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Diffstat (limited to 'spec/practical_spec.cr')
| -rw-r--r-- | spec/practical_spec.cr | 146 |
1 files changed, 0 insertions, 146 deletions
diff --git a/spec/practical_spec.cr b/spec/practical_spec.cr deleted file mode 100644 index f992a15..0000000 --- a/spec/practical_spec.cr +++ /dev/null @@ -1,146 +0,0 @@ -require "./spec_helper" - -include Parcom - -describe "Text surrounded by whitespace" do - ws_char = Parser(Char, Char).satisfy { |c| c.whitespace? } - normal_char = Parser(Char, Char).satisfy { |c| !c.whitespace? } - - word = normal_char.some.map { |cs| cs.join } - ws = ws_char.some - - words = ws.optional >> word.sep_by(ws) << ws.optional - - good_strings = { - "test with no trailing whitespace", - " test with whitespace in the front", - "test with whitespace in the back", - " test surrounded by whitespace ", - } - - good_strings.each do |s| - tokens = Tokens.from_string(s) - result = words.parse(tokens) - - result.value.should eq(s.strip.split(/\s+/)) - result.tokens.empty?.should be_true - end - - bad_strings = { - "", - " \t \n ", - } - - bad_strings.each do |s| - tokens = Tokens.from_string(s) - expect_raises(ParserFail) { words.parse(tokens) } - end -end - -enum BFOpType - BFAdd - BFShift - BFByteIn - BFByteOut - BFLoopStart - BFLoopEnd -end - -alias BFOp = { - type: BFOpType, - amount: Int32, -} - -describe "brainfuck parser" do - # From https://esolangs.org/wiki/Brainfuck#Examples - hello_world_str = "1 +++++ +++ Set Cell #0 to 8 - 2 [ - 3 >++++ Add 4 to Cell #1; this will always set Cell #1 to 4 - 4 [ as the cell will be cleared by the loop - 5 >++ Add 4*2 to Cell #2 - 6 >+++ Add 4*3 to Cell #3 - 7 >+++ Add 4*3 to Cell #4 - 8 >+ Add 4 to Cell #5 - 9 <<<<- Decrement the loop counter in Cell #1 -10 ] Loop till Cell #1 is zero -11 >+ Add 1 to Cell #2 -12 >+ Add 1 to Cell #3 -13 >- Subtract 1 from Cell #4 -14 >>+ Add 1 to Cell #6 -15 [<] Move back to the first zero cell you find; this will -16 be Cell #1 which was cleared by the previous loop -17 <- Decrement the loop Counter in Cell #0 -18 ] Loop till Cell #0 is zero -19 -20 The result of this is: -21 Cell No : 0 1 2 3 4 5 6 -22 Contents: 0 0 72 104 88 32 8 -23 Pointer : ^ -24 -25 >>. Cell #2 has value 72 which is 'H' -26 >---. Subtract 3 from Cell #3 to get 101 which is 'e' -27 +++++ ++..+++. Likewise for 'llo' from Cell #3 -28 >>. Cell #5 is 32 for the space -29 <-. Subtract 1 from Cell #4 for 87 to give a 'W' -30 <. Cell #3 was set to 'o' from the end of 'Hello' -31 +++.----- -.----- ---. Cell #3 for 'rl' and 'd' -32 >>+. Add 1 to Cell #5 gives us an exclamation point -33 >++. And finally a newline from Cell #6" - - bf_chars = Set{'+', '-', '.', ',', '<', '>', '[', ']'} - other = Parser(Char, Char).satisfy { |c| !bf_chars.includes?(c) } - bf_char = Parser(Char, Char).satisfy { |c| bf_chars.includes?(c) } - - char_body = bf_char.some.sep_by(other.some).map(&.flatten) - just_bf_chars = other.many >> char_body << other.many - - loop_start = Parser(Char, Char).token('[').map do |_| - {type: BFOpType::BFLoopStart, amount: 0} - end - - loop_end = Parser(Char, Char).token(']').map do |_| - {type: BFOpType::BFLoopEnd, amount: 0} - end - - read_block = Parser(Char, Char).token(',').some.map do |cs| - {type: BFOpType::BFByteIn, amount: cs.size} - end - - write_block = Parser(Char, Char).token('.').some.map do |cs| - {type: BFOpType::BFByteOut, amount: cs.size} - end - - shift_block = (Parser.token('<') | Parser.token('>')).some.map do |cs| - left_count = cs.count { |c| c == '<' } - right_count = cs.size - left_count - {type: BFOpType::BFShift, amount: right_count - left_count} - end - - add_block = (Parser.token('+') | Parser.token('-')).some.map do |cs| - minus_count = cs.count { |c| c == '-' } - plus_count = cs.size - minus_count - {type: BFOpType::BFAdd, amount: plus_count - minus_count} - end - - bf_token = Parser.first_of([ - loop_start, - loop_end, - read_block, - write_block, - shift_block, - add_block, - ]) - - tokenizer = Parser(Char, Array(BFOp)).new("BF tokenizer") do |tokens| - result = just_bf_chars.parse(tokens) - puts result - chars = Tokens.new(result.value) - bf_token.some.parse(chars) - end - - tokens = Tokens.from_string(hello_world_str) - result = tokenizer.parse(tokens) - puts result - # TODO: find a good way to verify this result -end - |