bsdgrep(1): Remove output separators between overlapping segments in context (-A/B/C) output

[kevans]

Summary

Make bsdgrep(1) more sensitive to context overlaps -- if it's printing context that either overlaps or is immediately adjacent to another bit of context, don't print a separator.

This combined with D10101 allows bsdgrep(1) to pass the remaining context tests in the Kyua tests.

Test Plan

Run kyua tests to make sure no additional regressions have occured.

[cem]

Do you have some before/after examples? Are these behaviors codified in tests?

[kevans]

In D10105#213548, @cem wrote:

Do you have some before/after examples? Are these behaviors codified in tests?

I do not have specific examples off hand, but this is codified in both the context and context2 tests. context2 requires both this and the -z flag to actually pass, though. I can whip up examples later tonight if requested.

[cem]

I'm a fan of Cram for testing this kind of CLI program output, but I don't suppose we have that, even in ports.

[cem]

In D10105#213549, @kevans91_ksu.edu wrote:

I do not have specific examples off hand, but this is codified in both the context and context2 tests. context2 requires both this and the -z flag to actually pass, though. I can whip up examples later tonight if requested.

Yes, please :-).

It would be good to have tests for all of the new behavior(s), too (if context/context2 don't cover it all).

[kevans]

In D10105#213551, @cem wrote:

Yes, please :-).

Alright, so, given this input file:

a
b
c
d
e
f

Current behavior:

$ egrep -C 1 'b|d' test_file
a
b
c
--
--
c
d
e
$ egrep -C 1 'b|e' test_file
a
b
c
--
--
d
e
f

New behavior:

$ egrep -C 1 'b|d' test_file
a
b
c
d
e
$ egrep -C 1 'b|e' test_file
a
b
c
--
d
e
f

Tthings to note:

• Non-overlapping segments no longer have two separators between them
• Overlapping segments no longer have separators between them with overlapping sections repeated -- I personally really appreciate this part, given that it's a slightly stronger assertion about the input file, making it more obvious that the context overlaps without -n

It would be good to have tests for all of the new behavior(s), too (if context/context2 don't cover it all).

context and context2 do indeed over all of this and D10101. D10108 grew test cases since you last accepted it for the new grep -r behavior from that review as well as rgrep matching the equivalent grep -r in behavior, so those four test cases total should cover all of the newer behaviors.