Reduce cyclomatic complexity of try_merge_additional_files() (#292)

* Reduce cyclomatic complexity of try_merge_additional_files()

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

* Add NEWS entry for extracted helpers

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

* Fix formatting and unmatched-merge count in try_merge_one_file

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

* Simplify helpers and reduce try_merge_additional_files to complexity 12

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

* Address review: fix formatting, warn on ignored participant_key

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

* Distinguish warning messages for invalid participant_key, consistent := style

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

* Thread call param through resolve_longitudinal_key, use basename consistently

Co-authored-by: sbfnk <sebastian.funk@lshtm.ac.uk>

---------

Co-authored-by: sbfnk-bot <242615673+sbfnk-bot@users.noreply.github.com>

Author: sbfnk

NEWS.md

@@ -51,6 +51,13 @@
   data. The `wpp2017` package is now a suggested dependency rather than a
   required import (#258).
 
+* Reduced cyclomatic complexity of `try_merge_additional_files()` by extracting
+  helper functions (#289).
+
+* Fixed unmatched-merge warning count when merging files with duplicate keys;
+  previously, the count could be wrong (or negative) due to counting join pairs
+  rather than distinct matched rows (#289).
+
 * `get_survey()`, `download_survey()`, `list_surveys()`, `get_citation()`, and
   `survey_countries()` now warn unconditionally when called. These functions
   were soft-deprecated in 0.5.0 and users should switch to the

R/globals.R

@@ -88,7 +88,7 @@ utils::globalVariables(c(
   "title", # <.list_surveys>
   "creator", # <.list_surveys>
   "identifier.2", # <.list_surveys>
-  "..merge_id", # <try_merge_additional_files>
+  "..merge_id", # <try_merge_one_file>
   "..main_id", # <try_merge_additional_files>
   "..original.lower.age.limit", # <pop_age>
   "..segment", # <pop_age>