Modulehspec-attoparsec-0.1.0.2Haskell2010

Test.Hspec.Attoparsec

Utility functions for testing attoparsec parsers, each one providing an example of how to use it.

Contents

Equality-based combinator
Predicate-based combinator
Inspecting the result
Inspecting unconsumed input
The Source class, connecting parsers and inputs
The Leftover class, letting us inspect unconsumed input

Synopsis

value shouldParse
value parseSatisfies
value shouldSucceedOn
value shouldFailOn
value leavesUnconsumed
class Source
class Leftover

Packagehspec-attoparsec-0.1.0.2
Exports7
LanguageHaskell2010
LicenceBSD-3-Clause
SourceAttoparsec.hs

Equality-based combinator

valueshouldParse :: (Eq a, Show a) => Either String a -> a -> Expectation

Source#

Create an expectation by saying what the result should be. Intended to be used with ~> as follows:

  "<!-- foo -->" ~> htmlCommentParser
    `shouldParse` TagComment " foo "

Predicate-based combinator

valueparseSatisfies :: Show a => Either String a -> (a -> Bool) -> Expectation

Source#

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

This can fail if the parsing doesn't succeed or if it succeeds but the value doesn't match the predicate.

">>>" ~> many (char '>')
  `parseSatisfies` ((==3) . length)

Inspecting the result

valueshouldSucceedOn :: (Source p s s' r, Show a) => p s' a -> s -> Expectation

Source#

Check that a parser succeeds on some given input

char 'x' `shouldSucceedOn` "x"

valueshouldFailOn :: (Source p s s' r, Show a) => p s' a -> s -> Expectation

Source#

Check that a parser fails on some given input

char 'x' `shouldFailOn` "a"

Inspecting unconsumed input

valueleavesUnconsumed

:: (Source p s s' r, Leftover r s)
=> r a
-> s
-> Expectation

Source#

Checking that the given parser succeeds and yields the given part of the input unconsumed. Intended to be used in conjunction with ~?>

("xa" :: Text) ~?> char 'x'
  `leavesUnconsumed` "a"

The Source class, connecting parsers and inputs

class

class (Eq string, Show string, IsString string) => Source (parser :: Type -> Type -> Type) string string' (result :: Type -> Type) | string -> parser, string -> result, string -> string' where

Source#

A class where each instance will just teach how to get an Either or the specific result type associated to the parser for the given input type.

Methods

(~>) :: string -> parser string' a -> Either String a
Feed some input to a parser and extract the result as either a failure String or an actually parsed value. Can be read as fed to.
```
-- "<a ...>" fed to an HTML parser 
"<a href=\"/foo\">Go to foo</a>" ~> htmlParser :: Either String a
```
(~?>) :: string -> parser string' a -> result a
Feed some input to a parser and extract it as the appropriate result type from that module.
This is not currently useful in the library per se, but is used in test-suites directly where we generally only deal with one concrete set of parser, input and result types. This lets us inspect the result in any way we want, e.g in conjunction with shouldSatisfy or a custom hspec combinator.

Instances4Source

Source Parser ByteString ByteString ResultDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source
Source Parser ByteString ByteString ResultDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source
Source Parser Text Text ResultDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source
Source Parser Text Text ResultDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source

The Leftover class, letting us inspect unconsumed input

classclass Leftover (r :: Type -> Type) s | r -> s where

Source#

Class for generically inspecting unconsumed input

Methods

leftover :: r a -> Maybe s
Get the unconsumed input from the result of a parser
Returns Nothing if the unconsumed input is ""

Instances4Leftover

Leftover Result ByteStringDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source
Leftover Result ByteStringDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source
Leftover Result TextDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source
Leftover Result TextDefined in hspec-attoparsec-0.1.0.2 · Test.Hspec.Attoparsec.Source