.length;
}
+ /**
+ * Calculate the character length of a string (accounting for UTF-16 surrogates).
+ *
+ * @param {string} str
+ * @return {number}
+ */
+ function codePointLength( str ) {
+ return str
+ // Low surrogate + high surrogate pairs represent one character (codepoint) each
+ .replace( /[\uD800-\uDBFF][\uDC00-\uDFFF]/g, '*' )
+ .length;
+ }
+
// Like String#charAt, but return the pair of UTF-16 surrogates for characters outside of BMP.
function codePointAt( string, offset, backwards ) {
// We don't need to check for offsets at the beginning or end of string,
}
}
- /**
- * Utility function to trim down a string, based on byteLimit
- * and given a safe start position. It supports insertion anywhere
- * in the string, so "foo" to "fobaro" if limit is 4 will result in
- * "fobo", not "foba". Basically emulating the native maxlength by
- * reconstructing where the insertion occurred.
- *
- * @param {string} safeVal Known value that was previously returned by this
- * function, if none, pass empty string.
- * @param {string} newVal New value that may have to be trimmed down.
- * @param {number} byteLimit Number of bytes the value may be in size.
- * @param {Function} [fn] Function to call on the string before assessing the length.
- * @return {Object}
- * @return {string} return.newVal
- * @return {boolean} return.trimmed
- */
- function trimByteLength( safeVal, newVal, byteLimit, fn ) {
+ function trimLength( safeVal, newVal, length, lengthFn ) {
var startMatches, endMatches, matchesLen, inpParts, chopOff, oldChar, newChar,
oldVal = safeVal;
// Run the hook if one was provided, but only on the length
// assessment. The value itself is not to be affected by the hook.
- if ( byteLength( fn ? fn( newVal ) : newVal ) <= byteLimit ) {
+ if ( lengthFn( newVal ) <= length ) {
// Limit was not reached, just remember the new value
// and let the user continue.
return {
// Chop off characters from the end of the "inserted content" string
// until the limit is statisfied.
- if ( fn ) {
- // stop, when there is nothing to slice - T43450
- while ( byteLength( fn( inpParts.join( '' ) ) ) > byteLimit && inpParts[ 1 ].length > 0 ) {
- // Do not chop off halves of surrogate pairs
- chopOff = /[\uD800-\uDBFF][\uDC00-\uDFFF]$/.test( inpParts[ 1 ] ) ? 2 : 1;
- inpParts[ 1 ] = inpParts[ 1 ].slice( 0, -chopOff );
- }
- } else {
- while ( byteLength( inpParts.join( '' ) ) > byteLimit ) {
- // Do not chop off halves of surrogate pairs
- chopOff = /[\uD800-\uDBFF][\uDC00-\uDFFF]$/.test( inpParts[ 1 ] ) ? 2 : 1;
- inpParts[ 1 ] = inpParts[ 1 ].slice( 0, -chopOff );
- }
+ // Make sure to stop when there is nothing to slice (T43450).
+ while ( lengthFn( inpParts.join( '' ) ) > length && inpParts[ 1 ].length > 0 ) {
+ // Do not chop off halves of surrogate pairs
+ chopOff = /[\uD800-\uDBFF][\uDC00-\uDFFF]$/.test( inpParts[ 1 ] ) ? 2 : 1;
+ inpParts[ 1 ] = inpParts[ 1 ].slice( 0, -chopOff );
}
return {
newVal: inpParts.join( '' ),
- // For pathological fn() that always returns a value longer than the limit, we might have
+ // For pathological lengthFn() that always returns a length greater than the limit, we might have
// ended up not trimming - check for this case to avoid infinite loops
trimmed: newVal !== inpParts.join( '' )
};
}
+ /**
+ * Utility function to trim down a string, based on byteLimit
+ * and given a safe start position. It supports insertion anywhere
+ * in the string, so "foo" to "fobaro" if limit is 4 will result in
+ * "fobo", not "foba". Basically emulating the native maxlength by
+ * reconstructing where the insertion occurred.
+ *
+ * @param {string} safeVal Known value that was previously returned by this
+ * function, if none, pass empty string.
+ * @param {string} newVal New value that may have to be trimmed down.
+ * @param {number} byteLimit Number of bytes the value may be in size.
+ * @param {Function} [filterFn] Function to call on the string before assessing the length.
+ * @return {Object}
+ * @return {string} return.newVal
+ * @return {boolean} return.trimmed
+ */
+ function trimByteLength( safeVal, newVal, byteLimit, filterFn ) {
+ var lengthFn;
+ if ( filterFn ) {
+ lengthFn = function ( val ) {
+ return byteLength( filterFn( val ) );
+ };
+ } else {
+ lengthFn = byteLength;
+ }
+
+ return trimLength( safeVal, newVal, byteLimit, lengthFn );
+ }
+
+ /**
+ * Utility function to trim down a string, based on codePointLimit
+ * and given a safe start position. It supports insertion anywhere
+ * in the string, so "foo" to "fobaro" if limit is 4 will result in
+ * "fobo", not "foba". Basically emulating the native maxlength by
+ * reconstructing where the insertion occurred.
+ *
+ * @param {string} safeVal Known value that was previously returned by this
+ * function, if none, pass empty string.
+ * @param {string} newVal New value that may have to be trimmed down.
+ * @param {number} codePointLimit Number of characters the value may be in size.
+ * @param {Function} [filterFn] Function to call on the string before assessing the length.
+ * @return {Object}
+ * @return {string} return.newVal
+ * @return {boolean} return.trimmed
+ */
+ function trimCodePointLength( safeVal, newVal, codePointLimit, filterFn ) {
+ var lengthFn;
+ if ( filterFn ) {
+ lengthFn = function ( val ) {
+ return codePointLength( filterFn( val ) );
+ };
+ } else {
+ lengthFn = codePointLength;
+ }
+
+ return trimLength( safeVal, newVal, codePointLimit, lengthFn );
+ }
+
module.exports = {
byteLength: byteLength,
- trimByteLength: trimByteLength
+ codePointLength: codePointLength,
+ trimByteLength: trimByteLength,
+ trimCodePointLength: trimCodePointLength
};
}() );
dépôts / lhc / web / wiklou.git / blobdiff