jsbench 0.2.1

Dart->JS Size and Performance Tool

jsbench

A minimal Dart -> JavaScript size and performance tool.

This library assumes you are either using pub build or a similar tool to generate .dart.js files from .dart files, but otherwise makes no other assumptions. It is recommended to use --dump-info to output additional information about the compilation.

Example

The following is an example of running jsbench on this repository:

$ pub build
$ pub run jsbench

main.dart.js	35.9 kB
compiler overhead	16.6 kB	46.1%
minified?	Yes

noSuchMethod?	No
dart:_js_helper	10.9 kB	30.3%
dart:html	3.39 kB	09.4%
dart:core	2.47 kB	06.9%
dart:_interceptors	2.06 kB	05.7%

Usage

This tool should either be used via pub global activate or as part of your dev_dependencies.

Then, build your application, and run jsbench. For example:

$ pub build
$ pub run jsbench

To get more interesting information (not just disk size), add --dump-info:

transformers:
  - $dart2js:
      commandLineOptions:
          - --dump-info

See this packages' pubspec.yaml for an example.

If you want more information check out dump-info-visualizer.

Flags

--no-dump: Ignores all .info.json files on disk.

--no-collapse-package: Do not collapse all package:<name> libraries.

--dump-trivial-size: Threshold number of bytes to print out a library name.

--input: Glob pattern(s) to find emitted JavaScript files.

--exclude Glob pattern(s) to exclude when finding inputs.

--archive: Archive formats to recursively read from when finding inputs. Only tar is currently supported.