Merge #21377: Speedy trial support for versionbits

ffe33dfbd4c3b11e3475b022b6c1dd077613de79 chainparams: drop versionbits threshold to 90% for mainnnet and signet (Anthony Towns)
f054f6bcd2c2ce5fea84cf8681013f85a444e7ea versionbits: simplify state transitions (Anthony Towns)
55ac5f568a3b73d6f1ef4654617fb76e8bcbccdf versionbits: Add explicit NEVER_ACTIVE deployments (Anthony Towns)
dd07e6da48040dc7eae46bc7941db48d98a669fd fuzz: test versionbits delayed activation (Anthony Towns)
dd85d5411c1702c8ae259610fe55050ba212e21e tests: test versionbits delayed activation (Anthony Towns)
73d4a706393e6dbd6b6d6b6428f8d3233ac0a2d8 versionbits: Add support for delayed activation (Anthony Towns)
9e6b65f6fa205eee5c3b99343988adcb8d320460 tests: clean up versionbits test (Anthony Towns)
593274445004506c921d5d851361aefb3434d744 tests: test ComputeBlockVersion for all deployments (Anthony Towns)
63879f0a4760c0c0f784029849cb5d21ee088abb tests: pull ComputeBlockVersion test into its own function (Anthony Towns)

Pull request description:

  BIP9-based implementation of "speedy trial" activation specification, see https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2021-March/018583.html

  Edge cases are tested by fuzzing added in #21380.

ACKs for top commit:
  instagibbs:
    tACK https://github.com/bitcoin/bitcoin/pull/21377/commits/ffe33dfbd4c3b11e3475b022b6c1dd077613de79
  jnewbery:
    utACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79
  MarcoFalke:
    review ACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79 💈
  achow101:
    re-ACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79
  gmaxwell:
    ACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79
  benthecarman:
    ACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79
  Sjors:
    ACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79
  jonatack:
    Initial approach ACK ffe33dfbd4c3b11e3475b022b6c1dd077613de79 after a first pass of review, building and testing each commit, mostly looking at the changes and diffs. Will do a more high-level review iteration. A few minor comments follow to pick/choose/ignore.
  ariard:
    Code Review ACK ffe33df

Tree-SHA512: f79a7146b2450057ee92155cbbbcec12cd64334236d9239c6bd7d31b32eec145a9781c320f178da7b44ababdb8808b84d9d22a40e0851e229ba6d224e3be747c

1 files changed, 4 insertions, 4 deletions

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index 183fa50228..f27e9af0d9 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -1228,10 +1228,8 @@ static void BuriedForkDescPushBack(UniValue& softforks, const std::string &name,
 static void BIP9SoftForkDescPushBack(UniValue& softforks, const std::string &name, const Consensus::Params& consensusParams, Consensus::DeploymentPos id) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 {
     // For BIP9 deployments.
-    // Deployments (e.g. testdummy) with timeout value before Jan 1, 2009 are hidden.
-    // A timeout value of 0 guarantees a softfork will never be activated.
-    // This is used when merging logic to implement a proposed softfork without a specified deployment schedule.
-    if (consensusParams.vDeployments[id].nTimeout <= 1230768000) return;
+    // Deployments that are never active are hidden.
+    if (consensusParams.vDeployments[id].nStartTime == Consensus::BIP9Deployment::NEVER_ACTIVE) return;
 
     UniValue bip9(UniValue::VOBJ);
     const ThresholdState thresholdState = VersionBitsState(::ChainActive().Tip(), consensusParams, id, versionbitscache);
@@ -1261,6 +1259,7 @@ static void BIP9SoftForkDescPushBack(UniValue& softforks, const std::string &nam
         statsUV.pushKV("possible", statsStruct.possible);
         bip9.pushKV("statistics", statsUV);
     }
+    bip9.pushKV("min_activation_height", consensusParams.vDeployments[id].min_activation_height);
 
     UniValue rv(UniValue::VOBJ);
     rv.pushKV("type", "bip9");
@@ -1307,6 +1306,7 @@ RPCHelpMan getblockchaininfo()
                                     {RPCResult::Type::NUM_TIME, "start_time", "the minimum median time past of a block at which the bit gains its meaning"},
                                     {RPCResult::Type::NUM_TIME, "timeout", "the median time past of a block at which the deployment is considered failed if not yet locked in"},
                                     {RPCResult::Type::NUM, "since", "height of the first block to which the status applies"},
+                                    {RPCResult::Type::NUM, "min_activation_height", "minimum height of blocks for which the rules may be enforced"},
                                     {RPCResult::Type::OBJ, "statistics", "numeric statistics about BIP9 signalling for a softfork (only for \"started\" status)",
                                     {
                                         {RPCResult::Type::NUM, "period", "the length in blocks of the BIP9 signalling period"},