buildNimPackage: allow overriding nim package args

Without this, it's impossible to override the lockFile as the default
overrideAttrs is applied after the composition in buildNimPackage has
read the lock file and generated the nim flags from it.

1 files changed, 21 insertions, 0 deletions

diff --git a/pkgs/development/compilers/nim/build-nim-package.nix b/pkgs/development/compilers/nim/build-nim-package.nix
index 5085edf90a76..a22fb45b507b 100644
--- a/pkgs/development/compilers/nim/build-nim-package.nix
+++ b/pkgs/development/compilers/nim/build-nim-package.nix
@@ -7,6 +7,7 @@
 , nim_builder
 , defaultNimVersion ? 2
 , nimOverrides
+, buildNimPackage
 }:
 
 let
@@ -90,6 +91,7 @@ let
         , nativeBuildInputs ? [ ]
         , nimFlags ? [ ]
         , requiredNimVersion ? defaultNimVersion
+        , passthru ? { }
         , ...
         }:
         (if requiredNimVersion == 1 then {
@@ -102,6 +104,25 @@ let
           throw
             "requiredNimVersion ${toString requiredNimVersion} is not valid") // {
           nimFlags = lockFileNimFlags ++ nimFlags;
+          passthru = passthru // {
+            # allow overriding the result of buildNimPackageArgs before this composition is applied
+            # this allows overriding the lockFile for packages built using buildNimPackage
+            # this is adapted from mkDerivationExtensible in stdenv.mkDerivation
+            overrideNimAttrs = f0:
+              let
+                f = self: super:
+                  let x = f0 super;
+                  in
+                    if builtins.isFunction x
+                    then f0 self super
+                    else x;
+              in
+              buildNimPackage
+                (self:
+                  let super = (asFunc ((asFunc buildNimPackageArgs) self)) baseAttrs;
+                  in
+                    super // (if builtins.isFunction f0 || f0?__functor then f self super else f0));
+          };
         };
 
       attrs = postLock // finalOverride postLock;