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entering-text

Testing & Quality
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Use this skill to drive Jetpack Compose text fields from tests with the text-specific actions — performTextInput (insert at cursor via the InsertTextAtCursor semantics action), performTextReplacement (clear + replace via SetText), performTextClearance (replace with empty string), performTextInputSelection (set TextRange selection), and performImeAction (fire the configured IME action such as Next, Done, Search). Covers the auto-focus path, the enabled / editable / focusable preconditions, the append vs replace gotcha that produces "helloworld" instead of "world", and the IME-action focus chain (Next advances focus to the next focusable). Use when the developer asks "how do I type into a TextField in a test", "test an IME Next button", "test a clear-text action", "BasicTextField won't accept input", "text input duplicated in test", or reports "Failed to perform text input" / "Failed to perform IME action" / "Default ImeAction" errors.

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Entering Text — performTextInput, performTextReplacement, performImeAction

Compose text fields expose semantics actions for IME-style edits. The test API wraps those actions so a single call types text, replaces text, clears text, sets a selection, or fires the IME action. Every entry point auto-focuses the node when needed and asserts that the node is enabled and editable, surfacing precise errors when one of those preconditions fails.

When to use this skill

  • The test types into TextField, OutlinedTextField, BasicTextField, or any composable that exposes the InsertTextAtCursor / SetText semantics actions.
  • The test fires an IME action — ImeAction.Next to advance focus, ImeAction.Done to dismiss the keyboard, ImeAction.Search / Send / Go to trigger a form submit.
  • The test must clear an existing value, or replace the full value with new text.
  • The test asserts cursor or selection state with performTextInputSelection(TextRange(...)).

When NOT to use this skill

  • The test sends an arbitrary key shortcut into a focused field (e.g. Ctrl+A, Tab, arrow keys). Use ../injecting-mouse-and-keyboard/SKILL.md.
  • The test only checks the displayed text without typing — assert via ../../assertions/asserting-node-state-and-text/SKILL.md.
  • A finder cannot locate the text field. Verify the matcher first via ../../finders/finding-nodes-by-tag-text-content/SKILL.md.
  • The test asserts state restoration of the typed text after rotation. See ../../setup/configuring-test-dependencies/SKILL.md and StateRestorationTester.

Prerequisites

  • androidx.compose.ui:ui-test-junit4 (or ui-test for runComposeUiTest) configured per ../../setup/configuring-test-dependencies/SKILL.md.
  • The TextField carries Modifier.testTag("…") from production code so the test selects it deterministically.
  • The field is enabled = true. performTextInput calls assert(isEnabled()) before doing anything (TextActions.kt:125).
  • For performImeAction: the field declares both ImeAction != ImeAction.Default (via KeyboardOptions(imeAction = …)) and an OnImeAction handler (via KeyboardActions(...) or default keyboard actions). The action assertion checks both (TextActions.kt:99-100).

Workflow

  1. Type text at the cursor — performTextInput(text) (TextActions.kt:37-41). Internally invokes SemanticsActions.InsertTextAtCursor with AnnotatedString(text). Auto-focuses the node first when it is not focused (getNodeAndFocus — TextActions.kt:119-138). Throws AssertionError("Failed to perform text input.") if the node is not enabled, not focusable, or does not advertise InsertTextAtCursor.
rule.onNodeWithTag(Tag).performTextInput("Hello ")
  1. Replace the entire text — performTextReplacement(text) (TextActions.kt:81-84). Invokes SemanticsActions.SetText, which clears existing text and inserts new text. Use this when the field already has a value the test wants to overwrite. MUST NOT be used to "type more characters" — see the WRONG/RIGHT pair below.
rule.onNodeWithTag(Tag).performTextReplacement("New value")
  1. Clear the text — performTextClearance() (TextActions.kt:28-30). Sugar for performTextReplacement(""). The field must be focusable + have SetText.
rule.onNodeWithTag(Tag).performTextClearance()
  1. Set the selection / cursor — performTextInputSelection(selection: TextRange, relativeToOriginalText: Boolean = true) (TextActions.kt:61-72). Maps to SemanticsActions.SetSelection. When relativeToOriginalText = true, indices refer to the original (untransformed) text; false makes them refer to the post-VisualTransformation text.
rule.onNodeWithTag(Tag).performTextInput("Hello World")
rule.onNodeWithTag(Tag).performTextInputSelection(TextRange(0, 5)) // selects "Hello"
  1. Fire the IME action — performImeAction() (TextActions.kt:97-117). Pre-conditions, in order:
    • assert(hasPerformImeAction()) — the field declares OnImeAction.
    • assert(!hasImeAction(ImeAction.Default)) — the action is something other than the default.
    • tryPerformAccessibilityChecks().
    • Auto-focus via getNodeAndFocus(requireEditable = false).
    • Invoke OnImeAction and require it returned true; otherwise throw AssertionError("Failed to perform IME action, handler returned false.").
rule.onNodeWithTag(InitialFieldTag).performImeAction()
  1. Pair with assertTextEquals to confirm the expected post-state. The merged-tree default applies to text assertions exactly as to finders — see ../../assertions/asserting-node-state-and-text/SKILL.md.

Patterns

Pattern: Append (performTextInput) vs replace (performTextReplacement)

The most common gotcha — the two APIs look interchangeable but compose differently.

// WRONG
rule.onNodeWithTag(Tag).performTextInput("hello")
rule.onNodeWithTag(Tag).performTextInput("world")
rule.onNodeWithTag(Tag).assertTextEquals("world")
// WRONG because: performTextInput maps to InsertTextAtCursor, not SetText. The cursor
// remains at the end of "hello" after the first call, so the second call inserts
// "world" there. Final value is "helloworld" — assertion fails.

// RIGHT
rule.onNodeWithTag(Tag).performTextInput("hello")
rule.onNodeWithTag(Tag).performTextReplacement("world")
rule.onNodeWithTag(Tag).assertTextEquals("world")

performTextReplacement calls SemanticsActions.SetText (TextActions.kt:83), which clears existing characters before inserting the new text — equivalent to the IME's "set composing region to whole text and replace" path. Use it any time the second call should overwrite, not append.

Pattern: Canonical insert + assert

From BasicTextFieldTest.kt:171-194:

@Test
fun textFieldState_textChange_updatesState() {
    val state = TextFieldState("Hello ", TextRange(Int.MAX_VALUE))
    inputMethodInterceptor.setTextFieldTestContent {
        BasicTextField(state = state, modifier = Modifier.fillMaxSize().testTag(Tag))
    }

    rule.onNodeWithTag(Tag).performTextInput("World!")

    rule.runOnIdle { assertThat(state.text.toString()).isEqualTo("Hello World!") }
}

@Test
fun textFieldState_textChange_updatesSemantics() {
    val state = TextFieldState("Hello ", TextRange(Int.MAX_VALUE))
    inputMethodInterceptor.setTextFieldTestContent {
        BasicTextField(state = state, modifier = Modifier.fillMaxSize().testTag(Tag))
    }

    rule.onNodeWithTag(Tag).performTextInput("World!")

    rule.onNodeWithTag(Tag).assertTextEquals("Hello World!")
}

The cursor is positioned at TextRange(Int.MAX_VALUE) (end of text) when constructing TextFieldState. performTextInput("World!") inserts at that cursor — final value "Hello World!". State reads happen inside runOnIdle (skydoves hot take #5).

Pattern: Replace then assert — BasicTextFieldTest.kt:442-466

@Test
fun textField_whenStateObjectChanges_restartsInput() {
    val state1 = TextFieldState("Hello")
    val state2 = TextFieldState("World")
    var toggleState by mutableStateOf(true)
    val state by derivedStateOf { if (toggleState) state1 else state2 }
    inputMethodInterceptor.setTextFieldTestContent {
        BasicTextField(
            state = state,
            enabled = true,
            modifier = Modifier.fillMaxSize().testTag(Tag),
        )
    }

    with(rule.onNodeWithTag(Tag)) {
        performTextReplacement("Compose")
        assertTextEquals("Compose")
    }
    toggleState = !toggleState
    with(rule.onNodeWithTag(Tag)) {
        performTextReplacement("Compose2")
        assertTextEquals("Compose2")
    }
    assertThat(state1.text.toString()).isEqualTo("Compose")
    assertThat(state2.text.toString()).isEqualTo("Compose2")
}

performTextReplacement overwrites whatever the field's current value happens to be — making it the right call when state is rotated underneath.

Pattern: Clearing then refilling

rule.onNodeWithTag(Tag).performTextClearance()
rule.onNodeWithTag(Tag).performTextInput("Different")
rule.onNodeWithTag(Tag).assertTextEquals("Different")

performTextClearance is sugar for performTextReplacement("") (TextActions.kt:28-30). After it runs, the cursor is at position 0, so a follow-up performTextInput simply inserts at the start.

Pattern: IME-action focus chain (Next advances focus)

From DefaultKeyboardActionsTest.kt:130-149:

// Show keyboard.
rule.onNodeWithTag(initialTextField).performClick()
inputMethodInterceptor.assertSessionActive()
keyboardController.show()

// Act.
rule.onNodeWithTag(initialTextField).performImeAction()

// Assert.
when (imeAction) {
    Next -> {
        // Focus moves to the next item.
        assertThat(focusState1).isFalse()
        assertThat(focusState2).isFalse()
        assertThat(focusState3).isTrue()
    }
    Previous -> {
        // Focus moves to the previous item.
        assertThat(focusState1).isTrue()
        assertThat(focusState2).isFalse()
        assertThat(focusState3).isFalse()
    }
    Done -> {
        // No change to focus state.
        assertThat(focusState1).isFalse()
        assertThat(focusState2).isTrue()
        assertThat(focusState3).isFalse()

        // Software keyboard is hidden.
        keyboardController.assertHidden()
    }
}

Production must declare a non-default ImeAction for performImeAction to be valid:

BasicTextField(
    state = state,
    keyboardOptions = KeyboardOptions(imeAction = ImeAction.Next),
    modifier = Modifier.testTag(InitialFieldTag),
)

performImeAction asserts !hasImeAction(ImeAction.Default) first (TextActions.kt:100). Forgetting the keyboardOptions parameter yields AssertionError("Failed to perform IME action.").

Pattern: Set selection before replacing a substring

rule.onNodeWithTag(Tag).performTextInput("Hello World")
rule.onNodeWithTag(Tag).performTextInputSelection(TextRange(6, 11)) // select "World"
rule.onNodeWithTag(Tag).performTextInput("Compose")              // selection replaced
rule.onNodeWithTag(Tag).assertTextEquals("Hello Compose")

SemanticsActions.SetSelection honours the same path the IME uses, so a follow-up InsertTextAtCursor replaces the active selection with the new text. Pass relativeToOriginalText = false if the field installs a VisualTransformation (e.g. password mask, currency formatter) and the indices were computed against the displayed string.

Pattern: Disabled or non-editable field — clear error

If the field is enabled = false or the matcher resolves to a Text instead of a TextField, performTextInput throws AssertionError("Failed to perform text input."). The chain is:

  1. tryPerformAccessibilityChecks().
  2. assert(isEnabled()).
  3. assert(hasRequestFocusAction()).
  4. assert(hasSetTextAction()) and assert(hasInsertTextAtCursorAction()) (TextActions.kt:127-129).

When the assertion fires, dump the semantics tree via ../../debug/printing-the-semantics-tree/SKILL.md to confirm the matcher is not selecting a static Text.

Mandatory rules

  • MUST use performTextReplacement to overwrite an existing value. MUST NOT chain two performTextInput calls expecting the second to replace the first — they concatenate at the cursor.
  • MUST declare a non-default ImeAction (e.g. KeyboardOptions(imeAction = ImeAction.Next)) before calling performImeAction. The API asserts !hasImeAction(ImeAction.Default) (TextActions.kt:100) and throws otherwise.
  • MUST select the field by Modifier.testTag(...) whose value is a constant in production code — skydoves hot take #1.
  • MUST route post-input state assertions through rule.runOnIdle { … } (skydoves hot take #5). The recomposer needs to settle before reading TextFieldState.text.
  • MUST NOT call Thread.sleep to wait for IME events. Compose's idle observation includes the text-input pipeline; the assertion will be ready when runOnIdle returns.
  • MUST NOT simulate text entry by injecting individual Key events through performKeyInput { pressKey(Key.A) } unless the test specifically exercises the hardware-keyboard path. The semantics actions are the canonical IME path.
  • PREFERRED: keep performTextInputSelection calls explicit about relativeToOriginalText. The default (true) is correct for most cases; flip it only when the field installs a VisualTransformation.

Verification

  • Every test that overwrites field content uses performTextReplacement(...) or performTextClearance() followed by performTextInput(...). No back-to-back performTextInput calls expecting replacement semantics.
  • Every performImeAction call targets a field that declares KeyboardOptions(imeAction = ImeAction.Next | Done | Search | …) in production source.
  • State or text assertions following an input action run inside rule.runOnIdle { … }.
  • No Thread.sleep in the test method.
  • ./gradlew :app:connectedDebugAndroidTest (or :app:testDebugUnitTest for Robolectric) passes for the test under change.

References