Unexpected indent in R language

[pwwang]

Original code

alist = list(a=1,b=2)
alist[["a"]] = 3
alist$b = 4

After align:

      alist   = list(a=1,b=2)
alist[["a"]]  = 3
      alist$b = 4

Expected:

alist         = list(a=1,b=2)
alist[["a"]]  = 3
alist$b       = 4

All options are left as default.

[zeroone2005]

php have the same problem， i set indentBase dontchange, not run