diff --git a/src/wp-includes/formatting.php b/src/wp-includes/formatting.php
index 51a1388dfd..bde523af0f 100644
--- a/src/wp-includes/formatting.php
+++ b/src/wp-includes/formatting.php
@@ -2465,17 +2465,63 @@ function force_balance_tags( $text ) {
// WP bug fix for LOVE <3 (and other situations with '<' before a number)
$text = preg_replace( '#<([0-9]{1})#', '<$1', $text );
- while ( preg_match( '/<(\/?[\w:]*)\s*([^>]*)>/', $text, $regex ) ) {
+ /**
+ * Matches supported tags
+ *
+ * To get the pattern as a string without the comments paste into a PHP
+ * REPL like `php -a`
+ *
+ * @see https://html.spec.whatwg.org/#elements-2
+ * @see https://w3c.github.io/webcomponents/spec/custom/#valid-custom-element-name
+ *
+ * @example
+ * ~# php -a
+ * php > $s = [paste copied contents of expression below including parentheses];
+ * php > echo $s;
+ *
+ * @type string
+ */
+ $tag_pattern = (
+ '#<' . // Start with an opening bracket.
+ '(/?)' . // Group 1 - If it's a closing tag it'll have a leading slash.
+ '(' . // Group 2 - tag name
+ // Custom element tags have more lenient rules than HTML tag names.
+ '(?:[a-z](?:[a-z0-9._]*)-(?:[a-z0-9._-]+)+)' .
+ '|' .
+ // Traditional tag rules approximate HTML tag names.
+ '(?:[\w:]+)' .
+ ')' .
+ '(?:' .
+ // We _either_ immediately close the tag with its '>' and have nothing here.
+ '\s*' .
+ '(/?)' . // Group 3 - "attributes" for empty tag
+ '|' .
+ // _or_ We must start with space characters to separate the tag name from the attributes (or whitespace).
+ '(\s+)' . // Group 4 - pre-attribute whitespace
+ '([^>]*)' . // Group 5 - attributes
+ ')' .
+ '>#' // End with a closing bracket.
+ );
+
+ while ( preg_match( $tag_pattern, $text, $regex ) ) {
+ $full_match = $regex[0];
+ $has_leading_slash = ! empty( $regex[1] );
+ $tag_name = $regex[2];
+ $tag = strtolower( $tag_name );
+ $is_single_tag = in_array( $tag, $single_tags, true );
+ $pre_attribute_ws = isset( $regex[4] ) ? $regex[4] : '';
+ $attributes = trim( isset( $regex[5] ) ? $regex[5] : $regex[3] );
+ $has_self_closer = '/' === substr( $attributes, -1 );
+
$newtext .= $tagqueue;
- $i = strpos( $text, $regex[0] );
- $l = strlen( $regex[0] );
+ $i = strpos( $text, $full_match );
+ $l = strlen( $full_match );
// clear the shifter
$tagqueue = '';
// Pop or Push
- if ( isset( $regex[1][0] ) && '/' == $regex[1][0] ) { // End Tag
- $tag = strtolower( substr( $regex[1], 1 ) );
+ if ( $has_leading_slash ) { // End Tag
// if too many closing tags
if ( $stacksize <= 0 ) {
$tag = '';
@@ -2501,21 +2547,16 @@ function force_balance_tags( $text ) {
$tag = '';
}
} else { // Begin Tag
- $tag = strtolower( $regex[1] );
-
// Tag Cleaning
-
- // If it's an empty tag "< >", do nothing
- if ( '' == $tag ) {
- // do nothing
- } elseif ( substr( $regex[2], -1 ) == '/' ) { // ElseIf it presents itself as a self-closing tag...
+ if ( $has_self_closer ) { // If it presents itself as a self-closing tag...
// ...but it isn't a known single-entity self-closing tag, then don't let it be treated as such and
// immediately close it with a closing tag (the tag will encapsulate no text as a result)
- if ( ! in_array( $tag, $single_tags ) ) {
- $regex[2] = trim( substr( $regex[2], 0, -1 ) ) . "> 0 && ! in_array( $tag, $nestable_tags ) && $tagstack[ $stacksize - 1 ] == $tag ) {
@@ -2526,12 +2567,12 @@ function force_balance_tags( $text ) {
}
// Attributes
- $attributes = $regex[2];
- if ( ! empty( $attributes ) && $attributes[0] != '>' ) {
- $attributes = ' ' . $attributes;
+ if ( $has_self_closer && $is_single_tag ) {
+ // we need some space - avoid
and prefer
+ $pre_attribute_ws = ' ';
}
- $tag = '<' . $tag . $attributes . '>';
+ $tag = '<' . $tag . $pre_attribute_ws . $attributes . '>';
//If already queuing a close tag, then put this tag on, too
if ( ! empty( $tagqueue ) ) {
$tagqueue .= $tag;
diff --git a/tests/phpunit/tests/formatting/balanceTags.php b/tests/phpunit/tests/formatting/balanceTags.php
index 783c320780..a533edbe36 100644
--- a/tests/phpunit/tests/formatting/balanceTags.php
+++ b/tests/phpunit/tests/formatting/balanceTags.php
@@ -37,6 +37,146 @@ class Tests_Formatting_BalanceTags extends WP_UnitTestCase {
);
}
+ function supported_traditional_tag_names() {
+ return array(
+ array( 'a' ),
+ array( 'div' ),
+ array( 'blockquote' ),
+ // HTML tag names can be CAPITALIZED and are case-insensitive
+ array( 'A' ),
+ array( 'dIv' ),
+ array( 'BLOCKQUOTE' ),
+ );
+ }
+
+ function supported_custom_element_tag_names() {
+ return array(
+ array( 'custom-element' ),
+ array( 'my-custom-element' ),
+ array( 'weekday-5-item' ),
+ array( 'a-big-old-tag-name' ),
+ array( 'with_underscores-and_the_dash' ),
+ );
+ }
+
+ function invalid_tag_names() {
+ return array(
+ array( '<0-day>inside', '<0-day>inside' ), // can't start with a number - handled by the "<3" "fix"
+ array( 'inside', 'inside' ), // custom elements cannot be uppercase
+ );
+ }
+
+ // These are valid custom elements but we don't support them yet.
+ // see https://w3c.github.io/webcomponents/spec/custom/#valid-custom-element-name
+ function unsupported_valid_tag_names() {
+ return array(
+ // we don't allow ending in a dash
+ array( 'inside' ),
+ // examples from the spec working document
+ array( 'math-α' ),
+ array( 'emotion-😍' ),
+ // UNICODE ranges
+ // middle dot
+ // 0x00b7
+ array( 'b-·' ),
+ // latin characters with accents/modifiers
+ // 0x00c0-0x00d6
+ // 0x00d8-0x00f6
+ array( 'a-À-Ó-Ý' ),
+ // 0x00f8-0x037d
+ array( 'a-ͳ' ),
+ // no 0x037e, which is a Greek semicolon
+ // 0x037f-0x1fff
+ array( 'a-Ფ' ),
+ // zero-width characters, probably never supported
+ // 0x200c-0x200d
+ array( 'a-to-my-left-is-a-zero-width-non-joiner-do-not-delete-it' ),
+ array( 'a-to-my-left-is-a-zero-width-joiner-do-not-delete-it' ),
+ // ties
+ // 0x203f-0x2040
+ array( 'under-‿-tie' ),
+ array( 'over-⁀-tie' ),
+ // 0x2170-0x218f
+ array( 'a-⁰' ),
+ array( 'a-⅀' ),
+ array( 'tag-ↀ-it' ),
+ // 0x2c00-0x2fef
+ array( 'a-Ⰰ' ),
+ array( 'b-ⴓ-c' ),
+ array( 'd-⽗' ),
+ // 0x3001-0xd7ff
+ array( 'a-、' ),
+ array( 'z-态' ),
+ array( 'a-送-䠺-ퟱ-' ),
+ // 0xf900-0xfdcf
+ array( 'a-豈' ),
+ array( 'my-切' ),
+ array( 'aﴀ-tag' ),
+ array( 'my-' ),
+ // 0xfdf0-0xfffd
+ array( 'a-ﷰ' ),
+ array( 'a---�' ), // warning; blank characters are in there
+ // extended ranges
+ // 0x10000-0xeffff
+ array( 'a-𐀀' ),
+ array( 'my-𝀀' ),
+ array( 'a𞀀-' ),
+ );
+ }
+
+ // These are invalid custom elements but we support them right now in order to keep the parser simpler
+ // see https://w3c.github.io/webcomponents/spec/custom/#valid-custom-element-name
+ function supported_invalid_tag_names() {
+ return array(
+ // reserved names for custom element
+ array( 'annotation-xml' ),
+ array( 'color-profile' ),
+ array( 'font-face' ),
+ array( 'font-face-src' ),
+ array( 'font-face-uri' ),
+ array( 'font-face-format' ),
+ array( 'font-face-name' ),
+ array( 'missing-glyph' ),
+ );
+ }
+
+ /**
+ * @dataProvider supported_traditional_tag_names
+ */
+ function test_detects_traditional_tag_names( $tag ) {
+ $normalized = strtolower( $tag );
+
+ $this->assertEquals( "<$normalized>inside", balanceTags( "<$tag>inside", true ) );
+ }
+
+ /**
+ * @dataProvider supported_custom_element_tag_names
+ */
+ function test_detects_supported_custom_element_tag_names( $tag ) {
+ $this->assertEquals( "<$tag>inside", balanceTags( "<$tag>inside", true ) );
+ }
+
+ /**
+ * @dataProvider invalid_tag_names
+ */
+ function test_ignores_invalid_tag_names( $input, $output ) {
+ $this->assertEquals( $output, balanceTags( $input, true ) );
+ }
+
+ /**
+ * @dataProvider unsupported_valid_tag_names
+ */
+ function test_ignores_unsupported_custom_tag_names( $tag ) {
+ $this->assertEquals( "<$tag>inside", balanceTags( "<$tag>inside", true ) );
+ }
+
+ /**
+ * @dataProvider supported_invalid_tag_names
+ */
+ function test_detects_supported_invalid_tag_names( $tag ) {
+ $this->assertEquals( "<$tag>inside", balanceTags( "<$tag>inside", true ) );
+ }
+
/**
* If a recognized valid single tag appears unclosed, it should get self-closed
*
@@ -68,12 +208,15 @@ class Tests_Formatting_BalanceTags extends WP_UnitTestCase {
'',
'',
'',
+ '',
);
$expected = array(
'',
'',
'',
'',
+ // Valid tags are transformed to lowercase.
+ '',
);
foreach ( $inputs as $key => $input ) {
@@ -221,4 +364,68 @@ class Tests_Formatting_BalanceTags extends WP_UnitTestCase {
}
}
+ /**
+ * Get custom element data.
+ *
+ * @return array Data.
+ */
+ public function data_custom_elements() {
+ return array(
+ // Valid custom element tags.
+ array(
+ '',
+ '',
+ ),
+ array(
+ 'Test',
+ 'Test',
+ ),
+ array(
+ 'Test',
+ 'Test',
+ ),
+ array(
+ 'Test',
+ 'Test',
+ ),
+ array(
+ 'Test',
+ 'Test',
+ ),
+ array(
+ '',
+ '',
+ ),
+ array(
+ '',
+ '',
+ ),
+ // Invalid (or at least temporarily unsupported) custom element tags.
+ array(
+ 'Test',
+ 'Test',
+ ),
+ array(
+ 'Test',
+ 'Test',
+ ),
+ array(
+ '<--->Test',
+ '<--->Test',
+ ),
+ );
+ }
+
+ /**
+ * Test custom elements.
+ *
+ * @ticket 47014
+ * @dataProvider data_custom_elements
+ *
+ * @param string $source Source.
+ * @param string $expected Expected.
+ */
+ public function test_custom_elements( $source, $expected ) {
+ $this->assertEquals( $expected, balanceTags( $source, true ) );
+ }
}