main panics when following /dev/stdin since /dev/stdin is not seekable.
Check to see if file is seekable and use unbounded_seek if so.
Also `tail -f` with no files should not follow stdin.
Although for some tests this adds characters
we still use them there because the
brevity cost is now worth the benefit in
terms of instant, natural-language readability
and recognizability for people not familiar
with this tests of this module or even the project
FileMerger receives Lines Iterables of the pre-sorted input files
via push_file() It implements Iterator, which yields lines from the
input files in (merged) sorted order. If the input files are not sorted,
then the behavior is undefined.
Internally, FileMerger uses a
std::collections::BinaryHeap<MergeableFile>.
MergeableFile is an internal helper that implements Ord in a way that
BinaryHeap can use (note that we want smallest-first, but BinaryHeap
returns largest first, so MergeableFile::cmp() calls reverse() on
whatever compare_by() returns.
Made a new function sort_by(lines, compare_fns), which accepts a
list of compare_fns and calls lines.sort_by() with a closure that
calls each compare_fn in turn until one returns something other
than equal.
Default behavior ensures that String::cmp is the last element in the
compare_fns list (referred to as 'last resort' sorting by man sort).
Passing --stable (-s) turns this behaviour off.
Test cases provided for `sort --month` and `sort --month --stable`.
Updates to individual integration tests
- use proposed conventional approach to beginning tests
- use new convenience functions for using fixtures
- use new names for TestScenario
Updates to integration test modules
- add proposed conventional module-level functions
Updates to test/common/util.rs
- rename TestSet, and its methods, for semantic clarity
- create convenience functions for use of fixtures
- delete convenience functions obsoleted by new conventions
