* Migrate to `unittest2`
why:
Global symbol overflow when running NIM 1.2 on Github ci suggests that
unit tests run sort of separately. The replacement library `unittest2`
provides that.
* Build ci dependencies
* Added `IntervalSet`, sets of non-adjacent intervals
Relocated from nimbus-eth1 snap sync development
* Fix local import directive
* Fix --styleCheck complaints
* Attempt to get around CI problem by varying items
details:
Vary all_tests exec list
Hide useless globalness of `noisy` constant in non-debugging mode
* Re-route KeyError exceptions as Defect for all except the `[]` function
why:
Access via key is verified, error is returned via Result[]
* Refactor lruFetch() item rotation
why:
Previously, the item was deleted and re-inserted in the table although
for rotation, only the queue links need to be updated.
* Delete some KeyError annotations
why:
Was overlooked earlier
* More KeyError fixes
* `Result` refresh
* add full support for `Result[T, void]` (aka `Opt[T]` aka `Option[T]`)
* expand tests
* add `flatten`, `filter` of `Option` fame
* add `tryError` that raises a regular exception when result holds a
value
* fix `$` to print `ok`/`err` in lower-case, like the functions that
created the result
* add `orErr` that collapses all errors to a single value of a
potentially different type - useful when translating errors between
layers
* `capture` should work with `CatchableError`
* remove `Defect`-dependent tests
* Update stew/results.nim
* avoid redundant error message when converting error to string
* avoid multiple evaluation in `valueOr`
* add `unsafeError` to match `unsafeGet`
* let `valueOr` evaluate a block
* add `errorOr` to mirror `valueOr`
Looking at generated assembly, it turns out the optimizer is not smart
enough to get rid of the loop - use `copyMem` instead.
At least the compiler is smart enough to constant-propagate runtime
endian direction, resolving the review comment.
Also clarify why a minimum length is enfored - it could perhaps be
revisited, but that would leave a slightly odd API.
the `array` overloads are actually unnecessary with an optimizing
compiler - as long as it can prove the length, any extra checks will go
away on their own
also add `initCopyFrom`
* document optimizations
This definition is more robust. The previously existing version was
producing compilation errors in certain generic contexts. static
"regular" params are recommended in general as they are more flexible
than the explicit generic parameters.