lib/standard: the single parameter of `String::strip_extension` is optional

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/lib/standard/file.nit b/lib/standard/file.nit
index cc6711c..6f2160e 100644 (file)
--- a/lib/standard/file.nit
+++ b/lib/standard/file.nit
@@ -704,21 +704,32 @@ redef class String
        # Copy content of file at `self` to `dest`
        fun file_copy_to(dest: String) do to_path.copy(dest.to_path)
 
-       # Remove the trailing extension `ext`.
+       # Remove the trailing `extension`.
        #
-       # `ext` usually starts with a dot but could be anything.
+       # `extension` usually starts with a dot but could be anything.
        #
-       #     assert "file.txt".strip_extension(".txt")  == "file"
-       #     assert "file.txt".strip_extension("le.txt")  == "fi"
-       #     assert "file.txt".strip_extension("xt")  == "file.t"
+       #     assert "file.txt".strip_extension(".txt")   == "file"
+       #     assert "file.txt".strip_extension("le.txt") == "fi"
+       #     assert "file.txt".strip_extension("xt")     == "file.t"
        #
-       # if `ext` is not present, `self` is returned unmodified.
+       # If `extension == null`, the rightmost extension is stripped, including the last dot.
+       #
+       #     assert "file.txt".strip_extension           == "file"
+       #
+       # If `extension` is not present, `self` is returned unmodified.
        #
        #     assert "file.txt".strip_extension(".tar.gz")  == "file.txt"
-       fun strip_extension(ext: String): String
+       fun strip_extension(extension: nullable String): String
        do
-               if has_suffix(ext) then
-                       return substring(0, length - ext.length)
+               if extension == null then
+                       extension = file_extension
+                       if extension == null then
+                               return self
+                       else extension = ".{extension}"
+               end
+
+               if has_suffix(extension) then
+                       return substring(0, length - extension.length)
                end
                return self
        end