Bug#924786: ITP: golang-github-michaeltjones-walk -- Fast parallel version of golang filepath.Walk()

["Dawid Dziurla" <dawidd0811@gmail.com>]

Package: wnpp
Severity: wishlist
Owner: Dawid Dziurla <dawidd0811@gmail.com>

* Package name    : golang-github-michaeltjones-walk
  Version         : 0.0~git20161122.4748e29-1
  Upstream Author : Michael T Jones
* URL             : https://github.com/MichaelTJones/walk
* License         : Expat
  Programming Lang: Go
  Description     : Fast parallel version of golang filepath.Walk()

 Performs traversals in parallel so set GOMAXPROCS appropriately. Vaues
 of 8 to 16 seem to work best on my 4-CPU plus 4 SMT pseudo-CPU
 MacBookPro. The result is about 4x-6x the traversal rate of the standard
 Walk().  The two are not identical since we are walking the file system
 in a tumult of asynchronous walkFunc calls by a number of goroutines. So,
 take note of the following:
 • This walk honors all of the walkFunc
 error semantics but as multiple user-supplied walkFuncs may simultaneously
 encounter a traversal error or generate one to stop traversal, only the
 FIRST of these will be returned as the Walk() result.
 • Further, since
 there may be a few files in flight at the instant of  error discovery, a
 few more walkFunc calls may happen after the first error-generating call
 has signaled its desire to stop. In general this is a non-issue but it
 could matter so pay attention when designing your walkFunc. (For example,
 if you accumulate results then you need to have your own means to know
 to stop accumulating once you signal an error.)
 • Because the walkFunc
 is called concurrently in multiple goroutines, it needs to be careful
 about what it does with external data to avoid collisions. Results may
 be printed using fmt, but generally the best plan is to send results
 over a channel or accumulate counts using a locked mutex.
 .
 These issues
 are illustrated/handled in the simple traversal programs supplied with
 walk. There is also a test file that is just the tests from filepath
 in the Go language's standard library. Walk passes these tests when
 run in single process mode, and passes most of them in concurrent mode
 (GOMAXPROCS > 1). The problem is not a real problem, but one of the
 test expecting a specific number of errors to be found based on presumed
 sequential traversals.

This package is in the dependency tree of Lazygit (#908894)