From dd341e602d5160fc621c0299179b91403756b61d Mon Sep 17 00:00:00 2001
From: Jon Atack <jon@atack.com>
Date: Sun, 25 Oct 2020 20:52:17 +0100
Subject: [PATCH] wallet: add sendtoaddress/sendmany explicit fee rate coverage

---
 test/functional/wallet_basic.py | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/test/functional/wallet_basic.py b/test/functional/wallet_basic.py
index 7edcf41beae..411ae3db29c 100755
--- a/test/functional/wallet_basic.py
+++ b/test/functional/wallet_basic.py
@@ -210,6 +210,8 @@ class WalletTest(BitcoinTestFramework):
         assert_equal(self.nodes[2].getbalance(), node_2_bal)
         node_0_bal = self.check_fee_amount(self.nodes[0].getbalance(), Decimal('20'), fee_per_byte, self.get_vsize(self.nodes[2].gettransaction(txid)['hex']))
 
+        self.log.info("Test sendmany")
+
         # Sendmany 10 BTC
         txid = self.nodes[2].sendmany('', {address: 10}, 0, "", [])
         self.nodes[2].generate(1)
@@ -226,7 +228,7 @@ class WalletTest(BitcoinTestFramework):
         assert_equal(self.nodes[2].getbalance(), node_2_bal)
         node_0_bal = self.check_fee_amount(self.nodes[0].getbalance(), node_0_bal + Decimal('10'), fee_per_byte, self.get_vsize(self.nodes[2].gettransaction(txid)['hex']))
 
-        # Sendmany with explicit fee (BTC/kB)
+        self.log.info("Test case-insensitive explicit fee rate (sendmany as BTC/kB)")
         # Throw if no conf_target provided
         assert_raises_rpc_error(-8, "Selected estimate_mode bTc/kB requires a fee rate to be specified in conf_target",
             self.nodes[2].sendmany,
@@ -252,7 +254,7 @@ class WalletTest(BitcoinTestFramework):
         node_0_bal += Decimal('10')
         assert_equal(self.nodes[0].getbalance(), node_0_bal)
 
-        # Sendmany with explicit fee (SAT/B)
+        self.log.info("Test case-insensitive explicit fee rate (sendmany as sat/B)")
         # Throw if no conf_target provided
         assert_raises_rpc_error(-8, "Selected estimate_mode sat/b requires a fee rate to be specified in conf_target",
             self.nodes[2].sendmany,
@@ -280,6 +282,12 @@ class WalletTest(BitcoinTestFramework):
         node_0_bal += Decimal('10')
         assert_equal(self.nodes[0].getbalance(), node_0_bal)
 
+        # Test setting explicit fee rate just below the minimum.
+        for unit, fee_rate in {"BTC/kB": 0.00000999, "sat/B": 0.99999999}.items():
+            self.log.info("Test sendmany raises 'fee rate too low' if conf_target {} and estimate_mode {} are passed".format(fee_rate, unit))
+            assert_raises_rpc_error(-6, "Fee rate (0.00000999 BTC/kB) is lower than the minimum fee rate setting (0.00001000 BTC/kB)",
+                self.nodes[2].sendmany, amounts={address: 10}, estimate_mode=unit, conf_target=fee_rate)
+
         self.start_node(3, self.nodes[3].extra_args)
         connect_nodes(self.nodes[0], 3)
         self.sync_all()
@@ -413,8 +421,7 @@ class WalletTest(BitcoinTestFramework):
             self.nodes[0].generate(1)
             self.sync_all(self.nodes[0:3])
 
-            # send with explicit btc/kb fee
-            self.log.info("test explicit fee (sendtoaddress as btc/kb)")
+            self.log.info("Test case-insensitive explicit fee rate (sendtoaddress as BTC/kB)")
             self.nodes[0].generate(1)
             self.sync_all(self.nodes[0:3])
             prebalance = self.nodes[2].getbalance()
@@ -447,9 +454,9 @@ class WalletTest(BitcoinTestFramework):
             fee = prebalance - postbalance - Decimal('1')
             assert_fee_amount(fee, tx_size, Decimal('0.00002500'))
 
-            # send with explicit sat/b fee
             self.sync_all(self.nodes[0:3])
-            self.log.info("test explicit fee (sendtoaddress as sat/b)")
+
+            self.log.info("Test case-insensitive explicit fee rate (sendtoaddress as sat/B)")
             self.nodes[0].generate(1)
             prebalance = self.nodes[2].getbalance()
             assert prebalance > 2
@@ -481,6 +488,12 @@ class WalletTest(BitcoinTestFramework):
             fee = prebalance - postbalance - Decimal('1')
             assert_fee_amount(fee, tx_size, Decimal('0.00002000'))
 
+            # Test setting explicit fee rate just below the minimum.
+            for unit, fee_rate in {"BTC/kB": 0.00000999, "sat/B": 0.99999999}.items():
+                self.log.info("Test sendtoaddress raises 'fee rate too low' if conf_target {} and estimate_mode {} are passed".format(fee_rate, unit))
+                assert_raises_rpc_error(-6, "Fee rate (0.00000999 BTC/kB) is lower than the minimum fee rate setting (0.00001000 BTC/kB)",
+                    self.nodes[2].sendtoaddress, address=address, amount=1, estimate_mode=unit, conf_target=fee_rate)
+
             # 2. Import address from node2 to node1
             self.nodes[1].importaddress(address_to_import)