file: Fix `join_path` to handle paths ending with a slash.

Signed-off-by: Jean-Christophe Beaupré <jcbrinfo@users.noreply.github.com>

diff --git a/lib/standard/file.nit b/lib/standard/file.nit
index b8f5bab..30e48e3 100644 (file)
--- a/lib/standard/file.nit
+++ b/lib/standard/file.nit
@@ -328,24 +328,30 @@ redef class String
 
        # Correctly join two path using the directory separator.
        #
-       # Using a standard "{self}/{path}" does not work when `self` is the empty string.
-       # This method ensure that the join is valid.
+       # Using a standard "{self}/{path}" does not work in the following cases:
        #
-       #     assert "hello".join_path("world")      ==  "hello/world"
-       #     assert "hel/lo".join_path("wor/ld")      ==  "hel/lo/wor/ld"
-       #     assert "".join_path("world")      ==  "world"
-       #     assert "/hello".join_path("/world")      ==  "/world"
+       # * `self` is empty.
+       # * `path` ends with `'/'`.
+       # * `path` starts with `'/'`.
        #
-       # Note: you may want to use `simplify_path` on the result
+       # This method ensures that the join is valid.
        #
-       # Note: I you want to join a great number of path, you can write
+       #     assert "hello".join_path("world")   == "hello/world"
+       #     assert "hel/lo".join_path("wor/ld") == "hel/lo/wor/ld"
+       #     assert "".join_path("world")        == "world"
+       #     assert "hello".join_path("/world")  == "/world"
+       #     assert "hello/".join_path("world")  == "hello/world"
+       #     assert "hello/".join_path("/world") == "/world"
        #
-       #     [p1, p2, p3, p4].join("/")
+       # Note: You may want to use `simplify_path` on the result.
+       #
+       # Note: This method works only with POSIX paths.
        fun join_path(path: String): String
        do
                if path.is_empty then return self
                if self.is_empty then return path
                if path.chars[0] == '/' then return path
+               if self.last == '/' then return "{self}{path}"
                return "{self}/{path}"
        end