Add option to disable import-from-derivation completely, even if the drv is already realized

1 files changed, 2 insertions, 0 deletions

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 5a570cefb2..93097f3d1b 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -59,6 +59,8 @@ void EvalState::realiseContext(const PathSet & context)
             drvs.insert(decoded.first + "!" + decoded.second);
     }
     if (!drvs.empty()) {
+        if (!settings.enableImportFromDerivation)
+            throw EvalError(format("attempted to realize ‘%1%’ during evaluation but 'allow-import-from-derivation' is false") % *(drvs.begin()));
         /* For performance, prefetch all substitute info. */
         PathSet willBuild, willSubstitute, unknown;
         unsigned long long downloadSize, narSize;