| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Test.Util.FS.Sim.Error
Description
HasFS instance wrapping SimFS that generates errors, suitable for
testing error handling.
Synopsis
- mkSimErrorHasFS ∷ ∀ m. (MonadSTM m, MonadThrow m) ⇒ StrictTVar m MockFS → StrictTVar m Errors → HasFS m HandleMock
- runSimErrorFS ∷ (MonadSTM m, MonadThrow m) ⇒ MockFS → Errors → (StrictTVar m Errors → HasFS m HandleMock → m a) → m (a, MockFS)
- withErrors ∷ MonadSTM m ⇒ StrictTVar m Errors → Errors → m a → m a
- type ErrorStream = Stream FsErrorType
- type ErrorStreamGetSome = Stream (Either FsErrorType Partial)
- type ErrorStreamPutSome = Stream (Either (FsErrorType, Maybe PutCorruption) Partial)
- newtype Stream a = Stream {}
- always ∷ a → Stream a
- mkStream ∷ [Maybe a] → Stream a
- mkStreamGen ∷ Int → Gen a → Gen (Stream a)
- null ∷ Stream a → Bool
- runStream ∷ Stream a → (Maybe a, Stream a)
- newtype Partial = Partial Word64
- hGetSomePartial ∷ Partial → Word64 → Word64
- hPutSomePartial ∷ Partial → ByteString → ByteString
- data PutCorruption
- corrupt ∷ ByteString → PutCorruption → ByteString
- data Errors = Errors {
- dumpStateE ∷ ErrorStream
- hOpenE ∷ ErrorStream
- hCloseE ∷ ErrorStream
- hSeekE ∷ ErrorStream
- hGetSomeE ∷ ErrorStreamGetSome
- hGetSomeAtE ∷ ErrorStreamGetSome
- hPutSomeE ∷ ErrorStreamPutSome
- hTruncateE ∷ ErrorStream
- hGetSizeE ∷ ErrorStream
- createDirectoryE ∷ ErrorStream
- createDirectoryIfMissingE ∷ ErrorStream
- listDirectoryE ∷ ErrorStream
- doesDirectoryExistE ∷ ErrorStream
- doesFileExistE ∷ ErrorStream
- removeFileE ∷ ErrorStream
- renameFileE ∷ ErrorStream
- allNull ∷ Errors → Bool
- genErrors ∷ Bool → Bool → Gen Errors
- simpleErrors ∷ ErrorStream → Errors
Simulate Errors monad
mkSimErrorHasFS ∷ ∀ m. (MonadSTM m, MonadThrow m) ⇒ StrictTVar m MockFS → StrictTVar m Errors → HasFS m HandleMock Source #
Introduce possibility of errors
TODO: Lenses would be nice for the setters
runSimErrorFS ∷ (MonadSTM m, MonadThrow m) ⇒ MockFS → Errors → (StrictTVar m Errors → HasFS m HandleMock → m a) → m (a, MockFS) Source #
withErrors ∷ MonadSTM m ⇒ StrictTVar m Errors → Errors → m a → m a Source #
Streams
type ErrorStream = Stream FsErrorType Source #
An ErrorStream is a possibly infinite Stream of (Maybe)
FsErrorType
Nothing indicates that there is no error.
Each time the ErrorStream is used (see runErrorStream), the first
element (Nothing in case the list is empty) is taken from the list and an
ErrorStream with the remainder of the list is returned. The first element
represents whether an error should be returned or not.
An FsError consists of a number of fields: fsErrorType, a
fsErrorPath, etc. Only the first fields is interesting. Therefore, we
only generate the FsErrorType. The FsErrorType will be used to
construct the actual FsError.
type ErrorStreamGetSome = Stream (Either FsErrorType Partial) Source #
ErrorStream for hGetSome: an error or a partial get.
type ErrorStreamPutSome = Stream (Either (FsErrorType, Maybe PutCorruption) Partial) Source #
ErrorStream for hPutSome: an error and possibly some corruption, or a
partial write.
mkStreamGen ∷ Int → Gen a → Gen (Stream a) Source #
Make a Stream generator based on a a generator.
The generator generates a finite stream of 10 elements, where each element
has a chance of being either Nothing or an element generated with the
given a generator (wrapped in a Just).
The first argument is the likelihood (as used by frequency) of a
Just where Nothing has likelihood 2.
Generating partial reads/writes
Given a Partial pp > 0, we do the following to make a call
to hGetSome or hPutSome partial:
hGetSome: we subtractpfrom the number of requested bytes. If that would result in 0 requested bytes or less, we request 1 byte. If the number of requested bytes was already 0, leave it untouched, as we can't simulate a partial read in this case.hPutSome: we drop the lastpbytes from the bytestring. If that would result in an empty bytestring, just take the first byte of the bytestring. If the bytestring was already empty, leave it untouched, as we can't simulate a partial write in this case.
Instances
Generating corruption for hPutSome
data PutCorruption Source #
Model possible corruptions that could happen to a hPutSome call.
Constructors
| SubstituteWithJunk Blob | The blob to write is substituted with corrupt junk |
| PartialWrite Partial | Only perform the write partially |
Instances
| Show PutCorruption Source # | |
Defined in Test.Util.FS.Sim.Error | |
| Arbitrary PutCorruption Source # | |
Defined in Test.Util.FS.Sim.Error | |
corrupt ∷ ByteString → PutCorruption → ByteString Source #
Apply the PutCorruption to the ByteString.
Error streams for HasFS
Error streams for the methods of the HasFS type class.
An ErrorStream is provided for each method of the HasFS type class.
This ErrorStream will be used to generate potential errors that will be
thrown by the corresponding method.
For hPutSome, an ErrorStreamWithCorruption is provided to simulate
corruption.
An Errors is used in conjunction with SimErrorFS, which is a layer on
top of SimFS that simulates methods throwing FsErrors.
Constructors
simpleErrors ∷ ErrorStream → Errors Source #
Use the given ErrorStream for each field/method. No corruption of
hPutSome.