nim-eth/tests/rlp/test_api_usage.nim

{.used.}

import
  std/[math, unittest, strutils],
  stew/byteutils,
  ../../eth/rlp

proc q(s: string): string = "\"" & s & "\""
proc i(s: string): string = s.replace(" ").replace("\n")
proc inspectMatch(r: Rlp, s: string): bool = r.inspect.i == s.i

proc suite() =
  suite "test api usage":
    test "empty bytes are not a proper RLP":
      var rlp = rlpFromBytes seq[byte](@[])

      check:
        not rlp.hasData
        not rlp.isBlob
        not rlp.isList
        not rlp.isEmpty

      expect Exception:
        rlp.skipElem

      expect Exception:
        discard rlp.getType

      expect Exception:
        for e in rlp:
          discard e.getType

    test "you cannot finish a list without appending enough elements":
      var writer = initRlpList(3)
      writer.append "foo"
      writer.append "bar"

      expect Defect:
        discard writer.finish

    test "encode/decode object":
      type
        MyEnum = enum
          foo,
          bar

        MyObj = object
          a: array[3, char]
          b: int
          c: MyEnum

      var input: MyObj
      input.a = ['e', 't', 'h']
      input.b = 63
      input.c = bar

      var writer = initRlpWriter()
      writer.append(input)
      let bytes = writer.finish()
      var rlp = rlpFromBytes(bytes)

      var output = rlp.read(MyObj)
      check:
        input == output

    test "encode and decode lists":
      var writer = initRlpList(3)
      writer.append "foo"
      writer.append ["bar", "baz"]
      writer.append [30, 40, 50]

      var
        bytes = writer.finish
        rlp = rlpFromBytes bytes

      check:
        bytes.toHex == "d183666f6fc8836261728362617ac31e2832"
        rlp.inspectMatch """
          {
            "foo"
            {
              "bar"
              "baz"
            }
            {
              byte 30
              byte 40
              byte 50
            }
          }
        """

      bytes = encodeList(6000,
                        "Lorem ipsum dolor sit amet",
                        "Donec ligula tortor, egestas eu est vitae")

      rlp = rlpFromBytes bytes
      check:
        rlp.listLen == 3
        rlp.listElem(0).toInt(int) == 6000
        rlp.listElem(1).toString == "Lorem ipsum dolor sit amet"
        rlp.listElem(2).toString == "Donec ligula tortor, egestas eu est vitae"

      # test creating RLPs from other RLPs
      var list = rlpFromBytes encodeList(rlp.listELem(1), rlp.listELem(0))

      # test that iteration with enterList/skipElem works as expected
      doAssert list.enterList # We already know that we are working with a list
      check list.toString == "Lorem ipsum dolor sit amet"
      list.skipElem

      check list.toInt(int32) == 6000.int32
      var intVar: int
      list >> intVar
      check intVar == 6000

      check(not list.hasData)
      expect Exception: list.skipElem

    test "toBytes":
      let rlp = rlpFromHex("f2cb847f000001827666827666a040ef02798f211da2e8173d37f255be908871ae65060dbb2f77fb29c0421447f4845ab90b50")
      let tok = rlp.listElem(1).toBytes()
      check:
        tok.len == 32
        tok.toHex == "40ef02798f211da2e8173d37f255be908871ae65060dbb2f77fb29c0421447f4"

    test "nested lists":
      let listBytes = encode([[1, 2, 3], [5, 6, 7]])
      let listRlp = rlpFromBytes listBytes
      let sublistRlp0 = listRlp.listElem(0)
      let sublistRlp1 = listRlp.listElem(1)
      check sublistRlp0.listElem(0).toInt(int) == 1
      check sublistRlp0.listElem(1).toInt(int) == 2
      check sublistRlp0.listElem(2).toInt(int) == 3
      check sublistRlp1.listElem(0).toInt(int) == 5
      check sublistRlp1.listElem(1).toInt(int) == 6
      check sublistRlp1.listElem(2).toInt(int) == 7

    test "encoding length":
      let listBytes = encode([1,2,3,4,5])
      let listRlp = rlpFromBytes listBytes
      check listRlp.listLen == 5

      let emptyListBytes = encode ""
      check emptyListBytes.len == 1
      let emptyListRlp = rlpFromBytes emptyListBytes
      check emptyListRlp.blobLen == 0

    test "basic decoding":
      var rlp1 = rlpFromHex("856d6f6f7365")
      var rlp2 = rlpFromHex("0x856d6f6f7365")

      check:
        rlp1.inspect == q"moose"
        rlp2.inspect == q"moose"

    test "malformed/truncated RLP":
      var rlp = rlpFromHex("b8056d6f6f7365")
      expect MalformedRlpError:
        discard rlp.inspect

    test "encode byte arrays":
      var b1 = [byte(1), 2, 5, 7, 8]
      var b2 = [byte(6), 8, 12, 123]
      var b3 = @[byte(122), 56, 65, 12]

      let rlp = rlpFromBytes(encode((b1, b2, b3)))
      check:
        rlp.listLen == 3
        rlp.listElem(0).toBytes() == b1
        rlp.listElem(1).toBytes() == b2
        rlp.listElem(2).toBytes() == b3

        # The first byte here is the length of the datum (132 - 128 => 4)
        $(rlp.listElem(1).rawData) == "[132, 6, 8, 12, 123]"

    test "empty byte arrays":
      var
        rlp = rlpFromBytes rlp.encode("")
        b = rlp.toBytes
      check $b == "@[]"

    test "encode/decode floats":
      for f in [high(float64), low(float64), 0.1, 122.23,
                103487315.128934,
                1943935743563457201.391754032785692,
                0, -0,
                Inf, NegInf, NaN]:

        template isNaN(n): bool =
          classify(n) == fcNaN

        template chk(input) =
          let restored = decode(encode(input), float64)
          check restored == input or (input.isNaN and restored.isNaN)

        chk  f
        chk -f

    test "invalid enum":
      type
        MyEnum = enum
          foo,
          bar

      var writer = initRlpWriter()
      writer.append(2)
      writer.append(-1)
      let bytes = writer.finish()
      var rlp = rlpFromBytes(bytes)
      expect RlpTypeMismatch:
        discard rlp.read(MyEnum)
      rlp.skipElem()
      expect RlpTypeMismatch:
        discard rlp.read(MyEnum)

suite()