Merge pull request #641 from topazproject/tim/String#strip

Add String#strip

lib-topaz/string.rb

@@ -35,7 +35,7 @@ def casecmp(other)
     unless other.respond_to?(:to_str)
       raise TypeError.new("can't convert #{other.class} into String")
     end
-    
+
     other = other.to_str
     diff = self.length - other.length
     short = diff < 0
@@ -156,4 +156,10 @@ def upto(max, exclusive = false, &block)
 
     return self
   end
+
+  def strip
+    duplicate = self.dup
+    duplicate.strip!
+    duplicate
+  end
 end

topaz/objects/stringobject.py

@@ -292,6 +292,33 @@ def insert(self, storage, idx, other):
             storage.insert(idx, char)
             idx += 1
 
+    def strip(self, storage):
+        storage = self.unerase(storage)
+        if not storage:
+            return False
+
+        shift = 0
+        while shift < len(storage) and storage[shift].isspace():
+            shift += 1
+        if shift == len(storage):
+            del storage[:]
+            return True
+
+        pop = len(storage)
+        while pop > 0 and storage[pop - 1].isspace() or storage[pop - 1] == '\0':
+            pop -= 1
+
+        if pop < len(storage) or shift > 0:
+            end = pop
+            new_len = end - shift
+            assert end >= 0
+            assert new_len >= 0
+            storage[0:new_len] = storage[shift:end]
+            del storage[new_len:]
+            return True
+        else:
+            return False
+
 
 class W_StringObject(W_Object):
     classdef = ClassDef("String", W_Object.classdef, filepath=__file__)
@@ -1026,3 +1053,13 @@ def method_insert(self, space, index, other):
         self.strategy.to_mutable(space, self)
         self.strategy.insert(self.str_storage, index, other)
         return self
+
+    @classdef.method("strip!")
+    @check_frozen()
+    def method_strip_i(self, space):
+        self.strategy.to_mutable(space, self)
+        changed = self.strategy.strip(self.str_storage)
+        if changed:
+            return self
+        else:
+            return space.w_nil