Solving extra blank line error #441

[deg4uss3r]

Hi guys taking a stab at #441

There are 3 tests that are failing:

• search_stream::tests::after_context_invert_one1
• search_stream::tests::before_context_invert_one1
• search_stream::tests::invert_match_line_numbers

This has to do with the way the tests are passed, since a command line test produces the correct assertion:

> ../target/debug/rg 'Sherlock' -v -C 1 ./sherlock 
1-For the Doctor Watsons of this world, as opposed to the Sherlock
2:Holmeses, success in the province of detective work must always
3-be, to a very large extent, the result of luck. Sherlock Holmes
4:can extract a clew from a wisp of straw or a flake of cigar ash;
5:but Doctor Watson has to have it taken out for him and dusted,
6:and exhibited clearly, with a label attached.

[BurntSushi]

Thanks for trying, I really appreciate it! Unfortunately, fixing this bug requires quite a bit more work. You need to know when you're at the end of the input, and you need to know it without impacting performance.

[BurntSushi]

Sorry, but this just won't work on multiple levels. Firstly, buf doesn't necessarily contain the entire contents of the file being searched (this is true for the memory map searcher only). Secondly, buf.lines().count() is recounting all of the lines in the buffer every time a match is written, which would be a devastating performance regression.

[BurntSushi]

Third, if the end user disabled line numbers, then this check won't run at all.