Reference

Test UI is a browser interface for reviewing completed acton test runs with traces, transaction trees, logs, source links, coverage data when the run includes --coverage, and gas profiles when the run includes --gas-profile.

1. Start Test UI

# Run tests and open Test UI in browser
acton test --ui

Useful options:

# Custom UI port
acton test --ui --ui-port 23456

# Run only selected tests in UI
acton test tests/counter.test.tolk --ui --filter "test deploy"

# Open Test UI with coverage viewer enabled
acton test --coverage --ui

# Open Test UI with gas profile flamegraphs enabled
acton test --gas-profile build/gas.cpuprofile --ui

Test UI overview with test list sidebar, summary cards, and details pane

If --ui-port is already in use, Test UI server cannot start. Choose another free port, for example --ui-port 23456.

The Coverage tab is available only when the test run is started with both --coverage and --ui.

The Profile tab is available only when the test run is started with both --gas-profile <FILE> and --ui. Add --gas-profile-include-tests when the expensive work happens inside .test.tolk unit-test get methods.

Test search and status filters

Text filter (Filter tests...) matches test names
Status toggles for all statuses: Passed, Failed, Skipped, Todo

Both can be used simultaneously.

Tests are grouped by files
Each suite can be collapsed/expanded
Suite row shows number of visible tests
Suite status icon highlights failed suites
Clicking a test opens full details on the right

Sidebar filters with text search and status toggles

Theme toggle (light/dark)
Collapse sidebar button

Sidebar controls with theme toggle and collapse button

3. Test header and IDE integration

The selected test header contains:

test status icon
suite and test names
quick-open button for current IDE
IDE selector dropdown

Supported IDE deep links include Cursor, VS Code-family, and JetBrains IDEs.

Keyboard shortcuts

. opens current test location in selected IDE
Esc closes IDE dropdowns

IDE selector dropdown in test header with quick-open action

4. Info tab

The Info tab includes:

test status
suite name
file location (file:line:column)
duration and total transaction count

Failure diagnostics

For failed tests, Info tab also shows:

error message block
detailed matcher/exit-code message
structured mismatch context for transaction assertions (from, to, and matcher params)
failed transaction tree (if available)
highlighted source snippet around failure location

Failed test details with error block, mismatch context, and highlighted source snippet

Fee summary

If traces are available, Info tab also shows Fee Summary table per trace:

trace name
transaction count
gas used
total fee

Clicking a trace row opens that trace in Transactions tab.

For baseline and regression-oriented fee analysis, see the gas profiling and snapshots page.

Name trace chains in tests with txs.giveName(...) to make trace tabs and fee summaries easier to read.

Fee Summary table with per-trace gas, forward fee, and total fee columns

5. Transactions tab

If a test has trace data, Transactions tab provides full tree visualization.

Trace switcher

When a test has multiple traces, tabs appear above content
Selecting a trace updates tree and details

Transaction tree

Horizontal transaction tree with root blockchain node
Node color indicates success/failure
Dashed edges indicate bounced messages
Hover tooltip shows route, state transition, and gas/exit-code details

Transaction details panel

Clicking a node opens detailed transaction view below tree:

message route (from -> to) and message metadata
opcode info with ABI name (when available)
fee breakdown and compute/action phase status
exit code details and quick copy controls

Transactions tab with trace tree and selected transaction details

Actions details

When action phase has out actions:

action cards are shown (sendMsg, reserve, setCode)
failed actions are marked with Failed badge
expanded action details include destination, payload, mode decoding, and failure reason

Actions panel showing out actions and expanded action details

6. Logs tab

Logs tab shows Executor Log and VM Log grouped by transaction for the selected trace. If a transaction has no logs, it is skipped; if all VM logs are missing for the selected trace, UI shows a hint to rerun with acton test --ui --verbose.

Logs tab with Executor Log and VM Log grouped by transaction

7. Profile tab

When the run includes acton test --gas-profile build/gas.cpuprofile --ui, Test UI adds a dedicated Profile tab with:

contract tabs for profiled contracts
gas-weighted flamegraph for the selected contract
selected frame details: source location, total gas, self gas, and contract share

The global profile view is grouped by contract. Function names inside each contract do not repeat the contract prefix, so frames such as Elector:onInternalMessage are shown as onInternalMessage inside the Elector contract tab.

When the run also includes --gas-profile-include-tests, individual tests with recorded unit execution get a Profile tab next to Info, Transactions, and Logs. The per-test profile hides Acton runtime frames from @acton/.acton paths to keep user-code hot paths visible. The exported cpuprofile or collapsed file remains complete.

For command examples and snapshot comparison workflows, see the gas profiling and snapshots page.

8. Coverage tab

When the run includes acton test --coverage --ui, Test UI adds a dedicated Coverage tab with:

summary cards for overall coverage
file list sorted by coverage score
source viewer with annotated covered and uncovered lines
search field for filtering files

The Coverage tab supports a quick visual scan of uncovered lines without leaving the browser UI.