wallet: check MTX for high and low fee errors along with policy limits

lib/wallet/wallet.js

@@ -3958,6 +3958,16 @@ class Wallet extends EventEmitter {
     if (tx.getWeight() > policy.MAX_TX_WEIGHT)
       throw new Error('TX exceeds policy weight.');
 
+    const minFee = policy.getMinFee(
+      mtx.getVirtualSize(),
+      this.network.minRelay
+    );
+    const fee = mtx.getFee();
+    if (fee < minFee)
+      throw new Error('Fee is below minimum relay limit.');
+    if (fee > minFee * 10000)
+      throw new Error('Fee exceeds absurd limit.');
+
     const ancestors = await this.getPendingAncestors(tx);
     if (ancestors.size + 1 > this.maxAncestors)
       throw new Error('TX exceeds maximum unconfirmed ancestors.');

test/wallet-auction-test.js

@@ -587,7 +587,7 @@ describe('Wallet Auction', function() {
           actions.push(['NONE', addr, 10000]);
         }
 
-        const batch = await wallet.sendBatch(actions, {hardFee: 10});
+        const batch = await wallet.sendBatch(actions, {hardFee: 1000});
 
         assert.strictEqual(batch.outputs.length, 11);
 
@@ -597,7 +597,7 @@ describe('Wallet Auction', function() {
 
         const newBal = await wallet.getBalance();
 
-        assert.strictEqual(oldBal.confirmed - newBal.confirmed, 100010);
+        assert.strictEqual(oldBal.confirmed - newBal.confirmed, 101000);
       });
 
       it('should verify expected name properties', async () => {

test/wallet-coinselection-test.js

@@ -102,5 +102,59 @@ describe('Wallet Coin Selection', function () {
       assert(rate < network.maxFeeRate);
       assert(fee > network.minRelay);
     });
+
+    it('should fail to pay absurd fee rate for small tx', async () => {
+      const address = await wallet.receiveAddress();
+      await assert.rejects(
+        wallet.send({
+          outputs: [{
+            address,
+            value: 5e6
+          }],
+          rate: 10001 * network.minRelay
+        }),
+        {message: 'Fee exceeds absurd limit.'}
+      );
+    });
+
+    it('should pay fee just under the absurd limit', async () => {
+      const address = await wallet.receiveAddress();
+      const tx = await wallet.send({
+        outputs: [{
+          address,
+          value: 5e6
+        }],
+        rate: 10000 * network.minRelay
+      });
+      const view = await wallet.getWalletCoinView(tx);
+      assert.strictEqual(tx.getRate(view), 10000 * network.minRelay);
+    });
+
+    it('should fail to pay too-low fee rate for small tx', async () => {
+      const address = await wallet.receiveAddress();
+      await assert.rejects(
+        wallet.send({
+          outputs: [{
+            address,
+            value: 5e6
+          }],
+          rate: network.minRelay - 1
+        }),
+        {message: 'Fee is below minimum relay limit.'}
+      );
+    });
+
+    it('should pay fee at the minimum relay limit', async () => {
+      const address = await wallet.receiveAddress();
+      const tx = await wallet.send({
+        outputs: [{
+          address,
+          value: 5e6
+        }],
+        rate: network.minRelay
+      });
+      const view = await wallet.getWalletCoinView(tx);
+      assert.strictEqual(tx.getRate(view), network.minRelay);
+    });
   });
 });