Update terminology for block height and genesis block

book/src/terminology.md

@@ -20,7 +20,7 @@ A contiguous set of [entries](terminology.md#entry) on the ledger covered by a [
 
 ## block height
 
-The number of [blocks](terminology.md#block) beneath the current block. The first block after the [genesis block](terminology.md#genesis-block) has height zero.
+The number of [blocks](terminology.md#block) beneath the current block. The first block after the [genesis block](terminology.md#genesis-block) has height one.
 
 ## block id
 
@@ -96,7 +96,11 @@ A [ledger](terminology.md#ledger) derived from common entries but then diverged.
 
 ## genesis block
 
-The configuration file that prepares the [ledger](terminology.md#ledger) for the first [block](terminology.md#block).
+The first [block](terminology.md#block) in the chain.
+
+## genesis config
+
+The configuration file that prepares the [ledger](terminology.md#ledger) for the [genesis block](terminology.md#genesis-block).
 
 ## hash
 
@@ -114,10 +118,6 @@ A [public key](terminology.md#public-key) and corresponding [private key](termin
 
 A fractional [native token](terminology.md#native-token) with the value of 0.000000001 [sol](terminology.md#sol).
 
-## loader
-
-A [program](terminology.md#program) with the ability to interpret the binary encoding of other on-chain programs.
-
 ## leader
 
 The role of a [validator](terminology.md#validator) when it is appending [entries](terminology.md#entry) to the [ledger](terminology.md#ledger).
@@ -142,6 +142,10 @@ A [hash](terminology.md#hash) of the [validator's state](terminology.md#bank-sta
 
 A type of [client](terminology.md#client) that can verify it's pointing to a valid [cluster](terminology.md#cluster). It performs more ledger verification than a [thin client](terminology.md#thin-client) and less than a [validator](terminology.md#validator).
 
+## loader
+
+A [program](terminology.md#program) with the ability to interpret the binary encoding of other on-chain programs.
+
 ## lockout
 
 The duration of time for which a [validator](terminology.md#validator) is unable to [vote](terminology.md#ledger-vote) on another [fork](terminology.md#fork).

runtime/src/bank.rs

@@ -1682,6 +1682,15 @@ mod tests {
         assert_eq!(rent.lamports_per_byte_year, 5);
     }
 
+    #[test]
+    fn test_bank_block_height() {
+        let (genesis_block, _mint_keypair) = create_genesis_block(1);
+        let bank0 = Arc::new(Bank::new(&genesis_block));
+        assert_eq!(bank0.block_height(), 0);
+        let bank1 = Arc::new(new_from_parent(&bank0));
+        assert_eq!(bank1.block_height(), 1);
+    }
+
     #[test]
     fn test_bank_capitalization() {
         let bank = Arc::new(Bank::new(&GenesisBlock {