tasty- Modern and extensible testing framework

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Extensible options. They are used for provider-specific settings, ingredient-specific settings and core settings (such as the test name pattern).


IsOption class

class Typeable v => IsOption v where Source #

An option is a data type that inhabits the IsOption type class.

Minimal complete definition

defaultValue, parseValue, optionName, optionHelp


defaultValue :: v Source #

The value to use if the option was not supplied explicitly

parseValue :: String -> Maybe v Source #

Try to parse an option value from a string. Consider using safeReadBool for boolean options and safeRead for numeric options.

optionName :: Tagged v String Source #

The option name. It is used to form the command line option name, for instance. Therefore, it had better not contain spaces or other fancy characters. It is recommended to use dashes instead of spaces.

optionHelp :: Tagged v String Source #

The option description or help string. This can be an arbitrary string.

optionCLParser :: Parser v Source #

A command-line option parser.

It has a default implementation in terms of the other methods. You may want to override it in some cases (e.g. add a short flag) and flagCLParser, mkFlagCLParser and mkOptionCLParser might come in handy.

Even if you override this, you still should implement all the methods above, to allow alternative interfaces.

Do not supply a default value here for this parser! This is because if no value was provided on the command line we may lookup the option e.g. in the environment. But if the parser always succeeds, we have no way to tell whether the user really provided the option on the command line.


IsOption TestPattern Source # 
IsOption Timeout Source # 
IsOption NumThreads Source # 
IsOption ListTests Source # 
IsOption UseColor Source #

Control color output

IsOption HideSuccesses Source # 
IsOption Quiet Source # 

Option sets and operations

data OptionSet Source #

A set of options. Only one option of each type can be kept.

If some option has not been explicitly set, the default value is used.

setOption :: IsOption v => v -> OptionSet -> OptionSet Source #

Set the option value

changeOption :: forall v. IsOption v => (v -> v) -> OptionSet -> OptionSet Source #

Change the option value

lookupOption :: forall v. IsOption v => OptionSet -> v Source #

Query the option value

singleOption :: IsOption v => v -> OptionSet Source #

Create a singleton OptionSet

data OptionDescription where Source #

The purpose of this data type is to capture the dictionary corresponding to a particular option.


Option :: IsOption v => Proxy v -> OptionDescription 


flagCLParser Source #


:: IsOption v 
=> Maybe Char

optional short flag

-> v

non-default value (when the flag is supplied)

-> Parser v 

Command-line parser to use with flags

mkFlagCLParser Source #


:: IsOption v 
=> Mod FlagFields v

option modifier

-> v

non-default value (when the flag is supplied)

-> Parser v 

Command-line flag parser that takes additional option modifiers.

mkOptionCLParser :: forall v. IsOption v => Mod OptionFields v -> Parser v Source #

Command-line option parser that takes additional option modifiers.

safeRead :: Read a => String -> Maybe a Source #

Safe read function. Defined here for convenience to use for parseValue.

safeReadBool :: String -> Maybe Bool Source #

Parse a Bool case-insensitively