fix(base): add tests for self:remove_suffix

Author: pysan3

lua/pathlib/base.lua

@@ -356,8 +356,9 @@ end
 ---@param suffix string # Remove this suffix from path.
 function Path:remove_suffix(suffix)
   local basename = self:basename()
-  if basename:sub(-suffix:len()) == suffix then
-    basename = basename:sub(1, -suffix:len() - 1)
+  local suffix_length = suffix:len()
+  if suffix_length > 0 and basename:sub(-suffix_length) == suffix then
+    basename = basename:sub(1, -suffix_length - 1)
   end
   return self:with_basename(basename)
 end

spec/stem_suffix_spec.lua

@@ -159,10 +159,36 @@ describe("Stem / Suffix Test", function()
     }
     for _, test in ipairs(test_table) do
       local a, suffix, b = unpack(test)
-      it(string.format("%s - '%s' -> %s", a, suffix, b), function()
+      it(string.format("add: %s - '%s' -> %s", a, suffix, b), function()
         assert.are_equal(Posix(b), Posix(a):add_suffix(suffix))
         assert.are_equal(Windows(b), Windows(a):add_suffix(suffix))
       end)
     end
   end)
+
+  describe("add_suffix", function()
+    local test_table = { -- from, suffix, to
+      { "folder/foo.txt", ".png", "folder/foo.txt.png" },
+      { "folder/foo.txt", ".txt", "folder/foo.txt.txt" },
+      { "foo.txt", ".bak", "foo.txt.bak" },
+      { "foo.tar", ".zip", "foo.tar.zip" },
+      { "foo.tar.gz", ".zip", "foo.tar.gz.zip" },
+      { "foo.png", ".tar.gz", "foo.png.tar.gz" },
+      { ".bashrc", ".zshrc", ".bashrc.zshrc" },
+      { "", ".zshrc", ".zshrc" },
+      { "foo", ".zip", "foo.zip" },
+      { "foo.txt", "", "foo.txt" },
+      { "my.awesome.file.png", "", "my.awesome.file.png" },
+      { "my.awesome.file.", "", "my.awesome.file." },
+      { "my.awesome.file.png", ".txt", "my.awesome.file.png.txt" },
+      { "my.awesome.file..", ".png", "my.awesome.file...png" },
+    }
+    for _, test in ipairs(test_table) do
+      local a, suffix, b = unpack(test)
+      it(string.format("remove: %s - '%s' -> %s", b, suffix, a), function()
+        assert.are_equal(Posix(a), Posix(b):remove_suffix(suffix))
+        assert.are_equal(Windows(a), Windows(b):remove_suffix(suffix))
+      end)
+    end
+  end)
 end)