Why does vim surround add spaces in this example?

Question

Old text             Command         New text
Hello *world         ysiw(           Hello ( world )
Hello *world         ysiwb           Hello (world)
Hello *world          ysiw)           Hello (world)

Why does vim-surround add spaces to the first example, and is there a way to disable this?

Where the asterisk denotes cursor position

Answer 1

The plugin vim surround allows you to choose whether you want spaces and parenthesis or just parenthesis. You can disable it by using other mappings; actually you pasted them in your question, as the second and third examples.

This is actually a pattern in the mappings of this plugin: if you use the opening character - e.g.: (, { and [ - them it will include spaces. If you use the closing character - e.g.: ), } and ] - them it won't include spaces. The aliases for these blocks (b, B and r) also doesn't includes the spaces, probably because most of time the people (like you) doesn't want the spaces.