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Commit 4de5306e authored by Chris.CC Lee's avatar Chris.CC Lee
Browse files

Refine surrounding text logic and test case readability. 

1. Follow up refinement for CL[1].
2. Test case to verify the InitialSurroundingText parcel
wrapping/unwrapping logic.

[1] c486acc4, Ie04f2349b1157408aa8ed9044aea12ce99132cb4

Bug: 148035211
Test: atest FrameworksCoreTests:EditorInfoTest
Change-Id: I9609b8a7dabb6285ed673cb0890bb3019e3b7caa
parent aa6753b9

core/java/android/view/inputmethod/EditorInfo.java

+43 −33
Original line number Diff line number Diff line
@@ -33,11 +33,11 @@ import android.util.Printer; 
import android.view.View;



import com.android.internal.annotations.VisibleForTesting;

import com.android.internal.util.Preconditions;



import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.util.Arrays;

import java.util.Objects;



/**

 * An EditorInfo describes several attributes of a text editing object
@@ -558,7 +558,7 @@ public class EditorInfo implements InputType, Parcelable { 
     *                      editor wants to trim out the first 10 chars, subTextStart should be 10.

     */

    public void setInitialSurroundingSubText(@NonNull CharSequence subText, int subTextStart) {

        Preconditions.checkNotNull(subText);

        Objects.requireNonNull(subText);



        // Swap selection start and end if necessary.

        final int subTextSelStart = initialSelStart > initialSelEnd
@@ -585,25 +585,35 @@ public class EditorInfo implements InputType, Parcelable { 
            return;

        }



        // The input text is too long. Let's try to trim it reasonably. Fundamental rules are:

        // 1. Text before the cursor is the most important information to IMEs.

        // 2. Text after the cursor is the second important information to IMEs.

        // 3. Selected text is the least important information but it shall NEVER be truncated.

        //    When it is too long, just drop it.

        //

        // Source: <TextBeforeCursor><Selection><TextAfterCursor>

        // Possible results:

        // 1. <(maybeTrimmedAtHead)TextBeforeCursor><Selection><TextAfterCursor(maybeTrimmedAtTail)>

        // 2. <(maybeTrimmedAtHead)TextBeforeCursor><TextAfterCursor(maybeTrimmedAtTail)>

        //

        final int sourceSelLength = subTextSelEnd - subTextSelStart;

        trimLongSurroundingText(subText, subTextSelStart, subTextSelEnd);

    }



    /**

     * Trims the initial surrounding text when it is over sized. Fundamental trimming rules are:

     * - The text before the cursor is the most important information to IMEs.

     * - The text after the cursor is the second important information to IMEs.

     * - The selected text is the least important information but it shall NEVER be truncated. When

     *    it is too long, just drop it.

     *<p><pre>

     * For example, the subText can be viewed as

     *     TextBeforeCursor + Selection + TextAfterCursor

     * The result could be

     *     1. (maybeTrimmedAtHead)TextBeforeCursor + Selection + TextAfterCursor(maybeTrimmedAtTail)

     *     2. (maybeTrimmedAtHead)TextBeforeCursor + TextAfterCursor(maybeTrimmedAtTail)</pre>

     *

     * @param subText The long text that needs to be trimmed.

     * @param selStart The text offset of the start of the selection.

     * @param selEnd The text offset of the end of the selection

     */

    private void trimLongSurroundingText(CharSequence subText, int selStart, int selEnd) {

        final int sourceSelLength = selEnd - selStart;

        // When the selected text is too long, drop it.

        final int newSelLength = (sourceSelLength > MAX_INITIAL_SELECTION_LENGTH)

                ? 0 : sourceSelLength;



        // Distribute rest of length quota to TextBeforeCursor and TextAfterCursor in 4:1 ratio.

        final int subTextBeforeCursorLength = subTextSelStart;

        final int subTextAfterCursorLength = subTextLength - subTextSelEnd;

        final int subTextBeforeCursorLength = selStart;

        final int subTextAfterCursorLength = subText.length() - selEnd;

        final int maxLengthMinusSelection = MEMORY_EFFICIENT_TEXT_LENGTH - newSelLength;

        final int possibleMaxBeforeCursorLength =

                Math.min(subTextBeforeCursorLength, (int) (0.8 * maxLengthMinusSelection));
@@ -617,24 +627,23 @@ public class EditorInfo implements InputType, Parcelable { 


        // We don't want to cut surrogate pairs in the middle. Exam that at the new head and tail.

        if (isCutOnSurrogate(subText,

                subTextSelStart - newBeforeCursorLength, TrimPolicy.HEAD)) {

                selStart - newBeforeCursorLength, TrimPolicy.HEAD)) {

            newBeforeCursorHead = newBeforeCursorHead + 1;

            newBeforeCursorLength = newBeforeCursorLength - 1;

        }

        if (isCutOnSurrogate(subText,

                subTextSelEnd + newAfterCursorLength - 1, TrimPolicy.TAIL)) {

                selEnd + newAfterCursorLength - 1, TrimPolicy.TAIL)) {

            newAfterCursorLength = newAfterCursorLength - 1;

        }



        // Now we know where to trim, compose the initialSurroundingText.

        final int newTextLength = newBeforeCursorLength + newSelLength + newAfterCursorLength;

        CharSequence newInitialSurroundingText;

        final CharSequence newInitialSurroundingText;

        if (newSelLength != sourceSelLength) {

            final CharSequence beforeCursor = subText.subSequence(newBeforeCursorHead,

                    newBeforeCursorHead + newBeforeCursorLength);



            final CharSequence afterCursor = subText.subSequence(subTextSelEnd,

                    subTextSelEnd + newAfterCursorLength);

            final CharSequence afterCursor = subText.subSequence(selEnd,

                    selEnd + newAfterCursorLength);



            newInitialSurroundingText = TextUtils.concat(beforeCursor, afterCursor);

        } else {
@@ -651,15 +660,16 @@ public class EditorInfo implements InputType, Parcelable { 
    }



    /**

     * Get <var>n</var> characters of text before the current cursor position. May be {@code null}

     * when the protocol is not supported.

     * Get <var>length</var> characters of text before the current cursor position. May be

     * {@code null} when the protocol is not supported.

     *

     * @param length The expected length of the text.

     * @param flags Supplies additional options controlling how the text is returned. May be

     * either 0 or {@link InputConnection#GET_TEXT_WITH_STYLES}.

     * @return the text before the cursor position; the length of the returned text might be less

     * than <var>n</var>. When there is no text before the cursor, an empty string will be returned.

     * It could also be {@code null} when the editor or system could not support this protocol.

     * than <var>length</var>. When there is no text before the cursor, an empty string will be

     * returned. It could also be {@code null} when the editor or system could not support this

     * protocol.

     */

    @Nullable

    public CharSequence getInitialTextBeforeCursor(int length, int flags) {
@@ -667,8 +677,8 @@ public class EditorInfo implements InputType, Parcelable { 
    }



    /**

     * Gets the selected text, if any. May be {@code null} when no text is selected or the selected

     * text is way too long.

     * Gets the selected text, if any. May be {@code null} when the protocol is not supported or the

     * selected text is way too long.

     *

     * @param flags Supplies additional options controlling how the text is returned. May be

     * either 0 or {@link InputConnection#GET_TEXT_WITH_STYLES}.
@@ -693,15 +703,16 @@ public class EditorInfo implements InputType, Parcelable { 
    }



    /**

     * Get <var>n</var> characters of text after the current cursor position. May be {@code null}

     * when the protocol is not supported.

     * Get <var>length</var> characters of text after the current cursor position. May be

     * {@code null} when the protocol is not supported.

     *

     * @param length The expected length of the text.

     * @param flags Supplies additional options controlling how the text is returned. May be

     * either 0 or {@link InputConnection#GET_TEXT_WITH_STYLES}.

     * @return the text after the cursor position; the length of the returned text might be less

     * than <var>n</var>. When there is no text after the cursor, an empty string will be returned.

     * It could also be {@code null} when the editor or system could not support this protocol.

     * than <var>length</var>. When there is no text after the cursor, an empty string will be

     * returned. It could also be {@code null} when the editor or system could not support this

     * protocol.

     */

    @Nullable

    public CharSequence getInitialTextAfterCursor(int length, int flags) {
@@ -863,7 +874,6 @@ public class EditorInfo implements InputType, Parcelable { 
        return 0;

    }



    // TODO(b/148035211): Unit tests for this class

    static final class InitialSurroundingText implements Parcelable {

        @Nullable final CharSequence mSurroundingText;

        final int mSelectionHead;

core/tests/coretests/src/android/view/inputmethod/EditorInfoTest.java

+105 −95
Original line number Diff line number Diff line
@@ -20,11 +20,11 @@ import static org.junit.Assert.assertEquals; 
import static org.junit.Assert.assertNull;

import static org.junit.Assert.assertTrue;

import static org.junit.Assert.fail;

import static org.mockito.ArgumentMatchers.anyInt;



import android.annotation.Nullable;

import android.os.Parcel;

import android.os.UserHandle;

import android.text.Spannable;

import android.text.SpannableStringBuilder;

import android.text.TextUtils;
@@ -41,6 +41,7 @@ import org.junit.runner.RunWith; 
@RunWith(AndroidJUnit4.class)

public class EditorInfoTest {

    private static final int TEST_USER_ID = 42;

    private static final int LONG_EXP_TEXT_LENGTH = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH * 2;



    /**

     * Makes sure that {@code null} {@link EditorInfo#targetInputMethodUser} can be copied via
@@ -79,8 +80,8 @@ public class EditorInfoTest { 
    }



    @Test

    public void testNullTextInputComposeInitialSurroundingText() {

        final Spannable testText = null;

    public void setInitialText_nullInputText_throwsException() {

        final CharSequence testText = null;

        final EditorInfo editorInfo = new EditorInfo();



        try {
@@ -92,56 +93,75 @@ public class EditorInfoTest { 
    }



    @Test

    public void testNonNullTextInputComposeInitialSurroundingText() {

        final Spannable testText = createTestText(/* prependLength= */ 0,

                EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final EditorInfo editorInfo = new EditorInfo();

    public void setInitialText_cursorAtHead_dividesByCursorPosition() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);



        // Cursor at position 0.

        int selectionLength = 0;

        final EditorInfo editorInfo = new EditorInfo();

        final int selectionLength = 0;

        editorInfo.initialSelStart = 0;

        editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;

        int expectedTextBeforeCursorLength = 0;

        int expectedTextAfterCursorLength = testText.length();

        final int expectedTextBeforeCursorLength = 0;

        final int expectedTextAfterCursorLength = testText.length();



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);

    }



        // Cursor at the end.

    @Test

    public void setInitialText_cursorAtTail_dividesByCursorPosition() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final EditorInfo editorInfo = new EditorInfo();

        final int selectionLength = 0;

        editorInfo.initialSelStart = testText.length() - selectionLength;

        editorInfo.initialSelEnd = testText.length();

        expectedTextBeforeCursorLength = testText.length();

        expectedTextAfterCursorLength = 0;

        final int expectedTextBeforeCursorLength = testText.length();

        final int expectedTextAfterCursorLength = 0;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);

    }



        // Cursor at the middle.

        selectionLength = 2;

    @Test

    public void setInitialText_cursorAtMiddle_dividesByCursorPosition() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final EditorInfo editorInfo = new EditorInfo();

        final int selectionLength = 2;

        editorInfo.initialSelStart = testText.length() / 2;

        editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;

        expectedTextBeforeCursorLength = editorInfo.initialSelStart;

        expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;

        final int expectedTextBeforeCursorLength = editorInfo.initialSelStart;

        final int expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);

    }



        // Accidentally swap selection start and end.

    @Test

    public void setInitialText_incorrectCursorOrder_correctsThenDivide() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final EditorInfo editorInfo = new EditorInfo();

        final int selectionLength = 2;

        editorInfo.initialSelEnd = testText.length() / 2;

        editorInfo.initialSelStart = editorInfo.initialSelEnd + selectionLength;

        final int expectedTextBeforeCursorLength = testText.length() / 2;

        final int expectedTextAfterCursorLength = testText.length() - testText.length() / 2

                - selectionLength;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);

    }



        // Invalid cursor position.

    @Test

    public void setInitialText_invalidCursorPosition_returnsNull() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final EditorInfo editorInfo = new EditorInfo();

        editorInfo.initialSelStart = -1;



        editorInfo.setInitialSurroundingText(testText);
@@ -153,64 +173,33 @@ public class EditorInfoTest { 
    }



    @Test

    public void testTooLongTextInputComposeInitialSurroundingText() {

        final Spannable testText = createTestText(/* prependLength= */ 0,

                EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH + 2);

    public void setOverSizeInitialText_cursorAtMiddle_dividesProportionately() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH + 2);

        final EditorInfo editorInfo = new EditorInfo();



        // Cursor at position 0.

        int selectionLength = 0;

        editorInfo.initialSelStart = 0;

        editorInfo.initialSelEnd = 0 + selectionLength;

        int expectedTextBeforeCursorLength = 0;

        int expectedTextAfterCursorLength = editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);



        // Cursor at the end.

        editorInfo.initialSelStart = testText.length() - selectionLength;

        editorInfo.initialSelEnd = testText.length();

        expectedTextBeforeCursorLength = editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH;

        expectedTextAfterCursorLength = 0;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);



        // Cursor at the middle.

        selectionLength = 2;

        final int selectionLength = 2;

        editorInfo.initialSelStart = testText.length() / 2;

        editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;

        expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,

        final int expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,

                (int) (0.8 * (EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH - selectionLength)));

        expectedTextAfterCursorLength = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH

        final int expectedTextAfterCursorLength = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH

                - expectedTextBeforeCursorLength - selectionLength;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);

    }



        // Accidentally swap selection start and end.

        editorInfo.initialSelEnd = testText.length() / 2;

        editorInfo.initialSelStart = editorInfo.initialSelEnd + selectionLength;



        editorInfo.setInitialSurroundingText(testText);



        assertExpectedTextLength(editorInfo, expectedTextBeforeCursorLength, selectionLength,

                expectedTextAfterCursorLength);



        // Selection too long, selected text should be dropped.

        selectionLength = EditorInfo.MAX_INITIAL_SELECTION_LENGTH + 1;

    @Test

    public void setOverSizeInitialText_overSizeSelection_dropsSelection() {

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH + 2);

        final EditorInfo editorInfo = new EditorInfo();

        final int selectionLength = EditorInfo.MAX_INITIAL_SELECTION_LENGTH + 1;

        editorInfo.initialSelStart = testText.length() / 2;

        editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;

        expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,

        final int expectedTextBeforeCursorLength = Math.min(editorInfo.initialSelStart,

                (int) (0.8 * EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH));

        expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;

        final int expectedTextAfterCursorLength = testText.length() - editorInfo.initialSelEnd;



        editorInfo.setInitialSurroundingText(testText);
@@ -219,34 +208,59 @@ public class EditorInfoTest { 
    }



    @Test

    public void testTooLongSubTextInputComposeInitialSurroundingText() {

        final int prependLength = 5;

        final int subTextLength = EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH;

        final Spannable fullText = createTestText(prependLength, subTextLength);

    public void setInitialSubText_trimmedSubText_dividesByOriginalCursorPosition() {

        final String prefixString = "prefix";

        final CharSequence subText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final CharSequence originalText = TextUtils.concat(prefixString, subText);

        final EditorInfo editorInfo = new EditorInfo();

        // Cursor at the middle.

        final int selectionLength = 2;

        editorInfo.initialSelStart = fullText.length() / 2;

        editorInfo.initialSelEnd = editorInfo.initialSelStart + selectionLength;

        // #prependLength characters will be trimmed out.

        final Spannable expectedTextBeforeCursor = createExpectedText(/* startNumber= */0,

                editorInfo.initialSelStart - prependLength);

        final Spannable expectedSelectedText = createExpectedText(

                editorInfo.initialSelStart - prependLength, selectionLength);

        final Spannable expectedTextAfterCursor = createExpectedText(

                editorInfo.initialSelEnd - prependLength,

                fullText.length() - editorInfo.initialSelEnd);



        editorInfo.setInitialSurroundingSubText(fullText.subSequence(prependLength,

                fullText.length()), prependLength);

        final int selLength = 2;

        editorInfo.initialSelStart = originalText.length() / 2;

        editorInfo.initialSelEnd = editorInfo.initialSelStart + selLength;

        final CharSequence expectedTextBeforeCursor = createExpectedText(/* startNumber= */0,

                editorInfo.initialSelStart - prefixString.length());

        final CharSequence expectedSelectedText = createExpectedText(

                editorInfo.initialSelStart - prefixString.length(), selLength);

        final CharSequence expectedTextAfterCursor = createExpectedText(

                editorInfo.initialSelEnd - prefixString.length(),

                originalText.length() - editorInfo.initialSelEnd);



        editorInfo.setInitialSurroundingSubText(subText, prefixString.length());



        assertTrue(TextUtils.equals(expectedTextBeforeCursor,

                editorInfo.getInitialTextBeforeCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES)));

                editorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH, anyInt())));

        assertTrue(TextUtils.equals(expectedSelectedText,

                editorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES)));

                editorInfo.getInitialSelectedText(anyInt())));

        assertTrue(TextUtils.equals(expectedTextAfterCursor,

                editorInfo.getInitialTextAfterCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,

                editorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH, anyInt())));

    }



    @Test

    public void initialSurroundingText_wrapIntoParcel_staysIntact() {

        // EditorInfo.InitialSurroundingText is not visible to test class. But all its key elements

        // must stay intact for its getter methods to return correct value and it will be wrapped

        // into its outer class for parcel transfer, therefore we can verify its parcel

        // wrapping/unwrapping logic through its outer class.

        final CharSequence testText = createTestText(EditorInfo.MEMORY_EFFICIENT_TEXT_LENGTH);

        final EditorInfo sourceEditorInfo = new EditorInfo();

        final int selectionLength = 2;

        sourceEditorInfo.initialSelStart = testText.length() / 2;

        sourceEditorInfo.initialSelEnd = sourceEditorInfo.initialSelStart + selectionLength;

        sourceEditorInfo.setInitialSurroundingText(testText);



        final EditorInfo targetEditorInfo = cloneViaParcel(sourceEditorInfo);



        assertTrue(TextUtils.equals(

                sourceEditorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES),

                targetEditorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES)));

        assertTrue(TextUtils.equals(

                sourceEditorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES),

                targetEditorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES)));

        assertTrue(TextUtils.equals(

                sourceEditorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES),

                targetEditorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES)));

    }
@@ -254,12 +268,12 @@ public class EditorInfoTest { 
            @Nullable Integer expectBeforeCursorLength, @Nullable Integer expectSelectionLength,

            @Nullable Integer expectAfterCursorLength) {

        final CharSequence textBeforeCursor =

                editorInfo.getInitialTextBeforeCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,

                editorInfo.getInitialTextBeforeCursor(LONG_EXP_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES);

        final CharSequence selectedText =

                editorInfo.getInitialSelectedText(InputConnection.GET_TEXT_WITH_STYLES);

        final CharSequence textAfterCursor =

                editorInfo.getInitialTextAfterCursor(editorInfo.MEMORY_EFFICIENT_TEXT_LENGTH,

                editorInfo.getInitialTextAfterCursor(LONG_EXP_TEXT_LENGTH,

                        InputConnection.GET_TEXT_WITH_STYLES);



        if (expectBeforeCursorLength == null) {
@@ -281,19 +295,15 @@ public class EditorInfoTest { 
        }

    }



    private static Spannable createTestText(int prependLength, int surroundingLength) {

    private static CharSequence createTestText(int surroundingLength) {

        final SpannableStringBuilder builder = new SpannableStringBuilder();

        for (int i = 0; i < prependLength; i++) {

            builder.append("a");

        }



        for (int i = 0; i < surroundingLength; i++) {

            builder.append(Integer.toString(i % 10));

        }

        return builder;

    }



    private static Spannable createExpectedText(int startNumber, int length) {

    private static CharSequence createExpectedText(int startNumber, int length) {

        final SpannableStringBuilder builder = new SpannableStringBuilder();

        for (int i = startNumber; i < startNumber + length; i++) {

            builder.append(Integer.toString(i % 10));