Introduce `git_filter_list_contains`

`git_filter_list_contains` can be used to query a filter list to
determine if a given filter will be run.

1 files changed, 91 insertions, 0 deletions

diff --git a/tests/filter/query.c b/tests/filter/query.c
new file mode 100644
index 000000000..6889d715b
--- /dev/null
+++ b/tests/filter/query.c
@@ -0,0 +1,91 @@
+#include "clar_libgit2.h"
+#include "git2/sys/filter.h"
+#include "crlf.h"
+#include "buffer.h"
+
+static git_repository *g_repo = NULL;
+
+void test_filter_query__initialize(void)
+{
+	g_repo = cl_git_sandbox_init("crlf");
+
+	cl_git_mkfile("crlf/.gitattributes",
+		"*.txt text\n"
+		"*.bin binary\n"
+		"*.crlf text eol=crlf\n"
+		"*.lf text eol=lf\n"
+		"*.binident binary ident\n"
+		"*.ident text ident\n"
+		"*.identcrlf ident text eol=crlf\n"
+		"*.identlf ident text eol=lf\n"
+		"*.custom custom ident text\n");
+}
+
+void test_filter_query__cleanup(void)
+{
+	cl_git_sandbox_cleanup();
+}
+
+static int filter_for(const char *filename, const char *filter)
+{
+	git_filter_list *fl;
+	int filtered;
+
+	cl_git_pass(git_filter_list_load(
+		&fl, g_repo, NULL, filename, GIT_FILTER_TO_WORKTREE, 0));
+	filtered = git_filter_list_contains(fl, filter);
+	git_filter_list_free(fl);
+
+	return filtered;
+}
+
+void test_filter_query__filters(void)
+{
+	cl_assert_equal_i(1, filter_for("text.txt", "crlf"));
+	cl_assert_equal_i(0, filter_for("binary.bin", "crlf"));
+
+	cl_assert_equal_i(1, filter_for("foo.lf", "crlf"));
+	cl_assert_equal_i(0, filter_for("foo.lf", "ident"));
+
+	cl_assert_equal_i(1, filter_for("id.ident", "crlf"));
+	cl_assert_equal_i(1, filter_for("id.ident", "ident"));
+
+	cl_assert_equal_i(0, filter_for("id.binident", "crlf"));
+	cl_assert_equal_i(1, filter_for("id.binident", "ident"));
+}
+
+void test_filter_query__autocrlf_true_implies_crlf(void)
+{
+	cl_repo_set_bool(g_repo, "core.autocrlf", true);
+	cl_assert_equal_i(1, filter_for("not_in_gitattributes", "crlf"));
+	cl_assert_equal_i(1, filter_for("foo.txt", "crlf"));
+	cl_assert_equal_i(0, filter_for("foo.bin", "crlf"));
+	cl_assert_equal_i(1, filter_for("foo.lf", "crlf"));
+
+	cl_repo_set_bool(g_repo, "core.autocrlf", false);
+	cl_assert_equal_i(0, filter_for("not_in_gitattributes", "crlf"));
+	cl_assert_equal_i(1, filter_for("foo.txt", "crlf"));
+	cl_assert_equal_i(0, filter_for("foo.bin", "crlf"));
+	cl_assert_equal_i(1, filter_for("foo.lf", "crlf"));
+}
+
+void test_filter_query__unknown(void)
+{
+	cl_assert_equal_i(1, filter_for("foo.custom", "crlf"));
+	cl_assert_equal_i(1, filter_for("foo.custom", "ident"));
+	cl_assert_equal_i(0, filter_for("foo.custom", "custom"));
+}
+
+void test_filter_query__custom(void)
+{
+	git_filter custom = { GIT_FILTER_VERSION };
+
+	cl_git_pass(git_filter_register(
+		"custom", &custom, 42));
+
+	cl_assert_equal_i(1, filter_for("foo.custom", "crlf"));
+	cl_assert_equal_i(1, filter_for("foo.custom", "ident"));
+	cl_assert_equal_i(1, filter_for("foo.custom", "custom"));
+
+	git_filter_unregister("custom");
+}