Add replaceRootSources app

src/apps/default.nix

@@ -32,6 +32,8 @@
 
     writeFlakeD2N = callPackageDream ./writeFlakeD2N {};
 
+    replaceRootSources = callPackageDream ./replaceRootSources {};
+
     flakeApps =
       b.mapAttrs (
         appName: app: {

src/apps/replaceRootSources/default.nix

@@ -0,0 +1,13 @@
+{
+  # from nixpkgs
+  python3,
+  writeScriptBin,
+  ...
+}: let
+  cliPython = python3.withPackages (ps: []);
+in
+  writeScriptBin
+  "replaceRootSources"
+  ''
+    ${cliPython}/bin/python ${./replaceRootSources.py} "$@"
+  ''

src/apps/replaceRootSources/replaceRootSources.py

@@ -0,0 +1,41 @@
+import sys
+import json
+
+def replace_root_sources(lock, newSource):
+
+    packages = lock['_generic']['packages']
+    sources = lock['sources']
+
+    for name, version in packages.items():
+
+        original = sources[name][version]
+
+        fixed = newSource
+
+        if 'dir' in original:
+            fixed['dir'] = original['dir']
+        elif 'relPath' in original:
+            fixed['dir'] = original['relPath']
+
+        sources[name][version] = fixed
+
+    lock['sources'] = sources
+
+    return lock
+
+
+if __name__ == '__main__':
+
+    lockFile = sys.argv[1]
+    newSourceFile = sys.argv[2]
+
+    with open(lockFile, "r") as f:
+        lock = json.load(f)
+
+    with open(newSourceFile, "r") as f:
+        newSource = json.load(f)
+
+    fixed = replace_root_sources(lock, newSource)
+
+    with open(lockFile, "w") as f:
+        json.dump(fixed, f, indent=2, sort_keys=True)