nix build: Use Nix search path

That is, unless --file is specified, the Nix search path is
synthesized into an attribute set. Thus you can say

  $ nix build nixpkgs.hello

assuming $NIX_PATH contains an entry of the form "nixpkgs=...". This
is more verbose than

  $ nix build hello

but is less ambiguous.
This commit is contained in:
Eelco Dolstra 2016-08-23 17:11:19 +02:00
parent 22d6e31fc6
commit d74236d1f2
5 changed files with 57 additions and 13 deletions

View file

@ -379,9 +379,9 @@ void EvalState::addPrimOp(const string & name,
} }
void EvalState::getBuiltin(const string & name, Value & v) Value & EvalState::getBuiltin(const string & name)
{ {
v = *baseEnv.values[0]->attrs->find(symbols.create(name))->value; return *baseEnv.values[0]->attrs->find(symbols.create(name))->value;
} }
@ -462,7 +462,7 @@ void mkString(Value & v, const char * s)
} }
void mkString(Value & v, const string & s, const PathSet & context) Value & mkString(Value & v, const string & s, const PathSet & context)
{ {
mkString(v, s.c_str()); mkString(v, s.c_str());
if (!context.empty()) { if (!context.empty()) {
@ -473,6 +473,7 @@ void mkString(Value & v, const string & s, const PathSet & context)
v.string.context[n++] = dupString(i.c_str()); v.string.context[n++] = dupString(i.c_str());
v.string.context[n] = 0; v.string.context[n] = 0;
} }
return v;
} }

View file

@ -43,7 +43,7 @@ struct Env
}; };
void mkString(Value & v, const string & s, const PathSet & context = PathSet()); Value & mkString(Value & v, const string & s, const PathSet & context = PathSet());
void copyContext(const Value & v, PathSet & context); void copyContext(const Value & v, PathSet & context);
@ -108,6 +108,8 @@ public:
void addToSearchPath(const string & s); void addToSearchPath(const string & s);
SearchPath getSearchPath() { return searchPath; }
Path checkSourcePath(const Path & path); Path checkSourcePath(const Path & path);
/* Parse a Nix expression from the specified file. */ /* Parse a Nix expression from the specified file. */
@ -204,7 +206,7 @@ private:
public: public:
void getBuiltin(const string & name, Value & v); Value & getBuiltin(const string & name);
private: private:

View file

@ -128,9 +128,8 @@ static void getAllExprs(EvalState & state,
} }
attrs.insert(attrName); attrs.insert(attrName);
/* Load the expression on demand. */ /* Load the expression on demand. */
Value & vFun(*state.allocValue()); Value & vFun = state.getBuiltin("import");
Value & vArg(*state.allocValue()); Value & vArg(*state.allocValue());
state.getBuiltin("import", vFun);
mkString(vArg, path2); mkString(vArg, path2);
if (v.attrs->size() == v.attrs->capacity()) if (v.attrs->size() == v.attrs->capacity())
throw Error(format("too many Nix expressions in directory %1%") % path); throw Error(format("too many Nix expressions in directory %1%") % path);

View file

@ -9,6 +9,41 @@
namespace nix { namespace nix {
Value * MixInstallables::buildSourceExpr(EvalState & state)
{
Value * vRoot = state.allocValue();
if (file != "") {
Expr * e = state.parseExprFromFile(resolveExprPath(lookupFileArg(state, file)));
state.eval(e, *vRoot);
}
else {
/* Construct the installation source from $NIX_PATH. */
auto searchPath = state.getSearchPath();
state.mkAttrs(*vRoot, searchPath.size());
std::unordered_set<std::string> seen;
for (auto & i : searchPath) {
if (i.first == "") continue;
if (seen.count(i.first)) continue;
seen.insert(i.first);
if (!pathExists(i.second)) continue;
mkApp(*state.allocAttr(*vRoot, state.symbols.create(i.first)),
state.getBuiltin("import"),
mkString(*state.allocValue(), i.second));
}
vRoot->attrs->sort();
}
return vRoot;
}
UserEnvElems MixInstallables::evalInstallables(ref<Store> store) UserEnvElems MixInstallables::evalInstallables(ref<Store> store)
{ {
UserEnvElems res; UserEnvElems res;
@ -46,15 +81,12 @@ UserEnvElems MixInstallables::evalInstallables(ref<Store> store)
EvalState state({}, store); EvalState state({}, store);
Expr * e = state.parseExprFromFile(resolveExprPath(lookupFileArg(state, file))); auto vRoot = buildSourceExpr(state);
Value vRoot;
state.eval(e, vRoot);
std::map<string, string> autoArgs_; std::map<string, string> autoArgs_;
Bindings & autoArgs(*evalAutoArgs(state, autoArgs_)); Bindings & autoArgs(*evalAutoArgs(state, autoArgs_));
Value & v(*findAlongAttrPath(state, installable, autoArgs, vRoot)); Value & v(*findAlongAttrPath(state, installable, autoArgs, *vRoot));
state.forceValue(v); state.forceValue(v);
DrvInfos drvs; DrvInfos drvs;

View file

@ -21,10 +21,13 @@ struct UserEnvElem
typedef std::vector<UserEnvElem> UserEnvElems; typedef std::vector<UserEnvElem> UserEnvElems;
struct Value;
class EvalState;
struct MixInstallables : virtual Args struct MixInstallables : virtual Args
{ {
Strings installables; Strings installables;
Path file = "<nixpkgs>"; Path file;
MixInstallables() MixInstallables()
{ {
@ -33,6 +36,13 @@ struct MixInstallables : virtual Args
} }
UserEnvElems evalInstallables(ref<Store> store); UserEnvElems evalInstallables(ref<Store> store);
/* Return a value representing the Nix expression from which we
are installing. This is either the file specified by --file,
or an attribute set constructed from $NIX_PATH, e.g. { nixpkgs
= import ...; bla = import ...; }. */
Value * buildSourceExpr(EvalState & state);
}; };
} }