Add 'third_party/nix/' from commit 'be66c7a6b24e3c3c6157fd37b86c7203d14acf10'

git-subtree-dir: third_party/nix
git-subtree-mainline: cf8cd640c1
git-subtree-split: be66c7a6b24e3c3c6157fd37b86c7203d14acf10

third_party/nix/tests/referrers.sh

@@ -0,0 +1,36 @@
+source common.sh
+
+clearStore
+
+max=500
+
+reference=$NIX_STORE_DIR/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+touch $reference
+(echo $reference && echo && echo 0) | nix-store --register-validity 
+
+echo "making registration..."
+
+set +x
+for ((n = 0; n < $max; n++)); do
+    storePath=$NIX_STORE_DIR/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa-$n
+    echo -n > $storePath
+    ref2=$NIX_STORE_DIR/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa-$((n+1))
+    if test $((n+1)) = $max; then
+        ref2=$reference
+    fi
+    echo $storePath; echo; echo 2; echo $reference; echo $ref2
+done > $TEST_ROOT/reg_info
+set -x
+
+echo "registering..."
+
+nix-store --register-validity < $TEST_ROOT/reg_info
+
+echo "collecting garbage..."
+ln -sfn $reference "$NIX_STATE_DIR"/gcroots/ref
+nix-store --gc
+
+if [ -n "$(type -p sqlite3)" -a "$(sqlite3 $NIX_STATE_DIR/db/db.sqlite 'select count(*) from Refs')" -ne 0 ]; then
+    echo "referrers not cleaned up"
+    exit 1
+fi