VIM global multiple line search and replace maintaining indent -

i trying perform multiple line search , replace while retaining indent, leading space, in code working with. below text sample approximates situation. problem i'm having preserving white space. i'm hoping non-plugin, plain jane vim solution via :%s/ ......

vim 7.2 on windows 7 autoindent on expandtab on

starting with:

  apples,   banannas,   cherries,   plums    peas,   green beans,   corn,   squash          apples,         banannas,         cherries,         plums 

i add "pears,", without double quotes , following "cherries," line in list. desired outcome is:

  apples,   banannas,   cherries,   pears,   plums    peas,   green beans,   corn,   squash          apples,         banannas,         cherries,         pears,         plums 

---

trying :%s/cherries,/&\rpears,/g yields ...

      apples,       banannas,       cherries, pears,       plums        peas,       green beans,       corn,       squash              apples,             banannas,             cherries, pears,             plums 

---

trying :%s/cherries,_s.\s*/&pears,\r/g yields ...

      apples,       banannas,       cherries,       pears, plums        peas,       green beans,       corn,       squash              apples,             banannas,             cherries,             pears, plums 

thank you!

you take advantage of :g , auto-indentation normal o:

:g/cherries,/normal opears,