[FYI] Change in default set of package directories to ignore: .pub -> .dart_tool/pub

[Kevin Moore]

If you care about what's in .gitignore files for Dart/Flutter projects – or if you create documents or tools that deal with such things, keep reading...

tl;dr: docs/templates that deal with .gitignore should start include .dart_tool 

Details:

• The pub tool often creates a '.pub' directory in a Dart package to cache snapshots for package binaries.
  
• We have other tools – like package:build – that also needs to cache artifacts.
  
• We've decided to standardize on `.dart_tool` as the place all tools should put their package-level caches
• Instead of inventing a new "dot" directory for every tool – and then having to educate folks to ignore it.
• Convention: .dart_tool/name_of_package
• pub will start using .dart_tool/pub soon
• Commit has already landed in the pub repo: https://github.com/dart-lang/pub/commit/68a6c12602d564316bc9aa0f115ad625d825effe
• Need to sync pub into the SDK for this to go live: https://github.com/dart-lang/sdk/issues/32030 
• build tools have used .dart_tool/build for a while now

We already document .dart_tool on our site: https://www.dartlang.org/guides/libraries/private-files

We've also updated stagehand templates: https://github.com/dart-lang/stagehand/commit/937a17da1c89c048a62b0b311ab1e1092fc0d40b

[Kevin Moore]

Just landed in the Dart SDK https://github.com/dart-lang/sdk/commit/699f7bc1b187557b55a285f7d950ea051de3c2d9

Plan on this in 2.0.0-dev.32+

[Kevin Moore]

Dart 2.0.0-dev.32 was just published with this change.

The pub client will delete the .pub directory for you.

Don't forget to update your .gitignore files!