Commit graph

10 commits

Author SHA1 Message Date
Eelco Dolstra 8d4268d190 Improve error formatting
Changes:

* The divider lines are gone. These were in practice a bit confusing,
  in particular with --show-trace or --keep-going, since then there
  were multiple lines, suggesting a start/end which wasn't the case.

* Instead, multi-line error messages are now indented to align with
  the prefix (e.g. "error: ").

* The 'description' field is gone since we weren't really using it.

* 'hint' is renamed to 'msg' since it really wasn't a hint.

* The error is now printed *before* the location info.

* The 'name' field is no longer printed since most of the time it
  wasn't very useful since it was just the name of the exception (like
  EvalError). Ideally in the future this would be a unique, easily
  googleable error ID (like rustc).

* "trace:" is now just "…". This assumes error contexts start with
  something like "while doing X".

Example before:

  error: --- AssertionError ---------------------------------------------------------------------------------------- nix
  at: (7:7) in file: /home/eelco/Dev/nixpkgs/pkgs/applications/misc/hello/default.nix

       6|
       7|   x = assert false; 1;
        |       ^
       8|

  assertion 'false' failed
  ----------------------------------------------------- show-trace -----------------------------------------------------
  trace: while evaluating the attribute 'x' of the derivation 'hello-2.10'
  at: (192:11) in file: /home/eelco/Dev/nixpkgs/pkgs/stdenv/generic/make-derivation.nix

     191|         // (lib.optionalAttrs (!(attrs ? name) && attrs ? pname && attrs ? version)) {
     192|           name = "${attrs.pname}-${attrs.version}";
        |           ^
     193|         } // (lib.optionalAttrs (stdenv.hostPlatform != stdenv.buildPlatform && !dontAddHostSuffix && (attrs ? name || (attrs ? pname && attrs ? version)))) {

Example after:

  error: assertion 'false' failed

         at: (7:7) in file: /home/eelco/Dev/nixpkgs/pkgs/applications/misc/hello/default.nix

              6|
              7|   x = assert false; 1;
               |       ^
              8|

         … while evaluating the attribute 'x' of the derivation 'hello-2.10'

         at: (192:11) in file: /home/eelco/Dev/nixpkgs/pkgs/stdenv/generic/make-derivation.nix

            191|         // (lib.optionalAttrs (!(attrs ? name) && attrs ? pname && attrs ? version)) {
            192|           name = "${attrs.pname}-${attrs.version}";
               |           ^
            193|         } // (lib.optionalAttrs (stdenv.hostPlatform != stdenv.buildPlatform && !dontAddHostSuffix && (attrs ? name || (attrs ? pname && attrs ? version)))) {
2021-01-21 11:02:09 +01:00
Ben Burdette 1d43a6e123 use plain errPos instead of nixCode; fix tests 2020-06-23 15:30:13 -06:00
Eelco Dolstra 1fb762d11f Get rid of explicit ErrorInfo constructors 2020-06-15 14:06:58 +02:00
Ben Burdette 55eb717148 add pos to errorinfo, remove from hints 2020-05-08 18:18:28 -06:00
Eelco Dolstra 9af10b753c Bindings::get(): std::optional<Attr *> -> Attr *
Returning a nullable type in an optional is silly.
2020-02-13 17:15:05 +01:00
Eelco Dolstra 79142cbbe1 Bindings: Add convenience method for requiring an attribute
(cherry picked from commit fb692e5f7b)
2019-12-05 20:29:15 +01:00
Eelco Dolstra 0d118ef0c9 Bindings::get(): Add convenience method
This allows writing attribute lookups as

    if (auto name = value.attrs->get(state.sName))
      ...

(cherry picked from commit f216c76c56)
2019-12-05 20:29:00 +01:00
Tuomas Tynkkynen 056d28a601 libexpr: Don't create lots of temporary strings in Bindings::lexicographicOrder
Avoids ~180,000 string temporaries created when evaluating a headless
NixOS system.
2018-02-19 22:47:25 +02:00
Eelco Dolstra 54801ed6ad
Bindings: Add a method for iterating in lexicographically sorted order 2017-01-26 20:40:33 +01:00
Nicolas B. Pierron db21cfa688 Move attribute set data structures into their own header file.
This modification moves Attr and Bindings structures into their own header
file which is dedicated to the attribute set representation. The goal of to
isolate pieces of code which are related to the attribute set
representation. Thus future modifications of the attribute set
representation will only have to modify these files, and not every other
file across the evaluator.
2015-07-14 19:23:17 +02:00