Merge #16978: test: Seed test RNG context for each test case, print seed

fae43a97ca947cd0802392e9bb86d9d0572c0fba test: Seed test RNG context for each test case, print seed (MarcoFalke)

Pull request description:

  Debugging failing unit tests is hard if the failure is non-deterministic and the seed is not known.

  Fix that by printing the seed and making it possible to set the seed from outside.

ACKs for top commit:
  davereikher:
    Tested ACK fae43a97ca947cd0802392e9bb86d9d0572c0fba

Tree-SHA512: 33d848dd1f4180d3664ecf60e9810c2a93590c05276b2c46b1e4fe6e376b45916a46b90c803bb602750ab666da3a05ce499e550024685a90b8cc38fab6667cb8

1 files changed, 14 insertions, 2 deletions

diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
index 5467cd6cce..1e2e059a56 100644
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -39,9 +39,21 @@ extern FastRandomContext g_insecure_rand_ctx;
  */
 extern bool g_mock_deterministic_tests;
 
-static inline void SeedInsecureRand(bool deterministic = false)
+enum class SeedRand {
+    ZEROS, //!< Seed with a compile time constant of zeros
+    SEED,  //!< Call the Seed() helper
+};
+
+/** Seed the given random ctx or use the seed passed in via an environment var */
+void Seed(FastRandomContext& ctx);
+
+static inline void SeedInsecureRand(SeedRand seed = SeedRand::SEED)
 {
-    g_insecure_rand_ctx = FastRandomContext(deterministic);
+    if (seed == SeedRand::ZEROS) {
+        g_insecure_rand_ctx = FastRandomContext(/* deterministic */ true);
+    } else {
+        Seed(g_insecure_rand_ctx);
+    }
 }
 
 static inline uint32_t InsecureRand32() { return g_insecure_rand_ctx.rand32(); }