Support quoted attribute names in -A

This is requires if you have attribute names with dots in them.  So
you can now say:

  $ nix-instantiate '<nixos>' -A 'config.systemd.units."postgresql.service".text' --eval-only

Fixes #151.
This commit is contained in:
Eelco Dolstra 2013-11-18 10:21:12 +00:00
parent a478e8a7bb
commit 90b5e69284
3 changed files with 38 additions and 14 deletions

View file

@ -6,23 +6,44 @@
namespace nix {
static Strings parseAttrPath(const string & s)
{
Strings res;
string cur;
string::const_iterator i = s.begin();
while (i != s.end()) {
if (*i == '.') {
res.push_back(cur);
cur.clear();
} else if (*i == '"') {
++i;
while (1) {
if (i == s.end())
throw Error(format("missing closing quote in selection path `%1%'") % s);
if (*i == '"') break;
cur.push_back(*i++);
}
} else
cur.push_back(*i);
++i;
}
if (!cur.empty()) res.push_back(cur);
return res;
}
Value * findAlongAttrPath(EvalState & state, const string & attrPath,
Bindings & autoArgs, Value & vIn)
{
Strings tokens = tokenizeString<Strings>(attrPath, ".");
Strings tokens = parseAttrPath(attrPath);
Error attrError =
Error(format("attribute selection path `%1%' does not match expression") % attrPath);
string curPath;
Value * v = &vIn;
foreach (Strings::iterator, i, tokens) {
if (!curPath.empty()) curPath += ".";
curPath += *i;
/* Is *i an index (integer) or a normal attribute name? */
enum { apAttr, apIndex } apType = apAttr;
string attr = *i;
@ -43,11 +64,14 @@ Value * findAlongAttrPath(EvalState & state, const string & attrPath,
if (v->type != tAttrs)
throw TypeError(
format("the expression selected by the selection path `%1%' should be a set but is %2%")
% curPath % showType(*v));
% attrPath % showType(*v));
if (attr.empty())
throw Error(format("empty attribute name in selection path `%1%'") % attrPath);
Bindings::iterator a = v->attrs->find(state.symbols.create(attr));
if (a == v->attrs->end())
throw Error(format("attribute `%1%' in selection path `%2%' not found") % attr % curPath);
throw Error(format("attribute `%1%' in selection path `%2%' not found") % attr % attrPath);
v = &*a->value;
}
@ -56,10 +80,10 @@ Value * findAlongAttrPath(EvalState & state, const string & attrPath,
if (v->type != tList)
throw TypeError(
format("the expression selected by the selection path `%1%' should be a list but is %2%")
% curPath % showType(*v));
% attrPath % showType(*v));
if (attrIndex >= v->list.length)
throw Error(format("list index %1% in selection path `%2%' is out of range") % attrIndex % curPath);
throw Error(format("list index %1% in selection path `%2%' is out of range") % attrIndex % attrPath);
v = v->list.elems[attrIndex];
}

View file

@ -14,13 +14,13 @@ rec {
done < refs
'';
runtimeGraph = mkDerivation {
foo."bar.runtimeGraph" = mkDerivation {
name = "dependencies";
builder = builtins.toFile "build-graph-builder" "${printRefs}";
exportReferencesGraph = ["refs" (import ./dependencies.nix)];
};
buildGraph = mkDerivation {
foo."bar.buildGraph" = mkDerivation {
name = "dependencies";
builder = builtins.toFile "build-graph-builder" "${printRefs}";
exportReferencesGraph = ["refs" (import ./dependencies.nix).drvPath];

View file

@ -9,7 +9,7 @@ checkRef() {
# Test the export of the runtime dependency graph.
outPath=$(nix-build ./export-graph.nix -A runtimeGraph -o $TEST_ROOT/result)
outPath=$(nix-build ./export-graph.nix -A 'foo."bar.runtimeGraph"' -o $TEST_ROOT/result)
test $(nix-store -q --references $TEST_ROOT/result | wc -l) = 2 || fail "bad nr of references"
@ -20,7 +20,7 @@ for i in $(cat $outPath); do checkRef $i; done
nix-store --gc # should force rebuild of input-1
outPath=$(nix-build ./export-graph.nix -A buildGraph -o $TEST_ROOT/result)
outPath=$(nix-build ./export-graph.nix -A 'foo."bar.buildGraph"' -o $TEST_ROOT/result)
checkRef input-1
checkRef input-1.drv