sanitization
+ *
+ * @see \Drupal\Core\StringTranslation\TranslatableMarkup
+ * @see \Drupal\Core\StringTranslation\PluralTranslatableMarkup
+ * @see \Drupal\Component\Render\FormattableMarkup::placeholderFormat()
+ */
+class FormattableMarkup implements MarkupInterface, \Countable {
+
+ /**
+ * The arguments to replace placeholders with.
+ *
+ * @var array
+ */
+ protected $arguments = [];
+
+ /**
+ * Constructs a new class instance.
+ *
+ * @param string $string
+ * A string containing placeholders. The string itself will not be escaped,
+ * any unsafe content must be in $args and inserted via placeholders.
+ * @param array $arguments
+ * An array with placeholder replacements, keyed by placeholder. See
+ * \Drupal\Component\Render\FormattableMarkup::placeholderFormat() for
+ * additional information about placeholders.
+ *
+ * @see \Drupal\Component\Render\FormattableMarkup::placeholderFormat()
+ */
+ public function __construct($string, array $arguments) {
+ $this->string = (string) $string;
+ $this->arguments = $arguments;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function __toString() {
+ return static::placeholderFormat($this->string, $this->arguments);
+ }
+
+ /**
+ * Returns the string length.
+ *
+ * @return int
+ * The length of the string.
+ */
+ public function count() {
+ return Unicode::strlen($this->string);
+ }
+
+ /**
+ * Returns a representation of the object for use in JSON serialization.
+ *
+ * @return string
+ * The safe string content.
+ */
+ public function jsonSerialize() {
+ return $this->__toString();
+ }
+
+ /**
+ * Replaces placeholders in a string with values.
+ *
+ * @param string $string
+ * A string containing placeholders. The string itself is expected to be
+ * safe and correct HTML. Any unsafe content must be in $args and
+ * inserted via placeholders.
+ * @param array $args
+ * An associative array of replacements. Each array key should be the same
+ * as a placeholder in $string. The corresponding value should be a string
+ * or an object that implements
+ * \Drupal\Component\Render\MarkupInterface. The value replaces the
+ * placeholder in $string. Sanitization and formatting will be done before
+ * replacement. The type of sanitization and formatting depends on the first
+ * character of the key:
+ * - @variable: When the placeholder replacement value is:
+ * - A string, the replaced value in the returned string will be sanitized
+ * using \Drupal\Component\Utility\Html::escape().
+ * - A MarkupInterface object, the replaced value in the returned string
+ * will not be sanitized.
+ * - A MarkupInterface object cast to a string, the replaced value in the
+ * returned string be forcibly sanitized using
+ * \Drupal\Component\Utility\Html::escape().
+ * @code
+ * $this->placeholderFormat('This will force HTML-escaping of the replacement value: @text', ['@text' => (string) $safe_string_interface_object));
+ * @endcode
+ * Use this placeholder as the default choice for anything displayed on
+ * the site, but not within HTML attributes, JavaScript, or CSS. Doing so
+ * is a security risk.
+ * - %variable: Use when the replacement value is to be wrapped in <em>
+ * tags.
+ * A call like:
+ * @code
+ * $string = "%output_text";
+ * $arguments = ['%output_text' => 'text output here.'];
+ * $this->placeholderFormat($string, $arguments);
+ * @endcode
+ * makes the following HTML code:
+ * @code
+ * <em class="placeholder">text output here.</em>
+ * @endcode
+ * As with @variable, do not use this within HTML attributes, JavaScript,
+ * or CSS. Doing so is a security risk.
+ * - :variable: Return value is escaped with
+ * \Drupal\Component\Utility\Html::escape() and filtered for dangerous
+ * protocols using UrlHelper::stripDangerousProtocols(). Use this when
+ * using the "href" attribute, ensuring the attribute value is always
+ * wrapped in quotes:
+ * @code
+ * // Secure (with quotes):
+ * $this->placeholderFormat('<a href=":url">@variable</a>', [':url' => $url, '@variable' => $variable]);
+ * // Insecure (without quotes):
+ * $this->placeholderFormat('<a href=:url>@variable</a>', [':url' => $url, '@variable' => $variable]);
+ * @endcode
+ * When ":variable" comes from arbitrary user input, the result is secure,
+ * but not guaranteed to be a valid URL (which means the resulting output
+ * could fail HTML validation). To guarantee a valid URL, use
+ * Url::fromUri($user_input)->toString() (which either throws an exception
+ * or returns a well-formed URL) before passing the result into a
+ * ":variable" placeholder.
+ *
+ * @return string
+ * A formatted HTML string with the placeholders replaced.
+ *
+ * @ingroup sanitization
+ *
+ * @see \Drupal\Core\StringTranslation\TranslatableMarkup
+ * @see \Drupal\Core\StringTranslation\PluralTranslatableMarkup
+ * @see \Drupal\Component\Utility\Html::escape()
+ * @see \Drupal\Component\Utility\UrlHelper::stripDangerousProtocols()
+ * @see \Drupal\Core\Url::fromUri()
+ */
+ protected static function placeholderFormat($string, array $args) {
+ // Transform arguments before inserting them.
+ foreach ($args as $key => $value) {
+ switch ($key[0]) {
+ case '@':
+ // Escape if the value is not an object from a class that implements
+ // \Drupal\Component\Render\MarkupInterface, for example strings will
+ // be escaped.
+ // Strings that are safe within HTML fragments, but not within other
+ // contexts, may still be an instance of
+ // \Drupal\Component\Render\MarkupInterface, so this placeholder type
+ // must not be used within HTML attributes, JavaScript, or CSS.
+ $args[$key] = static::placeholderEscape($value);
+ break;
+
+ case ':':
+ // Strip URL protocols that can be XSS vectors.
+ $value = UrlHelper::stripDangerousProtocols($value);
+ // Escape unconditionally, without checking whether the value is an
+ // instance of \Drupal\Component\Render\MarkupInterface. This forces
+ // characters that are unsafe for use in an "href" HTML attribute to
+ // be encoded. If a caller wants to pass a value that is extracted
+ // from HTML and therefore is already HTML encoded, it must invoke
+ // \Drupal\Component\Render\OutputStrategyInterface::renderFromHtml()
+ // on it prior to passing it in as a placeholder value of this type.
+ // @todo Add some advice and stronger warnings.
+ // https://www.drupal.org/node/2569041.
+ $args[$key] = Html::escape($value);
+ break;
+
+ case '%':
+ // Similarly to @, escape non-safe values. Also, add wrapping markup
+ // in order to render as a placeholder. Not for use within attributes,
+ // per the warning above about
+ // \Drupal\Component\Render\MarkupInterface and also due to the
+ // wrapping markup.
+ $args[$key] = '<em class="placeholder">' . static::placeholderEscape($value) . '</em>';
+ break;
+
+ default:
+ // We do not trigger an error for placeholder that start with an
+ // alphabetic character.
+ // @todo https://www.drupal.org/node/2807743 Change to an exception
+ // and always throw regardless of the first character.
+ if (!ctype_alpha($key[0])) {
+ // We trigger an error as we may want to introduce new placeholders
+ // in the future without breaking backward compatibility.
+ trigger_error('Invalid placeholder (' . $key . ') in string: ' . $string, E_USER_ERROR);
+ }
+ elseif (strpos($string, $key) !== FALSE) {
+ trigger_error('Invalid placeholder (' . $key . ') in string: ' . $string, E_USER_DEPRECATED);
+ }
+ // No replacement possible therefore we can discard the argument.
+ unset($args[$key]);
+ break;
+ }
+ }
+
+ return strtr($string, $args);
+ }
+
+ /**
+ * Escapes a placeholder replacement value if needed.
+ *
+ * @param string|\Drupal\Component\Render\MarkupInterface $value
+ * A placeholder replacement value.
+ *
+ * @return string
+ * The properly escaped replacement value.
+ */
+ protected static function placeholderEscape($value) {
+ return $value instanceof MarkupInterface ? (string) $value : Html::escape($value);
+ }
+
+}
projects / yaffs-website / blobdiff