Also display suggestions for the commands using the eval cache

Make `nix build .#nix-armv8l-linux` work for example
This commit is contained in:
regnat 2022-03-04 09:44:00 +01:00
parent 2405bbbb5e
commit 98e361ad4c
4 changed files with 103 additions and 17 deletions

View file

@ -272,9 +272,9 @@ void completeFlakeRefWithFragment(
auto attr = root->findAlongAttrPath(attrPath);
if (!attr) continue;
for (auto & attr2 : attr->getAttrs()) {
for (auto & attr2 : (*attr)->getAttrs()) {
if (hasPrefix(attr2, lastAttr)) {
auto attrPath2 = attr->getAttrPath(attr2);
auto attrPath2 = (*attr)->getAttrPath(attr2);
/* Strip the attrpath prefix. */
attrPath2.erase(attrPath2.begin(), attrPath2.begin() + attrPathPrefix.size());
completions->add(flakeRefS + "#" + concatStringsSep(".", attrPath2));
@ -568,15 +568,22 @@ std::tuple<std::string, FlakeRef, InstallableValue::DerivationInfo> InstallableF
auto cache = openEvalCache(*state, lockedFlake);
auto root = cache->getRoot();
Suggestions suggestions;
for (auto & attrPath : getActualAttrPaths()) {
debug("trying flake output attribute '%s'", attrPath);
auto attr = root->findAlongAttrPath(
auto attrOrSuggestions = root->findAlongAttrPath(
parseAttrPath(*state, attrPath),
true
);
if (!attr) continue;
if (!attrOrSuggestions) {
suggestions += attrOrSuggestions.getSuggestions();
continue;
}
auto attr = *attrOrSuggestions;
if (!attr->isDerivation())
throw Error("flake output attribute '%s' is not a derivation", attrPath);
@ -591,7 +598,7 @@ std::tuple<std::string, FlakeRef, InstallableValue::DerivationInfo> InstallableF
return {attrPath, lockedFlake->flake.lockedRef, std::move(drvInfo)};
}
throw Error("flake '%s' does not provide attribute %s",
throw Error(suggestions, "flake '%s' does not provide attribute %s",
flakeRef, showAttrPaths(getActualAttrPaths()));
}
@ -642,7 +649,7 @@ InstallableFlake::getCursors(EvalState & state)
for (auto & attrPath : getActualAttrPaths()) {
auto attr = root->findAlongAttrPath(parseAttrPath(state, attrPath));
if (attr) res.push_back({attr, attrPath});
if (attr) res.push_back({*attr, attrPath});
}
return res;

View file

@ -406,6 +406,16 @@ Value & AttrCursor::forceValue()
return v;
}
Suggestions AttrCursor::getSuggestionsForAttr(Symbol name)
{
auto attrNames = getAttrs();
std::set<std::string> strAttrNames;
for (auto & name : attrNames)
strAttrNames.insert(std::string(name));
return Suggestions::bestMatches(strAttrNames, name);
}
std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(Symbol name, bool forceErrors)
{
if (root->db) {
@ -446,6 +456,11 @@ std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(Symbol name, bool forceErro
return nullptr;
//throw TypeError("'%s' is not an attribute set", getAttrPathStr());
for (auto & attr : *v.attrs) {
if (root->db)
root->db->setPlaceholder({cachedValue->first, attr.name});
}
auto attr = v.attrs->get(name);
if (!attr) {
@ -464,7 +479,7 @@ std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(Symbol name, bool forceErro
cachedValue2 = {root->db->setPlaceholder({cachedValue->first, name}), placeholder_t()};
}
return std::make_shared<AttrCursor>(
return make_ref<AttrCursor>(
root, std::make_pair(shared_from_this(), name), attr->value, std::move(cachedValue2));
}
@ -473,27 +488,31 @@ std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(std::string_view name)
return maybeGetAttr(root->state.symbols.create(name));
}
std::shared_ptr<AttrCursor> AttrCursor::getAttr(Symbol name, bool forceErrors)
ref<AttrCursor> AttrCursor::getAttr(Symbol name, bool forceErrors)
{
auto p = maybeGetAttr(name, forceErrors);
if (!p)
throw Error("attribute '%s' does not exist", getAttrPathStr(name));
return p;
return ref(p);
}
std::shared_ptr<AttrCursor> AttrCursor::getAttr(std::string_view name)
ref<AttrCursor> AttrCursor::getAttr(std::string_view name)
{
return getAttr(root->state.symbols.create(name));
}
std::shared_ptr<AttrCursor> AttrCursor::findAlongAttrPath(const std::vector<Symbol> & attrPath, bool force)
OrSuggestions<ref<AttrCursor>> AttrCursor::findAlongAttrPath(const std::vector<Symbol> & attrPath, bool force)
{
auto res = shared_from_this();
for (auto & attr : attrPath) {
res = res->maybeGetAttr(attr, force);
if (!res) return {};
auto child = res->maybeGetAttr(attr, force);
if (!child) {
auto suggestions = res->getSuggestionsForAttr(attr);
return OrSuggestions<ref<AttrCursor>>::failed(suggestions);
}
return res;
res = child;
}
return ref(res);
}
std::string AttrCursor::getString()

View file

@ -94,15 +94,17 @@ public:
std::string getAttrPathStr(Symbol name) const;
Suggestions getSuggestionsForAttr(Symbol name);
std::shared_ptr<AttrCursor> maybeGetAttr(Symbol name, bool forceErrors = false);
std::shared_ptr<AttrCursor> maybeGetAttr(std::string_view name);
std::shared_ptr<AttrCursor> getAttr(Symbol name, bool forceErrors = false);
ref<AttrCursor> getAttr(Symbol name, bool forceErrors = false);
std::shared_ptr<AttrCursor> getAttr(std::string_view name);
ref<AttrCursor> getAttr(std::string_view name);
std::shared_ptr<AttrCursor> findAlongAttrPath(const std::vector<Symbol> & attrPath, bool force = false);
OrSuggestions<ref<AttrCursor>> findAlongAttrPath(const std::vector<Symbol> & attrPath, bool force = false);
std::string getString();

View file

@ -40,4 +40,62 @@ public:
Suggestions& operator+=(const Suggestions & other);
};
// Either a value of type `T`, or some suggestions
template<typename T>
class OrSuggestions {
public:
using Raw = std::variant<T, Suggestions>;
Raw raw;
T* operator ->()
{
return &**this;
}
T& operator *()
{
if (auto elt = std::get_if<T>(&raw))
return *elt;
throw Error("Invalid access to a failed value");
}
operator bool() const noexcept
{
return std::holds_alternative<T>(raw);
}
OrSuggestions(T t)
: raw(t)
{
}
OrSuggestions()
: raw(Suggestions{})
{
}
static OrSuggestions<T> failed(const Suggestions & s)
{
auto res = OrSuggestions<T>();
res.raw = s;
return res;
}
static OrSuggestions<T> failed()
{
return OrSuggestions<T>::failed(Suggestions{});
}
const Suggestions & get_suggestions()
{
static Suggestions noSuggestions;
if (const auto & suggestions = std::get_if<Suggestions>(&raw))
return *suggestions;
else
return noSuggestions;
}
};
}