tree dd428696c7f198b793ff2997cd19f0abf2c9fc2c
parent 423c1503b18ce655b4b1ef08d1162ad404286959
author Jens Johansen <jensj@google.com> 1598952643 +0000
committer Jens Johansen <jensj@google.com> 1598952643 +0000

[parser] Make begin/end events always come in pairs

This CL:
* Changes the events so beginX and endX events always comes in pairs
  (though technically not right as some specific events can be beginX
  endY --- but in those cases it is at least documented and used in code
  that actually tests it).
  -> This entails adding some events and converting something from
    "beginX" to "handleX" instead.
* Adds a utility that can generate an AST of sorts directly from the
  parser via a listener using the begin/end matching (and knowing of the
  specific ones that doesn't match directly).
* Adds a test that checks that - at least for all tested (50,000+) files
  - the AST actually generate "correctly", i.e. matches up begin/ends
  and ends up with a single top entry "CompilationUnit".
* Adds a different visualization to the parser listener events by
  displaying the "AST directly from the parser" in a UI that can be
  navigated. The visualization may not be the best, but it's certainly
  a stepping stone.

Change-Id: I9b27f7bbf3be442adc92f357c7b3c46da6f84cf7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/159664
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>