inst/tests/test7.r

In mslegrand/pegr: PEG PARSER

library(testthat)

context("Test7")


test_that("ADD_RULE",
{
  peg<-new.parser()
  peg<-add_rule(peg, "X<-x", des="A bad rule (I forgot quotes)")
  inspect_rule(peg, "X")->s1 
  answ1<-ruleStruct("X", "X<-x","A bad rule (I forgot quotes)" , NULL)
  expect_equal(s1,answ1)
  peg<-add_rule(peg, "X<-'x'", act="list('X')")
  inspect_rule(peg, "X")->s2
  answ2<-ruleStruct("X", "X<-'x'", NULL, "list('X')" )
  expect_equal(s2,answ2)
})

test_that("SET_RULE",
{
  peg<-new.parser()
  # Add rule A to recognize 'a' and return list('A') as it's value
  peg<-add_rule(peg, "A<-'a'", act="list('A')")
  value(apply_rule(peg, 'A', 'a', exe=TRUE))->v
  expect_equal(length(v),1)
  expect_equal(v[[1]], list("A")[[1]] )
  
  peg<-set_definition(peg, "A", "A<-'b'")
  # Now A will only recognize 'b', so it will now fail on input 'a'
  status(apply_rule(peg, 'A', 'a', exe=TRUE))->v
  expect_equal(v,FALSE)
  # However, A not recognizes b, but still returs list('A') as it's value
  value(apply_rule(peg, 'A', 'b', exe=TRUE))->v
  expect_equal(length(v),1)
  expect_equal(v[[1]], list("A")[[1]])
  
})

test_that("RULE_IDS",
{
  peg<-new.parser()
  peg<-add_rule(peg, "I<-'Ice'")
  peg<-add_rule(peg, "A<-'Age'")
  peg<-add_rule(peg, "S<-'Scrat'")
  rule_ids(peg)->s #c("A", "I", "S")
  expect_equal(s, c("A", "I", "S") )
})

test_that("QR",
{
  # A simple choice operator
  expect_equal(value(qp("'a' / 'b'")( "ab")), list(atom="a"))
  # A simple sequence operator
  expect_equal(value(qp("'a' 'b'")( "ab")), list(atom="a", atom="b"))
  # A combination of choice and sequence
  expect_equal(value(qp("('a'/'c') ('b' / 'd')")( "ab")), list(atom="a", atom="b"))
  qp("('a'/'c') ('b' / 'd')")( "ab")
  expect_equal(value(qp("('a'/'c') ('b' / 'd')")( "cd")), list(atom="c", atom="d"))
  # A lookahead not operator
  expect_equal(status(qp("'a' !'b'")( "ab" )), FALSE)
  # A lookahead not operator
  expect_equal(status(qp("'a' !'b'")( "ac" )), TRUE)
  expect_equal(value(qp("'a' !'b'")( "ac" )), list(atom="a"))
  # An lookahead and operator
  expect_equal(status(qp("'a' & 'b'")( "ab")), TRUE)
  expect_equal(value(qp("'a' & 'b'")( "ab")), list(atom="a"))
  expect_equal(status(qp("'a' & 'b'")( "ac")), FALSE)
  # An optional operator
  expect_equal(status(qp("'a' 'b'?")( "ab")), TRUE)
  expect_equal(value(qp("'a' 'b'?")( "ab")), list(atom="a", atom="b"))
  expect_equal(status(qp("'a' 'b'?")( "ab")), TRUE)
  expect_equal(value(qp("'a' 'b'?")( "ac")), list(atom="a"))
  expect_equal(status(qp("'a'? 'b'")( "ab")), TRUE)
  expect_equal(value(qp("'a'? 'b'")( "ab")), list(atom="a", atom="b"))
  expect_equal(status(qp("'a'? 'b'")( "ba")), TRUE)
  expect_equal(value(qp("'a'? 'b'")( "ba")), list( atom="b")) 
})