Merge pull request #3498 from ethomson/windows_symlinks

Diff: Honor `core.symlinks=false` and fake symlinks

3 files changed, 115 insertions, 0 deletions

diff --git a/src/diff_file.c b/src/diff_file.c
index c60362865..ecc34cf55 100644
--- a/src/diff_file.c
+++ b/src/diff_file.c
@@ -259,10 +259,35 @@ static int diff_file_content_load_blob(
 	return error;
 }
 
+static int diff_file_content_load_workdir_symlink_fake(
+	git_diff_file_content *fc, git_buf *path)
+{
+	git_buf target = GIT_BUF_INIT;
+	int error;
+
+	if ((error = git_futils_readbuffer(&target, path->ptr)) < 0)
+		return error;
+
+	fc->map.len = git_buf_len(&target);
+	fc->map.data = git_buf_detach(&target);
+	fc->flags |= GIT_DIFF_FLAG__FREE_DATA;
+
+	git_buf_free(&target);
+	return error;
+}
+
 static int diff_file_content_load_workdir_symlink(
 	git_diff_file_content *fc, git_buf *path)
 {
 	ssize_t alloc_len, read_len;
+	int symlink_supported, error;
+
+	if ((error = git_repository__cvar(
+		&symlink_supported, fc->repo, GIT_CVAR_SYMLINKS)) < 0)
+		return -1;
+
+	if (!symlink_supported)
+		return diff_file_content_load_workdir_symlink_fake(fc, path);
 
 	/* link path on disk could be UTF-16, so prepare a buffer that is
 	 * big enough to handle some UTF-8 data expansion
diff --git a/tests/diff/workdir.c b/tests/diff/workdir.c
index dac32453b..4c782339d 100644
--- a/tests/diff/workdir.c
+++ b/tests/diff/workdir.c
@@ -2097,3 +2097,64 @@ void test_diff_workdir__to_index_pathlist(void)
 	git_vector_free(&pathlist);
 }
 
+void test_diff_workdir__symlink_changed_on_non_symlink_platform(void)
+{
+	git_tree *tree;
+	git_diff *diff;
+	diff_expects exp = {0};
+	const git_diff_delta *delta;
+	const char *commit = "7fccd7";
+	git_diff_options opts = GIT_DIFF_OPTIONS_INIT;
+	git_vector pathlist = GIT_VECTOR_INIT;
+	int symlinks;
+
+	g_repo = cl_git_sandbox_init("unsymlinked.git");
+
+	cl_git_pass(git_repository__cvar(&symlinks, g_repo, GIT_CVAR_SYMLINKS));
+
+	if (symlinks)
+		cl_skip();
+
+	cl_git_pass(git_vector_insert(&pathlist, "include/Nu/Nu.h"));
+
+	opts.pathspec.strings = (char **)pathlist.contents;
+	opts.pathspec.count = pathlist.length;
+
+	cl_must_pass(p_mkdir("symlink", 0777));
+	cl_git_pass(git_repository_set_workdir(g_repo, "symlink", false));
+
+	cl_assert((tree = resolve_commit_oid_to_tree(g_repo, commit)) != NULL);
+
+	/* first, do the diff with the original contents */
+
+	cl_git_pass(git_futils_mkpath2file("symlink/include/Nu/Nu.h", 0755));
+	cl_git_mkfile("symlink/include/Nu/Nu.h", "../../objc/Nu.h");
+
+	cl_git_pass(git_diff_tree_to_workdir(&diff, g_repo, tree, &opts));
+	cl_assert_equal_i(0, git_diff_num_deltas(diff));
+	git_diff_free(diff);
+
+	/* now update the contents and expect a difference, but that the file
+	 * mode has persisted as a symbolic link.
+	 */
+
+	cl_git_rewritefile("symlink/include/Nu/Nu.h", "awesome content\n");
+
+	cl_git_pass(git_diff_tree_to_workdir(&diff, g_repo, tree, &opts));
+
+	cl_git_pass(git_diff_foreach(
+		diff, diff_file_cb, diff_binary_cb, diff_hunk_cb, diff_line_cb, &exp));
+	cl_assert_equal_i(1, exp.files);
+
+	cl_assert_equal_i(1, git_diff_num_deltas(diff));
+	delta = git_diff_get_delta(diff, 0);
+	cl_assert_equal_i(GIT_FILEMODE_LINK, delta->old_file.mode);
+	cl_assert_equal_i(GIT_FILEMODE_LINK, delta->new_file.mode);
+
+	git_diff_free(diff);
+
+	cl_git_pass(git_futils_rmdir_r("symlink", NULL, GIT_RMDIR_REMOVE_FILES));
+
+	git_tree_free(tree);
+	git_vector_free(&pathlist);
+}
diff --git a/tests/index/bypath.c b/tests/index/bypath.c
index 0c10cfe4c..88a76178a 100644
--- a/tests/index/bypath.c
+++ b/tests/index/bypath.c
@@ -328,3 +328,32 @@ void test_index_bypath__add_honors_conflict_case(void)
 	cl_assert((entry = git_index_get_bypath(g_idx, "README.txt", 0)) != NULL);
 	cl_assert_equal_i(GIT_FILEMODE_BLOB_EXECUTABLE, entry->mode);
 }
+
+void test_index_bypath__add_honors_symlink(void)
+{
+	const git_index_entry *entry;
+	git_index_entry new_entry;
+	int symlinks;
+
+	cl_git_pass(git_repository__cvar(&symlinks, g_repo, GIT_CVAR_SYMLINKS));
+
+	if (symlinks)
+		cl_skip();
+
+	cl_assert((entry = git_index_get_bypath(g_idx, "README.txt", 0)) != NULL);
+
+	memcpy(&new_entry, entry, sizeof(git_index_entry));
+	new_entry.path = "README.txt";
+	new_entry.mode = GIT_FILEMODE_LINK;
+
+	cl_git_pass(git_index_add(g_idx, &new_entry));
+	cl_git_pass(git_index_write(g_idx));
+
+	cl_git_rewritefile("submod2/README.txt", "Modified but still a (fake) symlink");
+
+	cl_git_pass(git_index_add_bypath(g_idx, "README.txt"));
+	cl_git_pass(git_index_write(g_idx));
+
+	cl_assert((entry = git_index_get_bypath(g_idx, "README.txt", 0)) != NULL);
+	cl_assert_equal_i(GIT_FILEMODE_LINK, entry->mode);
+}