getByRole<E extends Element> method
- dynamic role, {
- bool exact = true,
- NormalizerFn normalizer([])?,
- dynamic name,
- bool? selected,
- bool? checked,
- bool? pressed,
- bool? expanded,
- bool queryFallbacks = false,
- int? level,
Returns a single element with the given role
value, defaulting to an exact
match.
Throws if no element is found. Use queryByRole
if a RTE is not expected.
You can also query the returned element(s) by their accessible name
by specifying the name
argument: getByRole(expectedRole, name: 'The name')
.
The accessible name
is for simple cases equal to the label of a form element, or the text content of a button,
or the value of the aria-label
attribute. It can be used to query a specific element if multiple elements
with the same role are present on the rendered content.
See: testing-library.com/docs/queries/byrole#api for more details and examples.
Use the logRoles utility to help determine what roles and names are visible to query for.
Related:
getAllByRole
Example
The example below demonstrates the usage of the
getByRole
query. However, the example is also relevant forgetAllByRole
,queryByRole
,queryAllByRole
,findByRole
andfindAllByRole
.Read more about the different types of queries to gain more clarity on which one suits your use-cases best.
<button onClick="...">Ok</button>
<button onClick="...">Cancel</button>
import 'package:react/react.dart' as react;
import 'package:react_testing_library/matchers.dart' show isInTheDocument;
import 'package:react_testing_library/react_testing_library.dart' as rtl;
import 'package:test/test.dart';
main() {
test('', () {
// Render the DOM shown in the example snippet above
final view = rtl.render(react.div({},
react.button({'onClick': (_) { /*...*/ }}, 'Ok'),
react.button({'onClick': (_) { /*...*/ }}, 'Cancel'),
));
expect(view.getByRole('button', name: 'Ok'), isInTheDocument);
expect(view.getByRole('button', name: 'Cancel'), isInTheDocument);
});
}
NOTE:
render()
supports React vDom elements / custom components created using either the
react or over_react packages.
The examples shown here use the
react
package since thereact_testing_library
does not have a direct dependency onover_react
- but both libraries are fully supported.
Options
role
This argument can be set to a String
, RegExp
, or a Function
which returns true
for a match and false
for a mismatch.
See the JS TextMatch
docs for more details
and examples.
exact
Defaults to true
; matches full strings, case-sensitive. When false
, matches substrings and is
not case-sensitive. It has no effect on regex or function arguments. In most cases using a regex
instead of a string gives you more control over fuzzy matching and should be preferred over exact: false
.
normalizer
An optional function which overrides normalization behavior.
Before running any matching logic against text in the DOM, DOM Testing Library automatically normalizes that text. By default, normalization consists of trimming whitespace from the start and end of text, and collapsing multiple adjacent whitespace characters into a single space.
If you want to prevent that normalization, or provide alternative normalization
(e.g. to remove Unicode control characters), you can provide a normalizer
function.
This function will be given a string and is expected to return a normalized version of that string.
NOTE: Specifying a value for
normalizer
replaces the built-in normalization, but you can call getDefaultNormalizer to obtain a built-in normalizer, either to adjust that normalization or to call it from your own normalizer.
See the JS TextMatch
precision and
JS TextMatch
normalization docs
for more details and examples.
hidden
If you set hidden
to true, elements that are normally excluded from the accessibility tree are
considered for the query as well.
The default behavior follows www.w3.org/TR/wai-aria-1.2/#tree_exclusion with the exception of
role="none"
and role="presentation"
which are considered in the query in any case.
See: testing-library.com/docs/queries/byrole#hidden for more details and examples.
selected
You can filter the returned elements by their selected state by setting selected: true
or selected: false
.
To learn more about the selected state and which elements can have this state see
ARIA aria-selected
.
See: testing-library.com/docs/queries/byrole#selected for more details and examples.
checked
You can filter the returned elements by their checked state by setting checked: true
or checked: false
.
See: testing-library.com/docs/queries/byrole#checked for more details and examples.
pressed
Buttons can have a pressed state. You can filter the returned elements by their pressed state by
setting pressed: true
or pressed: false
.
To learn more about the pressed state see ARIA aria-pressed
.
See: testing-library.com/docs/queries/byrole#pressed for more details and examples.
expanded
You can filter the returned elements by their expanded state by setting expanded: true
or expanded: false
.
To learn more about the expanded state and which elements can have this state see
ARIA aria-expanded
.
See: testing-library.com/docs/queries/byrole#expanded for more details and examples.
queryFallbacks
By default, it's assumed that the first role of each element is supported,
so only the first role can be queried. If you need to query an element by
any of its fallback roles instead, you can use queryFallbacks: true
.
See: testing-library.com/docs/queries/byrole#queryfallbacks for more details and examples.
level
An element with the heading
role can be queried by any heading level getByRole('heading')
or by a specific heading level using the level
option getByRole('heading', level: 2)
.
The level option queries the element(s) with the heading
role matching the indicated level
determined by the semantic HTML heading elements <h1>
-<h6>
or matching the aria-level
attribute.
To learn more about the aria-level
property, see
ARIA aria-level
.
See: testing-library.com/docs/queries/byrole#level for more details and examples.
Implementation
E getByRole<E extends Element>(
/*TextMatch*/ dynamic role, {
bool exact = true,
NormalizerFn Function([NormalizerOptions?])? normalizer,
bool hidden = false,
/*TextMatch*/ dynamic name,
bool? selected,
bool? checked,
bool? pressed,
bool? expanded,
bool queryFallbacks = false,
int? level,
}) =>
withErrorInterop(
() => _jsGetByRole(
getContainerForScope(),
TextMatch.toJs(role),
buildByRoleOptions(
exact: exact,
normalizer: normalizer,
hidden: hidden,
name: name,
selected: selected,
checked: checked,
pressed: pressed,
expanded: expanded,
queryFallbacks: queryFallbacks,
level: level,
),
) as E,
);