Create an expectation by saying what the result should be.

parse letterChar "" "x" `shouldParse` 'x'

Create an expectation by saying that the parser should successfully parse a value and that the value should satisfy some predicate.

parse (many punctuationChar) "" "?!!" `parseSatisfies` ((== 3) . length)

Check that a parser succeeds on a given input.

parse (char 'x') "" `shouldSucceedOn` "x"

Check that a parser fails on a given input.

parse (char 'x') "" `shouldFailOn` "a"

Create an expectation that parser should fail producing certain ParseError. Use the err function from this module to construct a ParseError to compare with.

parse (char 'x') "" "b" `shouldFailWith` err posI (utok 'b' <> etok 'x')

Similar to shouldFailWith, but allows to check parsers that can report more than one parse error at a time.

Since: 2.0.0

Check that a parser fails and leaves a certain part of input unconsumed. Use it with functions like runParser' and runParserT' that support incremental parsing.

runParser' (many (char 'x') <* eof) (initialState "xxa")
  `failsLeaving` "a"

See also: initialState.

Check that a parser succeeds and leaves certain part of input unconsumed. Use it with functions like runParser' and runParserT' that support incremental parsing.

runParser' (many (char 'x')) (initialState "xxa")
  `succeedsLeaving` "a"

See also: initialState.

Given input for parsing, construct initial state for parser.

Given input for parsing, construct initial positional state.

Since: 2.0.0