nix: Implement basic bash completion

This commit is contained in:
Eelco Dolstra 2020-05-10 20:32:21 +02:00
parent 14a3a62bfc
commit 91ddee6bf0
9 changed files with 95 additions and 4 deletions

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@ -11,6 +11,7 @@ makefiles = \
src/resolve-system-dependencies/local.mk \
scripts/local.mk \
corepkgs/local.mk \
misc/bash/local.mk \
misc/systemd/local.mk \
misc/launchd/local.mk \
misc/upstart/local.mk \

7
misc/bash/completion.sh Normal file
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@ -0,0 +1,7 @@
function _complete_nix {
while IFS= read -r line; do
COMPREPLY+=("$line")
done < <(NIX_GET_COMPLETIONS=$COMP_CWORD "${COMP_WORDS[@]}")
}
complete -F _complete_nix nix

1
misc/bash/local.mk Normal file
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@ -0,0 +1 @@
$(eval $(call install-file-as, $(d)/completion.sh, $(datarootdir)/bash-completion/completions/_nix3, 0644))

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@ -31,9 +31,17 @@ MixCommonArgs::MixCommonArgs(const string & programName)
.labels = {"name", "value"},
.handler = {[](std::string name, std::string value) {
try {
if (auto prefix = needsCompletion(name)) {
std::map<std::string, Config::SettingInfo> settings;
globalConfig.getSettings(settings);
for (auto & s : settings)
if (hasPrefix(s.first, *prefix))
completions->insert(s.first);
}
globalConfig.set(name, value);
} catch (UsageError & e) {
warn(e.what());
if (!completions)
warn(e.what());
}
}},
});

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@ -13,6 +13,19 @@ void Args::addFlag(Flag && flag_)
if (flag->shortName) shortFlags[flag->shortName] = flag;
}
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 +33,13 @@ 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>();
}
for (auto pos = cmdline.begin(); pos != cmdline.end(); ) {
auto arg = *pos;
@ -99,18 +119,32 @@ 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 anyNeedsCompletion = 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 (anyNeedsCompletion)
args.push_back("");
else
throw UsageError("flag '%s' requires %d argument(s)", name, flag.handler.arity);
} else {
if (needsCompletion(*pos))
anyNeedsCompletion = true;
args.push_back(*pos++);
}
args.push_back(*pos++);
}
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 +157,14 @@ 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;
}
@ -161,6 +203,10 @@ Args::Flag Args::Flag::mkHashTypeFlag(std::string && longName, HashType * ht)
.description = "hash algorithm ('md5', 'sha1', 'sha256', or 'sha512')",
.labels = {"hash-algo"},
.handler = {[ht](std::string s) {
if (auto prefix = needsCompletion(s))
for (auto & type : hashTypes)
if (hasPrefix(type, *prefix))
completions->insert(type);
*ht = parseHashType(s);
if (*ht == htUnknown)
throw UsageError("unknown hash type '%1%'", s);
@ -217,6 +263,11 @@ MultiCommand::MultiCommand(const Commands & commands)
{
expectedArgs.push_back(ExpectedArg{"command", 1, true, [=](std::vector<std::string> ss) {
assert(!command);
if (auto prefix = needsCompletion(ss[0])) {
for (auto & [name, command] : commands)
if (hasPrefix(name, *prefix))
completions->insert(name);
}
auto i = commands.find(ss[0]);
if (i == commands.end())
throw UsageError("'%s' is not a recognised command", ss[0]);

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@ -256,4 +256,8 @@ typedef std::vector<std::pair<std::string, std::string>> Table2;
void printTable(std::ostream & out, const Table2 & table);
extern std::shared_ptr<std::set<std::string>> completions;
std::optional<std::string> needsCompletion(std::string_view s);
}

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@ -16,6 +16,9 @@
namespace nix {
std::set<std::string> hashTypes = { "md5", "sha1", "sha256", "sha512" };
void Hash::init()
{
if (type == htMD5) hashSize = md5HashSize;

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@ -18,6 +18,8 @@ const int sha1HashSize = 20;
const int sha256HashSize = 32;
const int sha512HashSize = 64;
extern std::set<std::string> hashTypes;
extern const string base32Chars;
enum Base : int { Base64, Base32, Base16, SRI };

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@ -166,7 +166,21 @@ void mainWrapped(int argc, char * * argv)
NixArgs args;
args.parseCmdline(argvToStrings(argc, argv));
Finally printCompletions([&]()
{
if (completions) {
for (auto & s : *completions)
std::cout << s << "\n";
}
});
try {
args.parseCmdline(argvToStrings(argc, argv));
} catch (UsageError &) {
if (!completions) throw;
}
if (completions) return;
settings.requireExperimentalFeature("nix-command");