Struct proptest::test_runner::TestRng [−][src]
Proptest's random number generator.
Implementations
impl TestRng[src]
pub fn from_seed(algorithm: RngAlgorithm, seed: &[u8]) -> Self[src]
Create a new RNG with the given algorithm and seed.
Any RNG created with the same algorithm-seed pair will produce the same sequence of values on all systems and all supporting versions of proptest.
Panics
Panics if seed is not an appropriate length for algorithm.
pub fn bytes_used(&self) -> Vec<u8>[src]
Dumps the bytes obtained from the RNG so far (only works if the RNG is
set to Recorder).
Panics
Panics if this RNG does not capture generated data.
pub fn deterministic_rng(algorithm: RngAlgorithm) -> Self[src]
Returns a TestRng with a particular hard-coded seed.
The seed value will always be the same for a particular version of Proptest and algorithm, but may change across releases.
This is useful for testing things like strategy implementations without
risking getting "unlucky" RNGs which deviate from average behaviour
enough to cause spurious failures. For example, a strategy for bool
which is supposed to produce true 50% of the time might have a test
which checks that the distribution is "close enough" to 50%. If every
test run starts with a different RNG, occasionally there will be
spurious test failures when the RNG happens to produce a very skewed
distribution. Using this or TestRunner::deterministic() avoids such
issues.
Trait Implementations
impl Clone for TestRng[src]
fn clone(&self) -> TestRng[src]
pub fn clone_from(&mut self, source: &Self)1.0.0[src]
impl Debug for TestRng[src]
impl RngCore for TestRng[src]
fn next_u32(&mut self) -> u32[src]
fn next_u64(&mut self) -> u64[src]
fn fill_bytes(&mut self, dest: &mut [u8])[src]
fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>[src]
Auto Trait Implementations
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized, [src]
T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized, [src]
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized, [src]
T: ?Sized,
pub fn borrow_mut(&mut self) -> &mut T[src]
impl<T> From<T> for T[src]
impl<T, U> Into<U> for T where
U: From<T>, [src]
U: From<T>,
impl<R> Rng for R where
R: RngCore + ?Sized, [src]
R: RngCore + ?Sized,
pub fn gen<T>(&mut self) -> T where
Standard: Distribution<T>, [src]
Standard: Distribution<T>,
pub fn gen_range<T, R>(&mut self, range: R) -> T where
T: SampleUniform,
R: SampleRange<T>, [src]
T: SampleUniform,
R: SampleRange<T>,
pub fn sample<T, D>(&mut self, distr: D) -> T where
D: Distribution<T>, [src]
D: Distribution<T>,
pub fn sample_iter<T, D>(self, distr: D) -> DistIter<D, Self, T> where
D: Distribution<T>, [src]
D: Distribution<T>,
pub fn fill<T>(&mut self, dest: &mut T) where
T: Fill + ?Sized, [src]
T: Fill + ?Sized,
pub fn try_fill<T>(&mut self, dest: &mut T) -> Result<(), Error> where
T: Fill + ?Sized, [src]
T: Fill + ?Sized,
pub fn gen_bool(&mut self, p: f64) -> bool[src]
pub fn gen_ratio(&mut self, numerator: u32, denominator: u32) -> bool[src]
impl<T> ToOwned for T where
T: Clone, [src]
T: Clone,
type Owned = T
The resulting type after obtaining ownership.
pub fn to_owned(&self) -> T[src]
pub fn clone_into(&self, target: &mut T)[src]
impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src]
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
V: MultiLane<T>,