Dart Test Fundamentals

When to use this skill

Use this skill when:

Writing new test files.
structuring test suites with
```
group
```
.
Configuring test execution via
```
dart_test.yaml
```
.
Understanding test lifecycle methods.

Core Concepts

1. Test Structure (

test

and

group

)

test
: The fundamental unit of testing.

dart

test('description', () {
  // assertions
});

group
: Used to organize tests into logical blocks.
- Groups can be nested.
- Descriptions are concatenated (e.g., "Group Description Test Description").
- Helps scope
```
setUp
```
  and
```
tearDown
```
  calls.
- Naming: Use
```
PascalCase
```
  for groups that correspond to a class name (e.g.,
```
group('MyClient', ...)
```
  ).
- Avoid Single Groups: Do not wrap all tests in a file with a single
```
group
```
  call if it's the only one.
Naming Tests:
- Avoid redundant "test" prefixes.
- Include the expected behavior or outcome in the description (e.g.,
```
'throws StateError'
```
  or
```
'adds API key to URL'
```
  ).
- Descriptions should read well when concatenated with their group name.
Named Parameters Placement:
- For
```
test
```
  and
```
group
```
  calls, place named parameters (e.g.,
```
testOn
```
  ,
```
timeout
```
  ,
```
skip
```
  ) immediately after the description string, before the callback closure. This improves readability by keeping the test logic last.
  dart
```
test('description', testOn: 'vm', () {
  // assertions
});
```

2. Lifecycle Methods (

setUp

tearDown

)

setUp
: Runs before every
```
test
```
in the current
```
group
```
(and nested groups).
tearDown
: Runs after every
```
test
```
in the current
```
group
```
.
setUpAll
: Runs once before any test in the group.
tearDownAll
: Runs once after all tests in the group.

Best Practice:

Use
```
setUp
```
for resetting state to ensure test isolation.
Avoid sharing mutable state between tests without resetting it.

3. Configuration (

dart_test.yaml

)

The

dart_test.yaml

file configures the test runner. Common configurations include:

Platforms

Define where tests run (vm, chrome, node).

yaml

platforms:
  - vm
  - chrome

Timeouts

Set default timeouts for tests.

yaml

timeouts:
  2x # Double the default timeout

4. File Naming

Test files must end in
```
_test.dart
```
to be picked up by the test runner.
Place tests in the
```
test/
```
directory.

Common commands

```
dart test
```
: Run all tests.
```
dart test test/path/to/file_test.dart
```
: Run a specific file.
```
dart test --name "substring"
```
: Run tests matching a description.

Related Skills

dart-test-fundamentals

is the core skill for structuring and configuring tests. For writing assertions within those tests, refer to:

dart-matcher-best-practices
: Use this if the project sticks with the traditional
```
package:matcher
```
(
```
expect
```
calls).
dart-checks-migration
: Use this if the project is migrating to the modern
```
package:checks
```
(
```
check
```
calls).

dart-test-fundamentals

NPX Install

Tags

SKILL.md Content

Dart Test Fundamentals

When to use this skill

Core Concepts

1. Test Structure (
`test`
and
`group`
)

2. Lifecycle Methods (
`setUp`
,
`tearDown`
)

3. Configuration (
`dart_test.yaml`
)

Platforms

Tags

Timeouts

4. File Naming

Common commands

Related Skills

dart-test-fundamentals

NPX Install

Tags

SKILL.md Content

Dart Test Fundamentals

When to use this skill

Core Concepts

1. Test Structure (test and group)

2. Lifecycle Methods (setUp, tearDown)

3. Configuration (dart_test.yaml)

Platforms

Tags

Timeouts

4. File Naming

Common commands

Related Skills

1. Test Structure (
`test`
and
`group`
)

2. Lifecycle Methods (
`setUp`
,
`tearDown`
)

3. Configuration (
`dart_test.yaml`
)