diff --git a/tests/repair.sh b/tests/repair.sh
index ec7ad5dca..ba019028d 100644
--- a/tests/repair.sh
+++ b/tests/repair.sh
@@ -13,14 +13,14 @@ hash=$(nix-hash $path2)
 chmod u+w $path2
 touch $path2/bad
 
-if nix-store --verify --check-contents -v; then
-    echo "nix-store --verify succeeded unexpectedly" >&2
-    exit 1
-fi
+(! nix-store --verify --check-contents -v)
 
 # The path can be repaired by rebuilding the derivation.
 nix-store --verify --check-contents --repair
 
+(! [ -e $path2/bad ])
+(! [ -w $path2 ])
+
 nix-store --verify-path $path2
 
 # Re-corrupt and delete the deriver. Now --verify --repair should
@@ -30,10 +30,7 @@ touch $path2/bad
 
 nix-store --delete $(nix-store -qd $path2)
 
-if nix-store --verify --check-contents --repair; then
-    echo "nix-store --verify --repair succeeded unexpectedly" >&2
-    exit 1
-fi
+(! nix-store --verify --check-contents --repair)
 
 nix-build dependencies.nix -o $TEST_ROOT/result --repair
 
diff --git a/tests/simple.sh b/tests/simple.sh
index 37631b648..15bd2bd16 100644
--- a/tests/simple.sh
+++ b/tests/simple.sh
@@ -10,13 +10,15 @@ outPath=$(nix-store -rvv "$drvPath")
 
 echo "output path is $outPath"
 
+(! [ -w $outPath ])
+
 text=$(cat "$outPath"/hello)
 if test "$text" != "Hello World!"; then exit 1; fi
 
 # Directed delete: $outPath is not reachable from a root, so it should
 # be deleteable.
 nix-store --delete $outPath
-if test -e $outPath/hello; then false; fi
+(! [ -e $outPath/hello ])
 
 outPath="$(NIX_REMOTE=local?store=/foo\&real=$TEST_ROOT/real-store nix-instantiate --readonly-mode hash-check.nix)"
 if test "$outPath" != "/foo/lfy1s6ca46rm5r6w4gg9hc0axiakjcnm-dependencies.drv"; then