ropensci/drake: Improved visuals

Version 7.2.0

drake version 7.2.0 is being released early in order to ensure compatibility with development testthat, re https://github.com/ropensci/drake/issues/849.

• In the DSL (e.g. drake_plan(x = target(..., transform = map(...))) avoid inserting extra dots in target names when the grouping variables are character vectors (#847). Target names come out much nicer this way, but those name changes will invalidate some targets (i.e. they need to be rebuilt with make()).

• Use config$jobs_preprocess (local jobs) in several places where drake was incorrectly using config$jobs (meant for targets).
• Allow loadd(x, deps = TRUE, config = your_config) to work even if x is not cached (#830). Required disabling tidyselect functionality when deps TRUE. There is a new note in the help file about this, and an informative console message prints out on loadd(deps = TRUE, tidyselect = TRUE). The default value of tidyselect is now !deps.
• Minor: avoid printing messages and warnings twice to the console (#829).
• Ensure compatibility with testthat >= 2.0.1.9000.

• In drake_plan() transformations, allow the user to refer to a target's own name using a special .id_chr symbol, which is treated like a character string.
• Add a transparency argument to drake_ggraph() and render_drake_ggraph() to disable transparency in the rendered graph. Useful for R installations without transparency support.

• Use a custom layout to improve node positions and aspect ratios of vis_drake_graph() and drake_ggraph() displays. Only activated in vis_drake_graph() when there are at least 10 nodes distributed in both the vertical and horizontal directions.
• Allow nodes to be dragged both vertically and horizontally in vis_drake_graph() and render_drake_graph().
• Prevent dots from showing up in target names when you supply grouping variables to transforms in drake_plan() (#847).
• Do not keep drake plans (drake_plan()) inside drake_config() objects. When other bottlenecks are removed, this will reduce the burden on memory (re #800).
• Do not retain the targets argument inside drake_config() objects. This is to reduce memory consumption.
• Deprecate the layout and direction arguments of vis_drake_graph() and render_drake_graph(). Direction is now always left to right and the layout is always Sugiyama.
• Write the cache log file in CSV format (now drake_cache.csv by default) to avoid issues with spaces (e.g. entry names with spaces in them, such as "file report.Rmd")`.