| name | generate-snapshot-tests |
| description | Generate snapshot test files for Sentry frontend React components. Use when asked to "generate snapshot tests", "add snapshot tests", "create visual snapshots", "write snapshot tests", "add visual regression tests", or "snapshot this component". Accepts an optional component path or name via $ARGUMENTS. |
| type | workflow-process |
Generate Snapshot Tests
Generate a *.snapshots.tsx file colocated with a Sentry React component, following the established pattern used by core design system components.
Step 1: Locate the Component
If $ARGUMENTS is provided, treat it as a path or component name. Otherwise ask the user which component to snapshot.
Search strategies:
static/app/components/core/<name>/<name>.tsx
static/app/components/core/<name>/index.tsx
static/app/components/<name>.tsx
static/app/components/<name>/index.tsx
Use Glob or Grep to find the file if the exact path is unknown.
Read the component source file to understand:
- The component's name and its exported
Props / <ComponentName>Props type
- Union types and enum-like string literals on props (e.g.,
variant, priority, size)
- Boolean toggle props (e.g.,
disabled, checked, busy)
- Whether the component is interactive (needs
onChange={() => {}} or similar no-op handlers)
Step 2: Determine the Import Path
| Condition | Import style |
|---|
Component lives under static/app/components/core/ AND is published as @sentry/scraps/<name> | import {ComponentName, type ComponentNameProps} from '@sentry/scraps/<name>'; |
Component lives under static/app/components/core/ but is NOT in @sentry/scraps | // eslint-disable-next-line @sentry/scraps/no-core-import -- SSR snapshot needs direct import to avoid barrel re-exports with heavy deps
import {ComponentName, type ComponentNameProps} from 'sentry/components/core/<path>'; |
| All other components | import {ComponentName, type ComponentNameProps} from 'sentry/components/<path>'; |
To check if a component is in @sentry/scraps, look for an existing import using @sentry/scraps/<name> in neighboring files, or check if other snapshot files in the same directory use @sentry/scraps.
Step 3: Identify Props to Snapshot
Read the TypeScript props and classify them:
| Prop type | Action |
|---|
Union of string literals ('sm' | 'md' | 'lg') | Snapshot each value with it.snapshot.each |
Boolean toggle with visual impact (disabled, checked) | Snapshot true and false states |
| Boolean flag with no visual test value | Skip or add a single named snapshot |
children / className / style / event handlers | Skip — not visually interesting on their own |
Prioritize props that change the component's visual appearance substantially. For interactive components (inputs, toggles), always include disabled/checked states.
Step 4: Write the Snapshot File
Name the output file <component-name>.snapshots.tsx, colocated with the component source file.
Required imports (always include)
import {ThemeProvider} from '@emotion/react';
import {ComponentName, type ComponentNameProps} from '@sentry/scraps/<name>';
import {darkTheme, lightTheme} from 'sentry/utils/theme/theme';
const themes = {light: lightTheme, dark: darkTheme};
Core structure
Always wrap in light/dark theme loop:
describe('ComponentName', () => {
describe.each(['light', 'dark'] as const)('%s', themeName => {
});
});
it.snapshot.each — for union prop variants
Use when iterating over multiple values of a single prop:
it.snapshot.each<ComponentProps['variant']>(['info', 'warning', 'success', 'danger'])(
'%s',
variant => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Component variant={variant}>Label</Component>
</div>
</ThemeProvider>
),
variant => ({theme: themeName, variant: String(variant)})
);
The third argument to it.snapshot.each is the metadata function — include all props that vary in the snapshot. This metadata is used for snapshot naming and diffing.
it.snapshot — for single named snapshots
Use for one-off states (disabled, checked combinations, etc.):
it.snapshot('disabled-unchecked', () => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Component disabled onChange={() => {}} />
</div>
</ThemeProvider>
));
Pass metadata as a third argument when it adds useful snapshot context:
it.snapshot(
'bold',
() => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Component bold>Bold text</Component>
</div>
</ThemeProvider>
),
{theme: themeName}
);
Sizing the container
Match container sizing to what makes the component readable:
| Situation | Wrapper |
|---|
| Default | <div style={{padding: 8}}> |
| Width-sensitive (alerts, text) | <div style={{padding: 8, width: 400}}> |
| Narrow (icons, small controls) | <div style={{padding: 8}}> |
Interactive components
For components that require event handlers (inputs, checkboxes, radios, switches), pass no-op handlers to satisfy required props:
<Component onChange={() => {}} />
<Component checked onChange={() => {}} />
Step 5: Ordering snapshots within the theme loop
Order cases from most impactful to least:
- Primary variant/priority prop (the most visible visual differentiator)
- Secondary variant props
- Size variants
- State combinations (disabled+unchecked, disabled+checked)
- Boolean modifiers (bold, italic, etc.)
- Edge cases and combined props
Examples
Simple variant component (Button-style)
import {ThemeProvider} from '@emotion/react';
import {Button, type ButtonProps} from '@sentry/scraps/button';
import {darkTheme, lightTheme} from 'sentry/utils/theme/theme';
const themes = {light: lightTheme, dark: darkTheme};
describe('Button', () => {
describe.each(['light', 'dark'] as const)('%s', themeName => {
it.snapshot.each<ButtonProps['priority']>([
'default',
'primary',
'danger',
'warning',
'link',
'transparent',
])(
'%s',
priority => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Button priority={priority}>{priority}</Button>
</div>
</ThemeProvider>
),
priority => ({theme: themeName, priority: String(priority)})
);
});
});
Interactive component with state combinations (Switch-style)
import {ThemeProvider} from '@emotion/react';
import {Switch, type SwitchProps} from '@sentry/scraps/switch';
import {darkTheme, lightTheme} from 'sentry/utils/theme/theme';
const themes = {light: lightTheme, dark: darkTheme};
describe('Switch', () => {
describe.each(['light', 'dark'] as const)('theme-%s', themeName => {
it.snapshot.each<SwitchProps['size']>(['sm', 'lg'])('size-%s-unchecked', size => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Switch size={size} onChange={() => {}} />
</div>
</ThemeProvider>
));
it.snapshot.each<SwitchProps['size']>(['sm', 'lg'])('size-%s-checked', size => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Switch checked size={size} onChange={() => {}} />
</div>
</ThemeProvider>
));
it.snapshot('disabled-unchecked', () => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Switch disabled onChange={() => {}} />
</div>
</ThemeProvider>
));
it.snapshot('disabled-checked', () => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8}}>
<Switch checked disabled onChange={() => {}} />
</div>
</ThemeProvider>
));
});
});
Component with multiple independent variant props (Alert-style)
When a component has multiple meaningful boolean or variant props that combine independently, add separate it.snapshot.each blocks per combination:
describe('Alert', () => {
describe.each(['light', 'dark'] as const)('%s', themeName => {
it.snapshot.each<AlertProps['variant']>([
'info',
'warning',
'success',
'danger',
'muted',
])(
'%s',
variant => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8, width: 400}}>
<Alert variant={variant}>This is a {variant} alert</Alert>
</div>
</ThemeProvider>
),
variant => ({theme: themeName, variant: String(variant)})
);
it.snapshot.each<AlertProps['variant']>([
'info',
'warning',
'success',
'danger',
'muted',
])(
'%s-no-icon',
variant => (
<ThemeProvider theme={themes[themeName]}>
<div style={{padding: 8, width: 400}}>
<Alert variant={variant} showIcon={false}>
This is a {variant} alert without icon
</Alert>
</div>
</ThemeProvider>
),
variant => ({theme: themeName, variant: String(variant), showIcon: 'false'})
);
});
});
Anti-Patterns
import {theme} from 'sentry/utils/theme';
import {darkTheme, lightTheme} from 'sentry/utils/theme/theme';
it.snapshot.each<Props['variant']>(['a', 'b'])('%s', variant => (
<Component variant={variant} />
));
it.snapshot.each<Props['variant']>(['a', 'b'])(
'%s',
variant => <Component variant={variant} />,
variant => ({theme: themeName, variant: String(variant)})
);
it.snapshot('custom-class', () => <Component className="foo" />);
import {Badge} from '@sentry/scraps/badge';
import {Badge} from 'sentry/components/core/badge/badge';
Checklist
Before finishing: