dart: Spoof Git dependency version checks

pkgs/build-support/dart/build-dart-application/hooks/dart-config-hook.sh

···
     echo "Executing dartConfigHook"
 
     echo "Installing dependencies"
-    eval "$pubGetScript" --offline
+    eval doPubGet "$pubGetScript" --offline
 
     echo "Finished dartConfigHook"
 }

pkgs/build-support/dart/fetch-dart-deps/default.nix

···
 { stdenvNoCC
 , lib
 , makeSetupHook
+, writeShellScriptBin
 , dart
 , git
 , cacert
···
     '';
   } // buildDrvInheritArgs);
 
+  # As of Dart 3.0.0, Pub checks the revision of cached Git-sourced packages.
+  # Git must be wrapped to return a positive result, as the real .git directory is wiped
+  # to produce a deteministic dependency derivation output.
+  # https://github.com/dart-lang/pub/pull/3791/files#diff-1639c4669c428c26e68cfebd5039a33f87ba568795f2c058c303ca8528f62b77R631
+  gitSourceWrapper = writeShellScriptBin "git" ''
+    args=("$@")
+    if [[ "''${args[0]}" == "rev-list" && "''${args[1]}" == "--max-count=1" ]]; then
+      revision="''${args[''${#args[@]}-1]}"
+      echo "$revision"
+    else
+      ${git}/bin/git "''${args[@]}"
+    fi
+  '';
+
   hook = (makeSetupHook {
     # The setup hook should not be part of the fixed-output derivation.
     # Updates to the hook script should not change vendor hashes, and it won't
     # work at all anyway due to https://github.com/NixOS/nix/issues/6660.
     name = "${name}-dart-deps-setup-hook";
-    substitutions = { inherit deps; };
+    substitutions = { inherit gitSourceWrapper deps; };
     propagatedBuildInputs = [ dart git ];
     passthru = {
       files = deps.outPath;

pkgs/build-support/dart/fetch-dart-deps/setup-hook.sh

···
         exit 1
     fi
 }
+
+# Performs the given pub get command with an appropriate environment.
+doPubGet() {
+    PATH="@gitSourceWrapper@/bin:$PATH" "$@"
+}

pkgs/build-support/flutter/default.nix

···
 
       mkdir -p build/flutter_assets/fonts
 
-      flutter packages get --offline -v
+      doPubGet flutter pub get --offline -v
       flutter build linux -v --release --split-debug-info="$debug" ${builtins.concatStringsSep " " (map (flag: "\"${flag}\"") finalAttrs.flutterBuildFlags)}
 
       runHook postBuild

pkgs/misc/dart-sass-embedded/default.nix

···
 
   configurePhase = ''
     runHook preConfigure
-    dart pub get --offline
+    doPubGet dart pub get --offline
     mkdir build
     ln -s ${embedded-protocol} build/embedded-protocol
     runHook postConfigure