checkout tests: test symlinks based on support, not platform

When testing whether symlinks are correctly checked out, examine the
`core.symlinks` configuration option to determine if symlinks are
supported in a repository, don't simply assume that Windows means that
symbolic links are not supported.

Further, when testing the expected default behavior of `core.symlinks`,
test the filesystem's support to determine if symlinks are supported.

Finally, ensure that `core.symlinks=true` fails on a system where
symlinks are actually not supported.  This aligns with the behavior of
Git for Windows.

3 files changed, 121 insertions, 72 deletions

diff --git a/tests/checkout/conflict.c b/tests/checkout/conflict.c
index 90603d4b7..6670b2ec7 100644
--- a/tests/checkout/conflict.c
+++ b/tests/checkout/conflict.c
@@ -2,6 +2,7 @@
 #include "git2/repository.h"
 #include "git2/sys/index.h"
 #include "fileops.h"
+#include "repository.h"
 
 static git_repository *g_repo;
 static git_index *g_index;
@@ -184,28 +185,35 @@ static void ensure_workdir(const char *path, int mode, const char *oid_str)
 	ensure_workdir_oid(path, oid_str);
 }
 
-static void ensure_workdir_link(const char *path, const char *target)
+static void ensure_workdir_link(
+	git_repository *repo,
+	const char *path,
+	const char *target)
 {
-#ifdef GIT_WIN32
-	ensure_workdir_contents(path, target);
-#else
-	git_buf fullpath = GIT_BUF_INIT;
-	char actual[1024];
-	struct stat st;
-	int len;
+	int symlinks;
 
-	cl_git_pass(
-		git_buf_joinpath(&fullpath, git_repository_workdir(g_repo), path));
+	cl_git_pass(git_repository__cvar(&symlinks, repo, GIT_CVAR_SYMLINKS));
 
-	cl_git_pass(p_lstat(git_buf_cstr(&fullpath), &st));
-	cl_assert(S_ISLNK(st.st_mode));
+	if (!symlinks) {
+		ensure_workdir_contents(path, target);
+	} else {
+		git_buf fullpath = GIT_BUF_INIT;
+		char actual[1024];
+		struct stat st;
+		int len;
 
-	cl_assert((len = p_readlink(git_buf_cstr(&fullpath), actual, 1024)) > 0);
-	actual[len] = '\0';
-	cl_assert(strcmp(actual, target) == 0);
+		cl_git_pass(
+			git_buf_joinpath(&fullpath, git_repository_workdir(g_repo), path));
 
-	git_buf_dispose(&fullpath);
-#endif
+		cl_git_pass(p_lstat(git_buf_cstr(&fullpath), &st));
+		cl_assert(S_ISLNK(st.st_mode));
+
+		cl_assert((len = p_readlink(git_buf_cstr(&fullpath), actual, 1024)) > 0);
+		actual[len] = '\0';
+		cl_assert(strcmp(actual, target) == 0);
+
+		git_buf_dispose(&fullpath);
+	}
 }
 
 void test_checkout_conflict__ignored(void)
@@ -415,8 +423,8 @@ void test_checkout_conflict__links(void)
 	cl_git_pass(git_checkout_index(g_repo, g_index, &opts));
 
 	/* Conflicts with links always keep the ours side (even with -Xtheirs) */
-	ensure_workdir_link("link-1", LINK_OURS_TARGET);
-	ensure_workdir_link("link-2", LINK_OURS_TARGET);
+	ensure_workdir_link(g_repo, "link-1", LINK_OURS_TARGET);
+	ensure_workdir_link(g_repo, "link-2", LINK_OURS_TARGET);
 }
 
 void test_checkout_conflict__add_add(void)
@@ -684,7 +692,7 @@ void test_checkout_conflict__renames(void)
 void test_checkout_conflict__rename_keep_ours(void)
 {
 	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
-	
+
 	struct checkout_index_entry checkout_index_entries[] = {
 		{ 0100644, "68c6c84b091926c7d90aa6a79b2bc3bb6adccd8e", 0, "0a-no-change.txt" },
 		{ 0100644, "f0ce2b8e4986084d9b308fb72709e414c23eb5e6", 0, "0b-duplicated-in-ours.txt" },
@@ -728,122 +736,122 @@ void test_checkout_conflict__rename_keep_ours(void)
 		{ 0100644, "b42712cfe99a1a500b2a51fe984e0b8a7702ba11", 2, "7-both-renamed.txt" },
 		{ 0100644, "b69fe837e4cecfd4c9a40cdca7c138468687df07", 3, "7-both-renamed.txt" }
 	};
-	
+
 	struct checkout_name_entry checkout_name_entries[] = {
 		{
 			"3a-renamed-in-ours-deleted-in-theirs.txt",
 			"3a-newname-in-ours-deleted-in-theirs.txt",
 			""
 		},
-		
+
 		{
 			"3b-renamed-in-theirs-deleted-in-ours.txt",
 			"",
 			"3b-newname-in-theirs-deleted-in-ours.txt"
 		},
-		
+
 		{
 			"4a-renamed-in-ours-added-in-theirs.txt",
 			"4a-newname-in-ours-added-in-theirs.txt",
 			""
 		},
-		
+
 		{
 			"4b-renamed-in-theirs-added-in-ours.txt",
 			"",
 			"4b-newname-in-theirs-added-in-ours.txt"
 		},
-		
+
 		{
 			"5a-renamed-in-ours-added-in-theirs.txt",
 			"5a-newname-in-ours-added-in-theirs.txt",
 			"5a-renamed-in-ours-added-in-theirs.txt"
 		},
-		
+
 		{
 			"5b-renamed-in-theirs-added-in-ours.txt",
 			"5b-renamed-in-theirs-added-in-ours.txt",
 			"5b-newname-in-theirs-added-in-ours.txt"
 		},
-		
+
 		{
 			"6-both-renamed-1-to-2.txt",
 			"6-both-renamed-1-to-2-ours.txt",
 			"6-both-renamed-1-to-2-theirs.txt"
 		},
-		
+
 		{
 			"7-both-renamed-side-1.txt",
 			"7-both-renamed.txt",
 			"7-both-renamed-side-1.txt"
 		},
-		
+
 		{
 			"7-both-renamed-side-2.txt",
 			"7-both-renamed-side-2.txt",
 			"7-both-renamed.txt"
 		}
 	};
-	
+
 	opts.checkout_strategy |= GIT_CHECKOUT_SAFE | GIT_CHECKOUT_USE_OURS;
-	
+
 	create_index(checkout_index_entries, 41);
 	create_index_names(checkout_name_entries, 9);
 	cl_git_pass(git_index_write(g_index));
-	
+
 	cl_git_pass(git_checkout_index(g_repo, g_index, &opts));
-		
+
 	ensure_workdir("0a-no-change.txt",
 				   0100644, "68c6c84b091926c7d90aa6a79b2bc3bb6adccd8e");
-	
+
 	ensure_workdir("0b-duplicated-in-ours.txt",
 				   0100644, "f0ce2b8e4986084d9b308fb72709e414c23eb5e6");
-	
+
 	ensure_workdir("0b-rewritten-in-ours.txt",
 				   0100644, "e376fbdd06ebf021c92724da9f26f44212734e3e");
-	
+
 	ensure_workdir("0c-duplicated-in-theirs.txt",
 				   0100644, "2f56120107d680129a5d9791b521cb1e73a2ed31");
-	
+
 	ensure_workdir("0c-rewritten-in-theirs.txt",
 				   0100644, "efc9121fdedaf08ba180b53ebfbcf71bd488ed09");
-	
+
 	ensure_workdir("1a-newname-in-ours-edited-in-theirs.txt",
 				   0100644, "0d872f8e871a30208305978ecbf9e66d864f1638");
-	
+
 	ensure_workdir("1a-newname-in-ours.txt",
 				   0100644, "d0d4594e16f2e19107e3fa7ea63e7aaaff305ffb");
-	
+
 	ensure_workdir("1b-newname-in-theirs-edited-in-ours.txt",
 				   0100644, "ed9523e62e453e50dd9be1606af19399b96e397a");
-	
+
 	ensure_workdir("1b-newname-in-theirs.txt",
 				   0100644, "2b5f1f181ee3b58ea751f5dd5d8f9b445520a136");
-	
+
 	ensure_workdir("2-newname-in-both.txt",
 				   0100644, "178940b450f238a56c0d75b7955cb57b38191982");
 
 	ensure_workdir("3a-newname-in-ours-deleted-in-theirs.txt",
 				   0100644, "18cb316b1cefa0f8a6946f0e201a8e1a6f845ab9");
-	
+
 	ensure_workdir("3b-newname-in-theirs-deleted-in-ours.txt",
 				   0100644, "36219b49367146cb2e6a1555b5a9ebd4d0328495");
-	
+
 	ensure_workdir("4a-newname-in-ours-added-in-theirs.txt",
 				   0100644, "227792b52aaa0b238bea00ec7e509b02623f168c");
-	
+
 	ensure_workdir("4b-newname-in-theirs-added-in-ours.txt",
 				   0100644, "de872ee3618b894992e9d1e18ba2ebe256a112f9");
-	
+
 	ensure_workdir("5a-newname-in-ours-added-in-theirs.txt",
 				   0100644, "d3719a5ae8e4d92276b5313ce976f6ee5af2b436");
-		
+
 	ensure_workdir("5b-newname-in-theirs-added-in-ours.txt",
 				   0100644, "385c8a0f26ddf79e9041e15e17dc352ed2c4cced");
 
 	ensure_workdir("6-both-renamed-1-to-2-ours.txt",
 				   0100644, "d8fa77b6833082c1ea36b7828a582d4c43882450");
-	
+
 	ensure_workdir("7-both-renamed.txt",
 				   0100644, "b42712cfe99a1a500b2a51fe984e0b8a7702ba11");
 }
diff --git a/tests/checkout/icase.c b/tests/checkout/icase.c
index d804d086e..4aa78a869 100644
--- a/tests/checkout/icase.c
+++ b/tests/checkout/icase.c
@@ -3,6 +3,7 @@
 #include "git2/checkout.h"
 #include "refs.h"
 #include "path.h"
+#include "repository.h"
 
 #ifdef GIT_WIN32
 # include <windows.h>
@@ -91,6 +92,18 @@ static void assert_name_is(const char *expected)
 	free(actual);
 }
 
+static int symlink_or_fake(git_repository *repo, const char *a, const char *b)
+{
+	int symlinks;
+
+	cl_git_pass(git_repository__cvar(&symlinks, repo, GIT_CVAR_SYMLINKS));
+
+	if (symlinks)
+		return p_symlink(a, b);
+	else
+		return git_futils_fake_symlink(a, b);
+}
+
 void test_checkout_icase__refuses_to_overwrite_files_for_files(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE|GIT_CHECKOUT_RECREATE_MISSING;
@@ -117,7 +130,7 @@ void test_checkout_icase__refuses_to_overwrite_links_for_files(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE|GIT_CHECKOUT_RECREATE_MISSING;
 
-	cl_must_pass(p_symlink("../tmp", "testrepo/BRANCH_FILE.txt"));
+	cl_must_pass(symlink_or_fake(repo, "../tmp", "testrepo/BRANCH_FILE.txt"));
 
 	cl_git_fail(git_checkout_tree(repo, obj, &checkout_opts));
 
@@ -129,7 +142,7 @@ void test_checkout_icase__overwrites_links_for_files_when_forced(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_FORCE;
 
-	cl_must_pass(p_symlink("../tmp", "testrepo/NEW.txt"));
+	cl_must_pass(symlink_or_fake(repo, "../tmp", "testrepo/NEW.txt"));
 
 	cl_git_pass(git_checkout_tree(repo, obj, &checkout_opts));
 
@@ -205,7 +218,7 @@ void test_checkout_icase__refuses_to_overwrite_links_for_folders(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE|GIT_CHECKOUT_RECREATE_MISSING;
 
-	cl_must_pass(p_symlink("..", "testrepo/A"));
+	cl_must_pass(symlink_or_fake(repo, "..", "testrepo/A"));
 
 	cl_git_fail(git_checkout_tree(repo, obj, &checkout_opts));
 
@@ -217,7 +230,7 @@ void test_checkout_icase__overwrites_links_for_folders_when_forced(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_FORCE;
 
-	cl_must_pass(p_symlink("..", "testrepo/A"));
+	cl_must_pass(symlink_or_fake(repo, "..", "testrepo/A"));
 
 	cl_git_pass(git_checkout_tree(repo, obj, &checkout_opts));
 
diff --git a/tests/checkout/index.c b/tests/checkout/index.c
index 69252e3d9..452362662 100644
--- a/tests/checkout/index.c
+++ b/tests/checkout/index.c
@@ -136,6 +136,25 @@ void test_checkout_index__honor_coreautocrlf_setting_set_to_true(void)
 #endif
 }
 
+static bool supports_symlinks(const char *dir)
+{
+	git_buf path = GIT_BUF_INIT;
+	struct stat st;
+	bool supports_symlinks = 1;
+
+	cl_git_pass(git_buf_joinpath(&path, dir, "test"));
+
+	/* see if symlinks are supported in the "symlink" directory */
+	if (p_symlink("target", path.ptr) < 0 ||
+	    p_lstat(path.ptr, &st) < 0 ||
+	    ! (S_ISLNK(st.st_mode)))
+		supports_symlinks = 0;
+
+	git_buf_dispose(&path);
+
+	return supports_symlinks;
+}
+
 void test_checkout_index__honor_coresymlinks_default(void)
 {
 	git_repository *repo;
@@ -162,10 +181,9 @@ void test_checkout_index__honor_coresymlinks_default(void)
 	git_object_free(target);
 	git_repository_free(repo);
 
-#ifdef GIT_WIN32
-	check_file_contents("./symlink/link_to_new.txt", "new.txt");
-#else
-	{
+	if (!supports_symlinks("symlink")) {
+		check_file_contents("./symlink/link_to_new.txt", "new.txt");
+	} else {
 		char link_data[1024];
 		size_t link_size = 1024;
 
@@ -175,14 +193,33 @@ void test_checkout_index__honor_coresymlinks_default(void)
 		cl_assert_equal_s(link_data, "new.txt");
 		check_file_contents("./symlink/link_to_new.txt", "my new file\n");
 	}
-#endif
 
 	cl_fixture_cleanup("symlink");
 }
 
+void test_checkout_index__coresymlinks_set_to_true_fails_when_unsupported(void)
+{
+	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
+
+	if (supports_symlinks("testrepo")) {
+		cl_skip();
+	}
+
+	cl_repo_set_bool(g_repo, "core.symlinks", true);
+
+	opts.checkout_strategy = GIT_CHECKOUT_SAFE | GIT_CHECKOUT_RECREATE_MISSING;
+	cl_git_fail(git_checkout_index(g_repo, NULL, &opts));
+}
+
 void test_checkout_index__honor_coresymlinks_setting_set_to_true(void)
 {
 	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
+	char link_data[GIT_PATH_MAX];
+	size_t link_size = GIT_PATH_MAX;
+
+	if (!supports_symlinks("testrepo")) {
+		cl_skip();
+	}
 
 	cl_repo_set_bool(g_repo, "core.symlinks", true);
 
@@ -190,20 +227,11 @@ void test_checkout_index__honor_coresymlinks_setting_set_to_true(void)
 
 	cl_git_pass(git_checkout_index(g_repo, NULL, &opts));
 
-#ifdef GIT_WIN32
-	check_file_contents("./testrepo/link_to_new.txt", "new.txt");
-#else
-	{
-		char link_data[1024];
-		size_t link_size = 1024;
-
-		link_size = p_readlink("./testrepo/link_to_new.txt", link_data, link_size);
-		link_data[link_size] = '\0';
-		cl_assert_equal_i(link_size, strlen("new.txt"));
-		cl_assert_equal_s(link_data, "new.txt");
-		check_file_contents("./testrepo/link_to_new.txt", "my new file\n");
-	}
-#endif
+	link_size = p_readlink("./testrepo/link_to_new.txt", link_data, link_size);
+	link_data[link_size] = '\0';
+	cl_assert_equal_i(link_size, strlen("new.txt"));
+	cl_assert_equal_s(link_data, "new.txt");
+	check_file_contents("./testrepo/link_to_new.txt", "my new file\n");
 }
 
 void test_checkout_index__honor_coresymlinks_setting_set_to_false(void)
@@ -474,7 +502,7 @@ void test_checkout_index__can_overcome_name_clashes(void)
 	cl_assert(git_path_isfile("./testrepo/path0/file0"));
 
 	opts.checkout_strategy =
-		GIT_CHECKOUT_SAFE | 
+		GIT_CHECKOUT_SAFE |
 		GIT_CHECKOUT_RECREATE_MISSING |
 		GIT_CHECKOUT_ALLOW_CONFLICTS;
 	cl_git_pass(git_checkout_index(g_repo, index, &opts));