From 910dfdc41e134474b605ebd1f380e1b74d1a5e40 Mon Sep 17 00:00:00 2001 From: Silvan Mosberger Date: Mon, 21 Sep 2020 18:10:06 +0200 Subject: [PATCH] lib/modules: Evaluate single defs for readOnly error If multiple definitions are passed, this evaluates them all as if they were the only one, for a better error message. In particular this won't show module-internal properties like `_type = "override"` and co. --- lib/modules.nix | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/lib/modules.nix b/lib/modules.nix index de6fadbcb91..02a669df659 100644 --- a/lib/modules.nix +++ b/lib/modules.nix @@ -449,7 +449,13 @@ rec { # Handle properties, check types, and merge everything together. res = if opt.readOnly or false && length defs' > 1 then - throw "The option `${showOption loc}' is read-only, but it's set multiple times. Definition values:${showDefs defs'}" + let + # For a better error message, evaluate all readOnly definitions as + # if they were the only definition. + separateDefs = map (def: def // { + value = (mergeDefinitions loc opt.type [ def ]).mergedValue; + }) defs'; + in throw "The option `${showOption loc}' is read-only, but it's set multiple times. Definition values:${showDefs separateDefs}" else mergeDefinitions loc opt.type defs';