testament shouldn't be tied to nim repo's test suite when distributed as an external tool

[timotheecour]

testament was published as an external tool as an after thought; if it is to remain a valid tool for testing 3rd party code it should be stripped from logic that's specific to nim's own test suite.

Here are just 2 examples:

Example 1

# tests/flags/tmain.nim:
doAssert true

testament all

Current Output

Error: unhandled exception: cannot open: tests/flags/tgenscript.nim [IOError]

Expected Output

should not reference tests/flags/tgenscript.nim, which is a file specific to nim repo

Example 2

testament all calls these:
progress[all]: 1/6 starting: cat: debugger
progress[all]: 2/6 starting: cat: examples
progress[all]: 3/6 starting: cat: lib
progress[all]: 4/6 starting: cat: ic
progress[all]: 5/6 starting: cat: megatest
apart from megatest, the other categories don't make sense for testament as external tool

Possible Solution

separate out all logic specific to nim repo so it doesn't affect the testament tool that's distributed as a binary for 3rd party repos

Additional Information

• 1.5.1 25745ad
• root cause behind testament regression #16829

[Araq]

Totally agree, but the fix can be as simple as a bunch of if statements and a --nimsTestsuite flag. Or maybe see if tests is relative to ../bin which contains nim.exe.

[timotheecour]

see #16831