lix/src/nix/edit.cc
2019-06-18 16:25:31 +02:00

76 lines
2 KiB
C++

#include "command.hh"
#include "shared.hh"
#include "eval.hh"
#include "attr-path.hh"
#include "progress-bar.hh"
#include <unistd.h>
using namespace nix;
struct CmdEdit : InstallableCommand
{
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();
auto v = installable->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", installable->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;
try {
lineno = std::stoi(std::string(pos, colon + 1));
} catch (std::invalid_argument e) {
throw Error("cannot parse line number '%s'", pos);
}
auto editor = getEnv("EDITOR", "cat");
auto args = tokenizeString<Strings>(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);
stopProgressBar();
execvp(args.front().c_str(), stringsToCharPtrs(args).data());
throw SysError("cannot run editor '%s'", editor);
}
};
static auto r1 = registerCommand<CmdEdit>("edit");