--- /dev/null
+# string-no-newline
+
+Disallow (unescaped) newlines in strings.
+
+```css
+a {
+ content: "first
+ second"; ↑
+} ↑
+/** ↑
+ * The newline here */
+```
+
+[The spec](https://www.w3.org/TR/CSS2/syndata.html#strings) says this: "A string cannot directly contain a newline. To include a newline in a string, use an escape representing the line feed character in ISO-10646 (U+000A), such as \"\A\" or \"\00000a\"." And also: "It is possible to break strings over several lines, for aesthetic or other reasons, but in such a case the newline itself has to be escaped with a backslash (\)."
+
+## Options
+
+### `true`
+
+The following patterns are considered violations:
+
+```css
+a {
+ content: "first
+ second";
+}
+```
+
+```css
+[title="something
+is probably wrong"] {}
+```
+
+```css
+a {
+ font-family: "Times
+ New
+ Roman";
+}
+```
+
+The following patterns are *not* considered violations:
+
+```css
+a {
+ content: "first\Asecond";
+}
+```
+
+```css
+a {
+ content: "first\\nsecond";
+}
+```
+
+```css
+[title="nothing\
+ is wrong"] {}
+```
+
+```css
+a {
+ font-family: "Times New Roman";
+}
+```