ethblock: txs -> transactions (#694)

Using the same name as BlockBody to make them easily interchangeable -
* add a few inits

eth/common/eth_types.nim

@@ -171,7 +171,7 @@ type
 
   EthBlock* = object
     header*     : BlockHeader
-    txs*        : seq[Transaction]
+    transactions*: seq[Transaction]
     uncles*     : seq[BlockHeader]
     withdrawals*: Option[seq[Withdrawal]]   # EIP-4895
 
@@ -209,6 +209,10 @@ const
   EMPTY_UNCLE_HASH* = "1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347".toDigest
   EMPTY_CODE_HASH* = "c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470".toDigest
 
+template txs*(blk: EthBlock): seq[Transaction] =
+  # Legacy name emulation
+  blk.transactions
+
 when BlockNumber is int64:
   ## The goal of these templates is to make it easier to switch
   ## the block number type to a different representation
@@ -336,3 +340,11 @@ func hash*(a: EthAddress): Hash {.inline.} =
   copyMem(addr a2, unsafeAddr a[16], sizeof(a2))
 
   cast[Hash](a0 xor a1 xor uint64(a2))
+
+func init*(T: type EthBlock, header: sink BlockHeader, body: sink BlockBody): T =
+  T(
+    header: move(header),
+    transactions: move(body.transactions),
+    uncles: move(body.uncles),
+    withdrawals: move(body.withdrawals),
+  )

tests/common/test_common.nim

@@ -33,7 +33,7 @@ proc loadFile(x: int) =
     let header = r.read(EthHeader).header
     let body   = r.readRecordType(BlockBody, false)
 
-    let blk3 = EthBlock(header: header, txs: body.transactions, uncles: body.uncles)
+    let blk3 = EthBlock(header: header, transactions: body.transactions, uncles: body.uncles)
     let bytes3 = rlp.encode(blk3)
     check blk1 == blk3
     check bytes1 == bytes3