From 33d58a90c26f9a62bb20863b767c0a505e6f997a Mon Sep 17 00:00:00 2001 From: Robert Hensing Date: Fri, 30 Jun 2023 01:29:11 +0200 Subject: [PATCH] toJSON: Add attribute path to trace --- doc/manual/src/release-notes/rl-next.md | 2 + src/libexpr/value-to-json.cc | 22 ++++++++-- tests/lang/eval-fail-toJSON.err.exp | 57 +++++++++++++++++++++++++ tests/lang/eval-fail-toJSON.nix | 10 +++++ 4 files changed, 88 insertions(+), 3 deletions(-) create mode 100644 tests/lang/eval-fail-toJSON.err.exp create mode 100644 tests/lang/eval-fail-toJSON.nix diff --git a/doc/manual/src/release-notes/rl-next.md b/doc/manual/src/release-notes/rl-next.md index 065364453..df30ce83d 100644 --- a/doc/manual/src/release-notes/rl-next.md +++ b/doc/manual/src/release-notes/rl-next.md @@ -6,3 +6,5 @@ [`builtins.flakeRefToString`](@docroot@/language/builtins.md#builtins-flakeRefToString), have been added. These functions are useful for converting between flake references encoded as attribute sets and URLs. + +- [`builtins.toJSON`](@docroot@/language/builtins.md#builtins-parseFlakeRef) now prints [--show-trace](@docroot@/command-ref/conf-file.html#conf-show-trace) items for the path in which it finds an evaluation error. diff --git a/src/libexpr/value-to-json.cc b/src/libexpr/value-to-json.cc index 4996a5bde..ac3986c87 100644 --- a/src/libexpr/value-to-json.cc +++ b/src/libexpr/value-to-json.cc @@ -43,6 +43,7 @@ json printValueAsJSON(EvalState & state, bool strict, break; case nNull: + // already initialized as null break; case nAttrs: { @@ -59,7 +60,13 @@ json printValueAsJSON(EvalState & state, bool strict, names.emplace(state.symbols[j.name]); for (auto & j : names) { Attr & a(*v.attrs->find(state.symbols.create(j))); - out[j] = printValueAsJSON(state, strict, *a.value, a.pos, context, copyToStore); + try { + out[j] = printValueAsJSON(state, strict, *a.value, a.pos, context, copyToStore); + } catch (Error & e) { + e.addTrace(state.positions[a.pos], + hintfmt("while evaluating attribute '%1%'", j)); + throw; + } } } else return printValueAsJSON(state, strict, *i->value, i->pos, context, copyToStore); @@ -68,8 +75,17 @@ json printValueAsJSON(EvalState & state, bool strict, case nList: { out = json::array(); - for (auto elem : v.listItems()) - out.push_back(printValueAsJSON(state, strict, *elem, pos, context, copyToStore)); + int i = 0; + for (auto elem : v.listItems()) { + try { + out.push_back(printValueAsJSON(state, strict, *elem, pos, context, copyToStore)); + } catch (Error & e) { + e.addTrace({}, + hintfmt("while evaluating list element at index %1%", i)); + throw; + } + i++; + } break; } diff --git a/tests/lang/eval-fail-toJSON.err.exp b/tests/lang/eval-fail-toJSON.err.exp new file mode 100644 index 000000000..4e618c203 --- /dev/null +++ b/tests/lang/eval-fail-toJSON.err.exp @@ -0,0 +1,57 @@ +error: + … while calling the 'toJSON' builtin + + at /pwd/lang/eval-fail-toJSON.nix:1:1: + + 1| builtins.toJSON { + | ^ + 2| a.b = [ + + … while evaluating attribute 'a' + + at /pwd/lang/eval-fail-toJSON.nix:2:3: + + 1| builtins.toJSON { + 2| a.b = [ + | ^ + 3| true + + … while evaluating attribute 'b' + + at /pwd/lang/eval-fail-toJSON.nix:2:3: + + 1| builtins.toJSON { + 2| a.b = [ + | ^ + 3| true + + … while evaluating list element at index 3 + + … while evaluating attribute 'c' + + at /pwd/lang/eval-fail-toJSON.nix:7:7: + + 6| { + 7| c.d = throw "hah no"; + | ^ + 8| } + + … while evaluating attribute 'd' + + at /pwd/lang/eval-fail-toJSON.nix:7:7: + + 6| { + 7| c.d = throw "hah no"; + | ^ + 8| } + + … while calling the 'throw' builtin + + at /pwd/lang/eval-fail-toJSON.nix:7:13: + + 6| { + 7| c.d = throw "hah no"; + | ^ + 8| } + + error: hah no diff --git a/tests/lang/eval-fail-toJSON.nix b/tests/lang/eval-fail-toJSON.nix new file mode 100644 index 000000000..8112e1c1f --- /dev/null +++ b/tests/lang/eval-fail-toJSON.nix @@ -0,0 +1,10 @@ +builtins.toJSON { + a.b = [ + true + false + "it's a bird" + { + c.d = throw "hah no"; + } + ]; +}