nightly vm test: the builder's meta build finds a prebuilt agent in an offline store

swarm-builder/src/nix_build.rs

@@ -705,6 +705,25 @@ mod tests {
         assert!(credential_helper().contains(&format!("${TOKEN_VAR}")));
     }
 
+    /// `nix/vm-tests/swarm-builder-offline.nix` runs a copy of the build command:
+    /// its credential helper and `nix build` flags. Change those there when this
+    /// fails.
+    #[test]
+    fn the_vm_test_copy_matches() {
+        assert_eq!(
+            credential_helper(),
+            "!f() { test \"$1\" = get || return 0; p=; h=; \
+             while IFS='=' read -r k v; do case \"$k\" in '') break ;; protocol) p=$v ;; host) h=$v ;; esac; done; \
+             test -n \"$SWARM_BUILDER_GIT_HOST\" && test \"$p\" = https && test \"$h\" = \"$SWARM_BUILDER_GIT_HOST\" \
+             && printf 'username=builder\\npassword=%s\\n' \"$SWARM_BUILDER_GIT_TOKEN\"; return 0; }; f"
+        );
+        assert_eq!(
+            BUILD_FLAGS.join(" "),
+            "build --no-link --print-out-paths --no-write-lock-file \
+             --option accept-flake-config false --print-build-logs"
+        );
+    }
+
     #[test]
     fn a_job_that_would_bend_the_reference_is_refused() {
         for bad in [