tree: 485cb8bce11810b78afeabf5aed9daa1e7efe0be [path history] [tgz]
  1. browsers/
  2. flutter/
  4. add_fields.dart
  6. aot_smoke_tests.dart
  7. apply_preapprovals.dart
  10. compare_results.dart
  11. dart2js_d8_hostchecked_tests.isolate
  13. dart_aot_test.dart
  15. dart_tests.isolate
  16. dart_tests_extended.isolate
  17. dartdoc_footer.html
  19. extend_results.dart
  20. find_base_commit.dart
  22. post_results_to_pubsub.dart
  26. results.dart
  28. test_matrix.json
  30. try_test.dart
  31. update_flakiness.dart


This folder contains scripts and configuration files used by Dart's continuous integration and testing infrastructure.

Test matrix

The file test_matrix.json defines the test configurations run by Dart's CI infrastructure. Changes to the test matrix affect all builds that include them.


The test matrix is a JSON document and consists of the "filesets" object and the "configurations" array.

The file sets define files and/or directories that need to be present for a test configuration at runtime. Any directory specified will be included along with its subdirectories recursively. Directory names must have a / at the end. All paths are relative to the SDK checkout's root directory.

"filesets": {
  "a_fileset_name": [
  "another_fileset_name": [

The builder configurations describe all test configurations a specific builder must execute. Each builder configuration is an object that specifies which builders it applies to, defines the build steps for the builders, and some additional metadata. Only one builder configuration can apply to a builder.

"configurations": [
    "builders": [
    "meta": {
      "description": "Description of this configuration."
    "steps": [

Each step is an object and must have a name. A step may also specify a script to run instead of the default script: tools/ Additional arguments may be specified. These arguments will be passed to the script.

"steps": [
    "name": "build it",
    "script": "tools/",
    "arguments": ["--a-flag", "target", "another_target"]
    "name": "test it",

A step using the default script may also be sharded across many machines using the "shards" parameter. If a step is sharded, it must specify a "fileset". Only the files and directories defined by the file set will be available to the script when it's running on a shard.

  "name": "shard the tests",
  "shards": 10,
  "fileset": "a_fileset_name"

Builder name parsing

The builder names are split by ‘-’ and each part is then examined if it is an option. Options can be runtimes (e.g. “chrome”), architectures (e.g. x64) and operating system families (e.g. win). For each valid option, additional arguments are passed to the tools/ and tools/ scripts.

Adding a new builder

To add a builder:

  1. Decide on a name.
  2. Add the builder name to a new or existing configuration.
  3. File an issue labelled “area-infrastructure” to get your builder activated.

Testing a new or modified builder

Builders can be tested using a tool called led that is included in depot_tools. Replace buildername and CL number with the correct values and run:

led get-builder<builder name> | \
led edit-cr-cl '<cl number>' | \
led launch

Adding a builder to the commit queue

For now, file an issue labeled “area-infrastructure” to get your builder added to the commit queue.



A builder has a name and defines the steps the need to be run when it is executed by a bot. In general, a builder defines how to build and test software.


A physical or virtual machine (or even a docker container) that executes all commands it receives. Often, these commands are the steps defined by a builder.


Sharded steps copy all files in a file set to as many bots as specified and runs the same command on all of the shards. Each shard has a shard number. The shard number and the total number of shards are passed as arguments to the command. The command is then responsible for running a subset of its work on each shard based on these arguments.