Merge pull request #1563 from aihowes/master

Add truncateAtSpace

snippets/truncateStringAtWhitespace.md

@@ -0,0 +1,26 @@
+---
+title: truncateStringAtWhitespace
+tags: string,intermediate
+---
+
+Truncates a string up to specified length, respecting whitespace when possible.
+
+- Determine if the string's `length` is greater or equal to `lim`. If not, return it as-is.
+- Use `String.prototype.slice()` and `String.prototype.lastIndexOf()` to find the index of the last space below the desired `lim`.
+- Use `String.prototype.slice()` to appropriately truncate `str` based on `lastSpace`, respecting whitespace if possible and appending `ending` at the end.
+- Omit the third argument, `ending`, to use the default ending of `'...'`.
+
+```js
+const truncateStringAtWhitespace = (str, lim, ending = '...') => {
+  if (str.length <= lim) return str;
+  const lastSpace = str.slice(0, lim - ending.length + 1).lastIndexOf(' ');
+  return str.slice(0, lastSpace > 0 ? lastSpace : lim - ending.length) + ending;
+};
+```
+
+```js
+truncateStringAtWhitespace('short', 10); // 'short'
+truncateStringAtWhitespace('not so short', 10); // 'not so...'
+truncateStringAtWhitespace('trying a thing', 10); // 'trying...'
+truncateStringAtWhitespace('javascripting', 10); // 'javascr...'
+```