buildPythonPackage: overrideStdenvCompat: show position in its warning message (#481980)

pkgs/development/interpreters/python/mk-python-derivation.nix

@@ -418,7 +418,12 @@ lib.extendMkDerivation {
           optional-dependencies
           ;
         updateScript = nix-update-script { };
+        # __stdenvPythonCompat[Pos] attributes are here for overrideStdenvCompat in `python-packages-base.nix` to work.
+        # They are internal and subject to changes.
+        # TODO(@ShamrockLee): Remove when overrideStdenvCompat gets removed.
         ${if attrs ? stdenv then "__stdenvPythonCompat" else null} = attrs.stdenv;
+        ${if attrs ? stdenv then "__stdenvPythonCompatPos" else null} =
+          builtins.unsafeGetAttrPos "stdenv" attrs;
       }
       // attrs.passthru or { };
 

pkgs/development/interpreters/python/python-packages-base.nix

@@ -55,24 +55,29 @@ let
         args:
         let
           result = f args;
-          getName = x: x.pname or (lib.getName (x.name or "<unnamed>"));
-          applyMsgStdenvArg =
-            name:
-            lib.warnIf (lib.oldestSupportedReleaseIsAtLeast 2511) ''
-              ${name}: Passing `stdenv` directly to `buildPythonPackage` or `buildPythonApplication` is deprecated. You should use their `.override` function instead, e.g:
-                buildPythonPackage.override { stdenv = customStdenv; } { }
-            '';
+          handleStdenvArg =
+            attrs: attrName:
+            let
+              name = attrs.pname or (lib.getName (attrs.name or "<unnamed>"));
+              pos = attrs.__stdenvPythonCompatPos or (builtins.unsafeGetAttrPos attrName attrs);
+              msg = [
+                "${name}: Passing `stdenv` directly to `buildPythonPackage` or `buildPythonApplication` is deprecated. You should use their `.override` function instead, e.g:"
+                "  buildPythonPackage.override { stdenv = customStdenv; } { }"
+              ]
+              ++ lib.optionals (pos != null) [
+                "`stdenv` argument found at ${pos.file}:${toString pos.line}"
+              ];
+            in
+            lib.warnIf (lib.oldestSupportedReleaseIsAtLeast 2511) (lib.concatLines msg) attrs.${attrName};
         in
         if lib.isFunction args && result ? __stdenvPythonCompat then
           # Less reliable, as constructing with the wrong `stdenv` might lead to evaluation errors in the package definition.
-          f'.override { stdenv = applyMsgStdenvArg (getName result) result.__stdenvPythonCompat; } (
+          f'.override { stdenv = handleStdenvArg result "__stdenvPythonCompat"; } (
             finalAttrs: removeAttrs (args finalAttrs) [ "stdenv" ]
           )
         else if (!lib.isFunction args) && (args ? stdenv) then
           # More reliable, but only works when args is not `(finalAttrs: { })`
-          f'.override { stdenv = applyMsgStdenvArg (getName args) args.stdenv; } (
-            removeAttrs args [ "stdenv" ]
-          )
+          f'.override { stdenv = handleStdenvArg args "stdenv"; } (removeAttrs args [ "stdenv" ])
         else
           result
       )