X-Git-Url: http://nitlanguage.org

diff --git a/lib/core/text/abstract_text.nit b/lib/core/text/abstract_text.nit
index 90b38b1..e07e0d4 100644
--- a/lib/core/text/abstract_text.nit
+++ b/lib/core/text/abstract_text.nit
@@ -1382,30 +1382,19 @@ abstract class String
 	# Letters that follow a letter are lowercased
 	# Letters that follow a non-letter are upcased.
 	#
+	# If `keep_upper = true`, already uppercase letters are not lowercased.
+	#
 	# SEE : `Char::is_letter` for the definition of letter.
 	#
 	#     assert "jAVASCRIPT".capitalized == "Javascript"
 	#     assert "i am root".capitalized == "I Am Root"
 	#     assert "ab_c -ab0c ab\nc".capitalized == "Ab_C -Ab0C Ab\nC"
-	fun capitalized: SELFTYPE do
+	#     assert "preserve my ACRONYMS".capitalized(keep_upper=true) == "Preserve My ACRONYMS"
+	fun capitalized(keep_upper: nullable Bool): SELFTYPE do
 		if length == 0 then return self
 
 		var buf = new Buffer.with_cap(length)
-
-		var curr = chars[0].to_upper
-		var prev = curr
-		buf[0] = curr
-
-		for i in [1 .. length[ do
-			prev = curr
-			curr = self[i]
-			if prev.is_letter then
-				buf[i] = curr.to_lower
-			else
-				buf[i] = curr.to_upper
-			end
-		end
-
+		buf.capitalize(keep_upper=keep_upper, src=self)
 		return buf.to_s
 	end
 end
@@ -1500,6 +1489,13 @@ abstract class Buffer
 	# Letters that follow a letter are lowercased
 	# Letters that follow a non-letter are upcased.
 	#
+	# If `keep_upper = true`, uppercase letters are not lowercased.
+	#
+	# When `src` is specified, this method reads from `src` instead of `self`
+	# but it still writes the result to the beginning of `self`.
+	# This requires `self` to have the capacity to receive all of the
+	# capitalized content of `src`.
+	#
 	# SEE: `Char::is_letter` for the definition of a letter.
 	#
 	#     var b = new FlatBuffer.from("jAVAsCriPt")
@@ -1511,16 +1507,32 @@ abstract class Buffer
 	#     b = new FlatBuffer.from("ab_c -ab0c ab\nc")
 	#     b.capitalize
 	#     assert b == "Ab_C -Ab0C Ab\nC"
-	fun capitalize do
+	#
+	#     b = new FlatBuffer.from("12345")
+	#     b.capitalize(src="foo")
+	#     assert b == "Foo45"
+	#
+	#     b = new FlatBuffer.from("preserve my ACRONYMS")
+	#     b.capitalize(keep_upper=true)
+	#     assert b == "Preserve My ACRONYMS"
+	fun capitalize(keep_upper: nullable Bool, src: nullable Text) do
+		src = src or else self
+		var length = src.length
 		if length == 0 then return
-		var c = self[0].to_upper
+		keep_upper = keep_upper or else false
+
+		var c = src[0].to_upper
 		self[0] = c
 		var prev = c
 		for i in [1 .. length[ do
 			prev = c
-			c = self[i]
+			c = src[i]
 			if prev.is_letter then
-				self[i] = c.to_lower
+				if keep_upper then
+					self[i] = c
+				else
+					self[i] = c.to_lower
+				end
 			else
 				self[i] = c.to_upper
 			end
@@ -2124,7 +2136,12 @@ end
 # see `alpha_comparator`
 private class AlphaComparator
 	super Comparator
-	redef fun compare(a, b) do return a.to_s <=> b.to_s
+	redef fun compare(a, b) do
+		if a == b then return 0
+		if a == null then return -1
+		if b == null then return 1
+		return a.to_s <=> b.to_s
+	end
 end
 
 # Stateless comparator that naively use `to_s` to compare things.