From eac5841970737b799c55ec78f6ace6d80762ff04 Mon Sep 17 00:00:00 2001 From: Shea Levy Date: Thu, 15 May 2014 11:30:46 -0400 Subject: [PATCH] Provide a more useful error message when a dynamic attr lookup fails --- src/libexpr/eval.cc | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index 0f7e8e385..81abe5b61 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -757,8 +757,16 @@ void ExprSelect::eval(EvalState & state, Env & env, Value & v) } } else { state.forceAttrs(*vAttrs, pos); - if ((j = vAttrs->attrs->find(name)) == vAttrs->attrs->end()) - throwEvalError("attribute `%1%' missing, at %2%", showAttrPath(attrPath), pos); + if ((j = vAttrs->attrs->find(name)) == vAttrs->attrs->end()) { + AttrPath staticPath; + AttrPath::const_iterator j; + for (j = attrPath.begin(); j != i; ++j) + staticPath.push_back(AttrName(getName(*j, state, env))); + staticPath.push_back(AttrName(getName(*j, state, env))); + for (j = j + 1; j != attrPath.end(); ++j) + staticPath.push_back(*j); + throwEvalError("attribute `%1%' missing, at %2%", showAttrPath(staticPath), pos); + } } vAttrs = j->value; pos2 = j->pos;