txdb: track newly discovered coins on unconfirm.

lib/wallet/txdb.js

@@ -1011,18 +1011,18 @@ class TXDB {
       if (!path)
         continue;
 
+      details.setOutput(i, path);
+
+      const credit = Credit.fromTX(tx, i, height);
+      credit.own = own;
+
       // If the first time we see a TX is in a block
       // (i.e. during a rescan) update the "unconfirmed" locked balance
       // before updating the "confirmed" locked balance.
       if (height !== -1)
-        this.lockBalances(state, output, path, -1);
+        this.lockBalances(state, credit, path, -1);
 
-      this.lockBalances(state, output, path, height);
-
-      details.setOutput(i, path);
-
-      const credit = Credit.fromTX(tx, i, height);
-      credit.own = own;
+      this.lockBalances(state, credit, path, height);
 
       state.tx(path, 1);
       state.coin(path, 1);
@@ -1196,8 +1196,6 @@ class TXDB {
       if (!path)
         continue;
 
-      this.lockBalances(state, output, path, height);
-
       details.setOutput(i, path);
 
       let credit = await this.getCredit(hash, i);
@@ -1217,9 +1215,11 @@ class TXDB {
         state.unconfirmed(path, credit.coin.value);
 
         // Add unconfirmed balances.
-        this.lockBalances(state, output, path, -1);
+        this.lockBalances(state, credit, path, -1);
       }
 
+      this.lockBalances(state, credit, path, height);
+
       // Credits spent in the mempool add an
       // undo coin for ease. If this credit is
       // spent in the mempool, we need to
@@ -1328,7 +1328,7 @@ class TXDB {
         state.coin(path, 1);
         state.unconfirmed(path, coin.value);
 
-        this.lockBalances(state, coin, path, height);
+        this.lockBalances(state, credit, path, height);
 
         if (block)
           state.confirmed(path, coin.value);
@@ -1515,7 +1515,7 @@ class TXDB {
   /**
    * Unconfirm a transaction. Necessary after a reorg.
    * @param {TXRecord} wtx
-   * @returns {Promise}
+   * @returns {Promise<Details>}
    */
 
   async disconnect(wtx, block) {
@@ -1528,6 +1528,8 @@ class TXDB {
 
     wtx.unsetBlock();
 
+    let own = false;
+
     if (!tx.isCoinbase()) {
       // We need to reconnect the coins. Start
       // by getting all of the undo coins we know
@@ -1549,7 +1551,7 @@ class TXDB {
         const path = await this.getPath(coin);
         assert(path);
 
-        this.lockBalances(state, coin, path, height);
+        this.lockBalances(state, credit, path, height);
 
         details.setInput(i, path, coin);
 
@@ -1559,6 +1561,7 @@ class TXDB {
         // as spent in the mempool instead.
         credit.spent = true;
         await this.saveCredit(b, credit, path);
+        own = true;
       }
     }
 
@@ -1571,12 +1574,42 @@ class TXDB {
       if (!path)
         continue;
 
-      const credit = await this.getCredit(hash, i);
+      let credit = await this.getCredit(hash, i);
 
       // Potentially update undo coin height.
+      // We may not have credit because it was spent in some unconfirmed tx,
+      // not because we just discovered.
       if (!credit) {
-        await this.updateSpentCoin(b, tx, i, height);
-        continue;
+        // If it is already spent and is ours, no need to add balances.
+        if (await this.updateSpentCoin(b, tx, i, height))
+          continue;
+
+        credit = Credit.fromTX(tx, i, -1);
+        credit.own = own;
+
+        // Is coin spent ? (tracking for double spends)
+        const spent = await this.getSpent(hash, i);
+
+        // If we were tracking coins as spent,
+        // it means it does not introduce any coin
+        // and does not affect the balance.
+        if (spent) {
+          credit.spent = true;
+          this.spendCredit(b, credit, tx, i);
+          details.setOutput(i, path);
+          continue;
+        }
+
+        // If it is not spent, then coin is in unconfirmed state.
+        state.coin(path, 1);
+        state.unconfirmed(path, output.value);
+
+        // will be subtracted below.
+        state.confirmed(path, output.value);
+
+        this.lockBalances(state, credit, path, -1);
+        // will be unlocked below
+        this.lockBalances(state, credit, path, height);
       }
 
       this.unlockBalances(state, credit, path, height);
@@ -1709,13 +1742,13 @@ class TXDB {
    * Inserting or confirming: TX outputs.
    * Removing or undoing: Coins spent by the wallet in tx inputs.
    * @param {State} state
-   * @param {Coin|Output} coin
+   * @param {Credit} credit
    * @param {Path} path
    * @param {Number} height
    */
 
-  lockBalances(state, coin, path, height) {
-    const {value, covenant} = coin;
+  lockBalances(state, credit, path, height) {
+    const {value, covenant} = credit.coin;
 
     switch (covenant.type) {
       case types.CLAIM:    // output is locked until REGISTER
@@ -3003,24 +3036,26 @@ class TXDB {
    * @param {TX} tx - Sending transaction.
    * @param {Number} index
    * @param {Number} height
-   * @returns {Promise}
+   * @returns {Promise<Boolean>}
    */
 
   async updateSpentCoin(b, tx, index, height) {
     const prevout = Outpoint.fromTX(tx, index);
     const spent = await this.getSpent(prevout.hash, prevout.index);
 
     if (!spent)
-      return;
+      return false;
 
+    // Was spent coin ours or are we tracking it for double spends.
     const coin = await this.getSpentCoin(spent, prevout);
 
     if (!coin)
-      return;
+      return false;
 
     coin.height = height;
 
     b.put(layout.d.encode(spent.hash, spent.index), coin.encode());
+    return true;
   }
 
   /**
@@ -3327,14 +3362,15 @@ class BalanceDelta {
  * @alias module:wallet.Credit
  * @property {Coin} coin
  * @property {Boolean} spent
+ * @property {Boolean} own
  */
 
 class Credit extends bio.Struct {
   /**
    * Create a credit.
    * @constructor
    * @param {Coin} coin
-   * @param {Boolean?} spent
+   * @param {Boolean} [spent = false]
    */
 
   constructor(coin, spent) {