Support sentinel-based ranges in default stringify

[seanmiddleditch]

Fix for issue #2003

• Enhances rangeToString to work with a separate iterator and sentinel type
• Adds a test to ensure this compiles

[horenmar]

Tests in default run cannot fail, or it will fail CI. Instead, you should use ::Catch::Detail::stringify in the test and check that the return value matches expected stringification.

[seanmiddleditch]

Ah, gotcha. Easy enough to fix, thanks.

[seanmiddleditch]

@horenmar - I'm not familiar with the approval test stuff here; should I be checking in the files that are modified locally on build?

[horenmar]

On a second look, this part seems to be missing from the documentation after the rewrite. 🤔

Approval tests diff known good output with current output. If there are changes, check that the diff makes sense, run scripts/approve.py and commit the updated baselines.

[codecov]

Codecov Report

Merging #2004 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2004   +/-   ##
=======================================
  Coverage   88.76%   88.76%           
=======================================
  Files         138      138           
  Lines        5648     5648           
=======================================
  Hits         5013     5013           
  Misses        635      635           

[horenmar]

Looks good now, thanks.