Struct proptest::strategy::Filter

pub struct Filter<S, F> { /* fields omitted */ }

Strategy and ValueTree filter adaptor.

See Strategy::prop_filter().

Trait Implementations

impl<S: Debug, F> Debug for Filter<S, F>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<S: Clone, F> Clone for Filter<S, F>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<S: Strategy, F: Fn(&<S::Value as ValueTree>::Value) -> bool> Strategy for Filter<S, F>

type Value = Filter<S::Value, F>

The value tree generated by this Strategy.

fn new_value(&self, runner: &mut TestRunner) -> Result<Self::Value, String>

Generate a new value tree from the given runner.

fn prop_map<O: Debug, F: Fn(<Self::Value as ValueTree>::Value) -> O>(
    self,
    fun: F
) -> Map<Self, F> where
    Self: Sized, 

Returns a strategy which produces values transformed by the function fun.

fn prop_flat_map<S: Strategy, F: Fn(<Self::Value as ValueTree>::Value) -> S>(
    self,
    fun: F
) -> Flatten<Map<Self, F>> where
    Self: Sized, 

Maps values produced by this strategy into new strategies and picks values from those strategies.

fn prop_ind_flat_map<S: Strategy, F: Fn(<Self::Value as ValueTree>::Value) -> S>(
    self,
    fun: F
) -> IndFlatten<Map<Self, F>> where
    Self: Sized, 

Maps values produced by this strategy into new strategies and picks values from those strategies while considering the new strategies to be independent.

fn prop_ind_flat_map2<S: Strategy, F: Fn(<Self::Value as ValueTree>::Value) -> S>(
    self,
    fun: F
) -> IndFlattenMap<Self, F> where
    Self: Sized, 

Similar to prop_ind_flat_map(), but produces 2-tuples with the input generated from self in slot 0 and the derived strategy in slot 1.

fn prop_filter<F: Fn(&<Self::Value as ValueTree>::Value) -> bool>(
    self,
    whence: String,
    fun: F
) -> Filter<Self, F> where
    Self: Sized, 

Returns a strategy which only produces values accepted by fun.

fn prop_union(self, other: Self) -> Union<Self> where
    Self: Sized, 

Returns a strategy which picks uniformly from self and other.

fn prop_recursive<F: Fn(Arc<BoxedStrategy<<Self::Value as ValueTree>::Value>>) -> BoxedStrategy<<Self::Value as ValueTree>::Value>>(
    self,
    depth: u32,
    desired_size: u32,
    expected_branch_size: u32,
    recurse: F
) -> Recursive<BoxedStrategy<<Self::Value as ValueTree>::Value>, F> where
    Self: Sized + 'static, 

Generate a recursive structure with self items as leaves.

fn boxed(self) -> BoxedStrategy<<Self::Value as ValueTree>::Value> where
    Self: Sized + 'static, 

Erases the type of this Strategy so it can be passed around as a simple trait object.

fn no_shrink(self) -> NoShrink<Self> where
    Self: Sized, 

Wraps this strategy to prevent values from being subject to shrinking.

impl<S: ValueTree, F: Fn(&S::Value) -> bool> ValueTree for Filter<S, F>

type Value = S::Value

The type of the value produced by this ValueTree.

fn current(&self) -> S::Value

Returns the current value.

fn simplify(&mut self) -> bool

Attempts to simplify the current value. Notionally, this sets the "high" value to the current value, and the current value to a "halfway point" between high and low, rounding towards low.

fn complicate(&mut self) -> bool

Attempts to partially undo the last simplification. Notionally, this sets the "low" value to one plus the current value, and the current value to a "halfway point" between high and the new low, rounding towards low.