cbindlist, mergelist

[jangorecki]

• cbindlist add function cbindlist #2576: very much like cbind() or data.table(), but better control over copies, retains key/index.
• mergelist [R-Forge #2461] Faster version of Reduce(merge, list(DT1,DT2,DT3,...)) called mergelist (a la rbindlist) #599: supports left, inner, full, right, semi, anti, cross joins and mult argument, implemented around bmerge:
  1. internal dtmerge calls bmerge and process its results to give indices ready to subset x and i tables. IMO dtmerge could be used to simplify [.data.table as well.
  2. internal mergepair calls dtmerge, gets indices, use them to expand or subset x and i, then it stacks them using cbindlist.
  3. exported mergelist loops around mergepair, avoids any copies inside, once joining finished, it then ensure that expected objects are copied.
• unfold C code for better codecov in C files that has been touched in this PR
• fix codecov gaps
• mult="error" [R-Forge #1654] Allow mult="error" #655: implemented inside bmerge
• allow.cartesian more precise allow.cartesian should be more precise #4383 (only for equi-joins!)
• rename allow.cartesian Rename allow.cartesian to allow.i.dups? #914

partially, because not hooked in [.data.table, this should go as a separate PR:

• cross join allow cross join in [.data.table #1717
• semi join Support x[!!y] anti-anti-join syntax  #915, Add syntax for "subsetting join" #2158

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extra testing vs SQLite db, for how="left|inner|full|right"

Rscript inst/tests/sqlite.Rraw.manual

[github-actions]

Generated via commit 5952dd8

Download link for the artifact containing the test results: ↓ atime-results.zip

Time taken to finish the standard R installation steps: 11 minutes and 17 seconds

Time taken to run atime::atime_pkg on the tests: 6 minutes and 9 seconds

[MichaelChirico]

@jangorecki I broke this down into digestible parts with Graphite's gt split --by-hunk. It took 60-90 minutes. It would have been faster (e.g. 30 minutes) if I (1) understood the structure of the PR more intimately --> could more easily decide how to split the hunks (2) use EDITOR=emacs (or vim), nano is not suitable for that kind of editing 🥲

[jangorecki]

Nice, I would be happy to do it myself but these days I am not able to volunteer my free time and there is no sponsor as in the past.