diff --git a/tests/merge_unstaged_conflict.R b/tests/merge_unstaged_conflict.R
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+## git2r, R bindings to the libgit2 library.
+## Copyright (C) 2013-2018 The git2r contributors
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License, version 2,
+## as published by the Free Software Foundation.
+##
+## git2r is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License along
+## with this program; if not, write to the Free Software Foundation, Inc.,
+## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+library("git2r")
+
+## For debugging
+sessionInfo()
+
+## Create a directory in tempdir
+path <- tempfile(pattern="git2r-")
+dir.create(path)
+
+## Initialize a repository
+repo <- init(path)
+config(repo, user.name="Alice", user.email="alice@example.org")
+
+## Create a file, add and commit
+writeLines("Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do",
+           con = file.path(path, "test.txt"))
+add(repo, "test.txt")
+commit_1 <- commit(repo, "Commit message 1")
+
+## Create branch, checkout, change file and commit
+b <- checkout(repo, branch = "branch", create = TRUE)
+writeLines(c("Lorem ipsum dolor amet sit, consectetur adipisicing elit, sed do",
+             "eiusmod tempor incididunt ut labore et dolore magna aliqua."),
+           con = file.path(path, "test.txt"))
+add(repo, "test.txt")
+commit(repo, "Commit message branch")
+
+## Checkout master and create a conflicting change
+b <- branches(repo)
+checkout(b[sapply(b, "[", "name") == "master"][[1]], force=TRUE)
+writeLines(c("Lorem ipsum dolor sit amet, adipisicing consectetur elit, sed do",
+             "eiusmod tempor incididunt ut labore et dolore magna aliqua."),
+           con = file.path(path, "test.txt"))
+
+## Attempt to merge with unstaged conflicting change
+status_unstaged <- structure(list(
+    staged = structure(list(), .Names = character(0)),
+    unstaged = structure(list(modified = "test.txt"), .Names = "modified"),
+    untracked = structure(list(), .Names = character(0))),
+    .Names = c("staged", "unstaged", "untracked"),
+    class = "git_status")
+stopifnot(identical(status(repo), status_unstaged))
+m <- merge(repo, "branch")
+stopifnot(identical(m$up_to_date, FALSE))
+stopifnot(identical(m$fast_forward, FALSE))
+stopifnot(identical(m$conflicts, TRUE))
+stopifnot(identical(sha(m), NA_character_))
+stopifnot(identical(format(m), "Merge: Conflicts"))
+
+## Cleanup
+unlink(path, recursive=TRUE)