libgit2-bug-find-similar

main.c

#include "stdio.h"
#include "git2.h"

int check_err(int code, const char* description) {
    fprintf(stderr, "%s failure %d\n", description, code);
    const git_error* err = git_error_last();
    fprintf(stderr, "libgit2 error was `%s` (klass=%d)", err->message, err->klass);
    return code;
}

int main(int argc, char** argv) {
    git_libgit2_init();

    git_repository* repo;

    int err = git_repository_open(&repo, "./minimal-git-repo");
    if (err != 0) return check_err(err, "git_repository_open");

    git_oid head;
    err = git_oid_fromstr(&head, "9ec10ec05ab48f65baf3bfb4a5fc61fd503a17f4");
    if (err != 0) return check_err(err, "git_oid_fromstr head");

    git_oid base;
    err = git_oid_fromstr(&base, "fb2f4327bee0557f6ebe21e9f97e2f8d03a36168");
    if (err != 0) return check_err(err, "git_oid_fromstr base");

    git_commit* head_commit;
    err = git_commit_lookup(&head_commit, repo, &head);
    if (err != 0) return check_err(err, "git_commit_lookup head");

    git_commit* base_commit;
    err = git_commit_lookup(&base_commit, repo, &base);
    if (err != 0) return check_err(err, "git_commit_lookup base");

    git_tree* head_tree;
    err = git_commit_tree(&head_tree, head_commit);
    if (err != 0) return check_err(err, "git_commit_tree head");

    git_tree* base_tree;
    err = git_commit_tree(&base_tree, base_commit);
    if (err != 0) return check_err(err, "git_commit_tree base");

    git_diff* diff;
    err = git_diff_tree_to_tree(&diff, repo, base_tree, head_tree, NULL);
    if (err != 0) return check_err(err, "git_diff_tree_to_tree");

    git_diff_find_options options;
    err = git_diff_find_options_init(&options, GIT_DIFF_FIND_OPTIONS_VERSION);
    if (err != 0) return check_err(err, "git_diff_find_options_init");

    options.flags = GIT_DIFF_FIND_RENAMES | GIT_DIFF_FIND_COPIES | GIT_DIFF_BREAK_REWRITES | GIT_DIFF_BREAK_REWRITES_FOR_RENAMES_ONLY;
    options.rename_threshold = 30;
    options.copy_threshold = 30;
    options.rename_limit = 1000000;

    err = git_diff_find_similar(diff, &options);
    if (err != 0) return check_err(err, "git_diff_find_similar");

    // skip proper cleanup, this is just a testcase

    return 0;
}

Makefile

libgit2:
	git clone https://github.com/libgit2/libgit2
	mkdir libgit2-build
	cd libgit2-build && cmake ../libgit2 && cmake --build .

testcase:
	gcc -I libgit2/include/ -L libgit2-build/ main.c -l git2 -o main
	LD_LIBRARY_PATH=libgit2-build/ ./main