Title says it all. Here is some example code.

String test = '\n\n\n\n'; // All New Line characters

System.debug( String.isBlank(test) ); // Returns true
System.debug( String.isEmpty(test) ); // Returns false
System.debug( test ); // Yields several empty lines in the debug output.

test = test.stripHtmlTags();

System.debug( String.isBlank(test) ); // Returns true
System.debug( String.isEmpty(test) ); // Returns true
System.debug( test ); // Yields no empty lines in the debug output

So I have a String which may or may not have HTML tags. I want to remove the HTML tags and translate <br> to new lines \n, which stripHtmlTags does fine.

My problem is that I may not always have HTML in my string, and when I do not have HTML I still want to keep my formatting.

stripHtmlTags also removed carriage return \r and tab space \t and possibly others I didn't check.

UPDATE

This is the official response from Salesforce on the issue. stripHtmlTags() is WAD and they are going to update the documentation to reflect the fact that it removes white-space characters as well as HTML tags.

As per update from the team, we have revisited the implementation of the method, we have created a Doc Bug to make note of this in our documentation. The whitespace characters in the string get stripped.

So, a Doc Bug has been logged for this to be included that whitespace kind of characters is not preserved when using this method.