fix: open files under cwd with relative name (#693)

lua/oil/adapters/files.lua

@@ -277,7 +277,7 @@ M.normalize_url = function(url, callback)
           local norm_path = util.addslash(fs.os_to_posix_path(realpath))
           callback(scheme .. norm_path)
         else
-          callback(realpath)
+          callback(vim.fn.fnamemodify(realpath, ":."))
         end
       end)
     )

tests/files_spec.lua

@@ -168,5 +168,6 @@ a.describe("files adapter", function()
     test_util.wait_for_autocmd("BufReadPost")
     assert.equals("ruby", vim.bo.filetype)
     assert.equals(vim.fn.fnamemodify(tmpdir.path, ":p") .. "file.rb", vim.api.nvim_buf_get_name(0))
+    assert.equals(tmpdir.path .. "/file.rb", vim.fn.bufname())
   end)
 end)