diff options
Diffstat (limited to 'src/libutil/args.cc')
-rw-r--r-- | src/libutil/args.cc | 139 |
1 files changed, 119 insertions, 20 deletions
diff --git a/src/libutil/args.cc b/src/libutil/args.cc index 1f0e4f803..986c5d1cd 100644 --- a/src/libutil/args.cc +++ b/src/libutil/args.cc @@ -1,6 +1,8 @@ #include "args.hh" #include "hash.hh" +#include <glob.h> + namespace nix { void Args::addFlag(Flag && flag_) @@ -13,6 +15,20 @@ void Args::addFlag(Flag && flag_) if (flag->shortName) shortFlags[flag->shortName] = flag; } +bool pathCompletions = false; +std::shared_ptr<std::set<std::string>> completions; + +std::string completionMarker = "___COMPLETE___"; + +std::optional<std::string> needsCompletion(std::string_view s) +{ + if (!completions) return {}; + auto i = s.find(completionMarker); + if (i != std::string::npos) + return std::string(s.begin(), i); + return {}; +} + void Args::parseCmdline(const Strings & _cmdline) { Strings pendingArgs; @@ -20,6 +36,14 @@ void Args::parseCmdline(const Strings & _cmdline) Strings cmdline(_cmdline); + if (auto s = getEnv("NIX_GET_COMPLETIONS")) { + size_t n = std::stoi(*s); + assert(n > 0 && n <= cmdline.size()); + *std::next(cmdline.begin(), n - 1) += completionMarker; + completions = std::make_shared<decltype(completions)::element_type>(); + verbosity = lvlError; + } + for (auto pos = cmdline.begin(); pos != cmdline.end(); ) { auto arg = *pos; @@ -63,7 +87,7 @@ void Args::printHelp(const string & programName, std::ostream & out) for (auto & exp : expectedArgs) { std::cout << renderLabels({exp.label}); // FIXME: handle arity > 1 - if (exp.arity == 0) std::cout << "..."; + if (exp.handler.arity == ArityAny) std::cout << "..."; if (exp.optional) std::cout << "?"; } std::cout << "\n"; @@ -99,18 +123,32 @@ bool Args::processFlag(Strings::iterator & pos, Strings::iterator end) auto process = [&](const std::string & name, const Flag & flag) -> bool { ++pos; std::vector<std::string> args; + bool anyCompleted = false; for (size_t n = 0 ; n < flag.handler.arity; ++n) { if (pos == end) { if (flag.handler.arity == ArityAny) break; throw UsageError("flag '%s' requires %d argument(s)", name, flag.handler.arity); } + if (flag.completer) + if (auto prefix = needsCompletion(*pos)) { + anyCompleted = true; + flag.completer(n, *prefix); + } args.push_back(*pos++); } - flag.handler.fun(std::move(args)); + if (!anyCompleted) + flag.handler.fun(std::move(args)); return true; }; if (string(*pos, 0, 2) == "--") { + if (auto prefix = needsCompletion(*pos)) { + for (auto & [name, flag] : longFlags) { + if (!hiddenCategories.count(flag->category) + && hasPrefix(name, std::string(*prefix, 2))) + completions->insert("--" + name); + } + } auto i = longFlags.find(string(*pos, 2)); if (i == longFlags.end()) return false; return process("--" + i->first, *i->second); @@ -123,6 +161,14 @@ bool Args::processFlag(Strings::iterator & pos, Strings::iterator end) return process(std::string("-") + c, *i->second); } + if (auto prefix = needsCompletion(*pos)) { + if (prefix == "-") { + completions->insert("--"); + for (auto & [flag, _] : shortFlags) + completions->insert(std::string("-") + flag); + } + } + return false; } @@ -138,12 +184,17 @@ bool Args::processArgs(const Strings & args, bool finish) bool res = false; - if ((exp.arity == 0 && finish) || - (exp.arity > 0 && args.size() == exp.arity)) + if ((exp.handler.arity == ArityAny && finish) || + (exp.handler.arity != ArityAny && args.size() == exp.handler.arity)) { std::vector<std::string> ss; - for (auto & s : args) ss.push_back(s); - exp.handler(std::move(ss)); + for (const auto &[n, s] : enumerate(args)) { + ss.push_back(s); + if (exp.completer) + if (auto prefix = needsCompletion(s)) + exp.completer(n, *prefix); + } + exp.handler.fun(ss); expectedArgs.pop_front(); res = true; } @@ -154,6 +205,13 @@ bool Args::processArgs(const Strings & args, bool finish) return res; } +static void hashTypeCompleter(size_t index, std::string_view prefix) +{ + for (auto & type : hashTypes) + if (hasPrefix(type, prefix)) + completions->insert(type); +} + Args::Flag Args::Flag::mkHashTypeFlag(std::string && longName, HashType * ht) { return Flag { @@ -162,7 +220,8 @@ Args::Flag Args::Flag::mkHashTypeFlag(std::string && longName, HashType * ht) .labels = {"hash-algo"}, .handler = {[ht](std::string s) { *ht = parseHashType(s); - }} + }}, + .completer = hashTypeCompleter }; } @@ -174,10 +233,42 @@ Args::Flag Args::Flag::mkHashTypeOptFlag(std::string && longName, std::optional< .labels = {"hash-algo"}, .handler = {[oht](std::string s) { *oht = std::optional<HashType> { parseHashType(s) }; - }} + }}, + .completer = hashTypeCompleter }; } +static void completePath(std::string_view prefix, bool onlyDirs) +{ + pathCompletions = true; + glob_t globbuf; + int flags = GLOB_NOESCAPE | GLOB_TILDE; + #ifdef GLOB_ONLYDIR + if (onlyDirs) + flags |= GLOB_ONLYDIR; + #endif + if (glob((std::string(prefix) + "*").c_str(), flags, nullptr, &globbuf) == 0) { + for (size_t i = 0; i < globbuf.gl_pathc; ++i) { + if (onlyDirs) { + auto st = lstat(globbuf.gl_pathv[i]); + if (!S_ISDIR(st.st_mode)) continue; + } + completions->insert(globbuf.gl_pathv[i]); + } + globfree(&globbuf); + } +} + +void completePath(size_t, std::string_view prefix) +{ + completePath(prefix, false); +} + +void completeDir(size_t, std::string_view prefix) +{ + completePath(prefix, true); +} + Strings argvToStrings(int argc, char * * argv) { Strings args; @@ -225,18 +316,26 @@ void Command::printHelp(const string & programName, std::ostream & out) MultiCommand::MultiCommand(const Commands & commands) : commands(commands) { - expectedArgs.push_back(ExpectedArg{"command", 1, true, [=](std::vector<std::string> ss) { - assert(!command); - auto cmd = ss[0]; - if (auto alias = get(deprecatedAliases, cmd)) { - warn("'%s' is a deprecated alias for '%s'", cmd, *alias); - cmd = *alias; - } - auto i = commands.find(cmd); - if (i == commands.end()) - throw UsageError("'%s' is not a recognised command", cmd); - command = {cmd, i->second()}; - }}); + expectArgs({ + .label = "command", + .optional = true, + .handler = {[=](std::string s) { + assert(!command); + if (auto alias = get(deprecatedAliases, s)) { + warn("'%s' is a deprecated alias for '%s'", s, *alias); + s = *alias; + } + if (auto prefix = needsCompletion(s)) { + for (auto & [name, command] : commands) + if (hasPrefix(name, *prefix)) + completions->insert(name); + } + auto i = commands.find(s); + if (i == commands.end()) + throw UsageError("'%s' is not a recognised command", s); + command = {s, i->second()}; + }} + }); categories[Command::catDefault] = "Available commands"; } |