#include "command.hh" #include "shared.hh" #include "eval.hh" #include "attr-path.hh" #include <unistd.h> using namespace nix; struct CmdEdit : InstallablesCommand { std::string name() override { return "edit"; } std::string description() override { return "open the Nix expression of a Nix package in $EDITOR"; } Examples examples() override { return { Example{ "To open the Nix expression of the GNU Hello package:", "nix edit nixpkgs.hello" }, }; } void run(ref<Store> store) override { auto state = getEvalState(); for (auto & i : installables) { auto v = i->toValue(*state); Value * v2; try { auto dummyArgs = state->allocBindings(0); v2 = findAlongAttrPath(*state, "meta.position", *dummyArgs, *v); } catch (Error &) { throw Error("package ‘%s’ has no source location information", i->what()); } auto pos = state->forceString(*v2); debug("position is %s", pos); auto colon = pos.rfind(':'); if (colon == std::string::npos) throw Error("cannot parse meta.position attribute ‘%s’", pos); std::string filename(pos, 0, colon); int lineno = std::stoi(std::string(pos, colon + 1)); auto editor = getEnv("EDITOR", "cat"); Strings args{editor}; if (editor.find("emacs") != std::string::npos || editor.find("nano") != std::string::npos || editor.find("vim") != std::string::npos) args.push_back(fmt("+%d", lineno)); args.push_back(filename); execvp(editor.c_str(), stringsToCharPtrs(args).data()); throw SysError("cannot run editor ‘%s’", editor); } } }; static RegisterCommand r1(make_ref<CmdEdit>());