Share of "active" repositories interacting with exactly one distinct person, per trailing window

The most direct available operationalisation of "coding alone": among repositories with any issue-based interaction in a trailing window (an "active" repo), what fraction have that activity concentrated in a single distinct author - core or non-core, no contrib_threshold applied - rather than spread across two or more people. Unlike author_density_tbl()'s per-repo-month rate, this is a repo-level, not-normalised-by-exposure share, deliberately: the question here isn't "how much less does each repo hear from outsiders" but "how many repositories, out of those that hear from anyone at all, hear from only one person" - a repo-count analogue of a shrinking bowling league's membership rolls, not of its per-lane activity rate.

Usage

solo_repo_share_tbl(
  issue_authors_tbl,
  repo_tbl,
  sources,
  window = 12L,
  months = NULL,
  date_start = as.Date("2015-01-01"),
  date_end = NULL
)

Arguments

issue_authors_tbl: As returned by fetch_issue_authors().
repo_tbl: As returned by build_repo_tbl().
sources: Character vector of source_name values to pool together (see issue_rate_tbl()). Repositories from every requested source are pooled into one combined share per month, not reported separately per source.
window: Trailing window, in months, over which a repository's distinct authors are counted before it's classed as solo/non-solo. Default 12, matching every other trailing-window metric in this package.
months: Optional Date vector (first-of-month) of specific months to compute the share for, instead of every month in date_start:date_end - useful for a cheap two-point (reference vs. latest) comparison without recomputing the full monthly series.
date_start, date_end: Date bounds for the default monthly sequence; ignored if months is supplied. date_end defaults to the start of the current month.

Value

A tibble: month, n_active_repos (repos with at least one distinct author in the trailing window), n_solo (of those, repos with exactly one), solo_share (n_solo / n_active_repos).

Examples

if (FALSE) { # \dontrun{
solo_tbl <- solo_repo_share_tbl (issue_authors_tbl, repo_tbl, c ("cran", "npm"))
} # }