Merge pull request #762 from kachick/implement-string-rjust

Implement String#rjust

spec/tags/core/string/rjust_tags.txt

@@ -1,11 +1,3 @@
-fails:String#rjust with length, padding returns a new string of specified length with self right justified and padded with padstr
-fails:String#rjust with length, padding pads with whitespace if no padstr is given
-fails:String#rjust with length, padding returns self if it's longer than or as long as the specified length
 fails:String#rjust with length, padding taints result when self or padstr is tainted
-fails:String#rjust with length, padding tries to convert length to an integer using to_int
-fails:String#rjust with length, padding raises a TypeError when length can't be converted to an integer
-fails:String#rjust with length, padding tries to convert padstr to a string using to_str
-fails:String#rjust with length, padding raises a TypeError when padstr can't be converted
-fails:String#rjust with length, padding raises an ArgumentError when padstr is empty
 fails:String#rjust with length, padding returns subclass instances when called on subclasses
 fails:String#rjust with length, padding when padding is tainted and self is untainted returns a tainted string if and only if length is longer than self

topaz/objects/stringobject.py

@@ -554,6 +554,22 @@ def method_ljust(self, space, integer, padstr=" "):
             chars += padstr[:pad_len % len(padstr) + 1]
             return space.newstr_fromchars(chars)
 
+    @classdef.method("rjust", integer="int", padstr="str")
+    def method_rjust(self, space, integer, padstr=" "):
+        if not padstr:
+            raise space.error(space.w_ArgumentError, "zero width padding")
+        elif integer <= self.length():
+            return self.copy(space)
+        else:
+            pad_len = integer - self.length() - 1
+            assert pad_len >= 0
+            chars = []
+            for i in xrange(pad_len / len(padstr)):
+                chars += padstr
+            chars += padstr[:pad_len % len(padstr) + 1]
+            chars += space.str_w(self)
+            return space.newstr_fromchars(chars)
+
     def search_context(self, space, ctx):
         try:
             return rsre_core.search_context(ctx)