testing/dart/paragraph_test.dart - mirrors/engine - Git at Google

 // Copyright 2013 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import 'dart:ui';

 import 'package:litetest/litetest.dart';

 void main() {
   // Ahem font uses a constant ideographic/alphabetic baseline ratio.
   const double kAhemBaselineRatio = 1.25;

   test('predictably lays out a single-line paragraph - Ahem', () {
     for (final double fontSize in <double>[10.0, 20.0, 30.0, 40.0]) {
       final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
         fontFamily: 'Ahem',
         fontStyle: FontStyle.normal,
         fontWeight: FontWeight.normal,
         fontSize: fontSize,
       ));
       builder.addText('Test');
       final Paragraph paragraph = builder.build();
       paragraph.layout(const ParagraphConstraints(width: 400.0));

       expect(paragraph.height, closeTo(fontSize, 0.001));
       expect(paragraph.width, closeTo(400.0, 0.001));
       expect(paragraph.minIntrinsicWidth, closeTo(fontSize * 4.0, 0.001));
       expect(paragraph.maxIntrinsicWidth, closeTo(fontSize * 4.0, 0.001));
       expect(paragraph.alphabeticBaseline, closeTo(fontSize * .8, 0.001));
       expect(
         paragraph.ideographicBaseline,
         closeTo(paragraph.alphabeticBaseline * kAhemBaselineRatio, 0.001),
       );
     }
   });

   test('predictably lays out a single-line paragraph - FlutterTest', () {
     for (final double fontSize in <double>[10.0, 20.0, 30.0, 40.0]) {
       final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
         fontFamily: 'FlutterTest',
         fontStyle: FontStyle.normal,
         fontWeight: FontWeight.normal,
         fontSize: fontSize,
       ));
       builder.addText('Test');
       final Paragraph paragraph = builder.build();
       paragraph.layout(const ParagraphConstraints(width: 400.0));

       expect(paragraph.height, fontSize);
       expect(paragraph.width, 400.0);
       expect(paragraph.minIntrinsicWidth, fontSize * 4.0);
       expect(paragraph.maxIntrinsicWidth, fontSize * 4.0);
       expect(paragraph.alphabeticBaseline, fontSize * 0.75);
       expect(paragraph.ideographicBaseline, fontSize);
     }
   });

   test('predictably lays out a multi-line paragraph', () {
     for (final double fontSize in <double>[10.0, 20.0, 30.0, 40.0]) {
       final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
         fontFamily: 'Ahem',
         fontStyle: FontStyle.normal,
         fontWeight: FontWeight.normal,
         fontSize: fontSize,
       ));
       builder.addText('Test Ahem');
       final Paragraph paragraph = builder.build();
       paragraph.layout(ParagraphConstraints(width: fontSize * 5.0));

       expect(paragraph.height, closeTo(fontSize * 2.0, 0.001)); // because it wraps
       expect(paragraph.width, closeTo(fontSize * 5.0, 0.001));
       expect(paragraph.minIntrinsicWidth, closeTo(fontSize * 4.0, 0.001));

       // TODO(yjbanov): see https://github.com/flutter/flutter/issues/21965
       expect(paragraph.maxIntrinsicWidth, closeTo(fontSize * 9.0, 0.001));
       expect(paragraph.alphabeticBaseline, closeTo(fontSize * .8, 0.001));
       expect(
         paragraph.ideographicBaseline,
         closeTo(paragraph.alphabeticBaseline * kAhemBaselineRatio, 0.001),
       );
     }
   });

   test('getLineBoundary', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
       fontFamily: 'Ahem',
       fontStyle: FontStyle.normal,
       fontWeight: FontWeight.normal,
       fontSize: fontSize,
     ));
     builder.addText('Test Ahem');
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: fontSize * 5.0));

     // Wraps to two lines.
     expect(paragraph.height, closeTo(fontSize * 2.0, 0.001));

     const TextPosition wrapPositionDown = TextPosition(
       offset: 5,
     );
     TextRange line = paragraph.getLineBoundary(wrapPositionDown);
     expect(line.start, 5);
     expect(line.end, 9);

     const TextPosition wrapPositionUp = TextPosition(
       offset: 5,
       affinity: TextAffinity.upstream,
     );
     line = paragraph.getLineBoundary(wrapPositionUp);
     expect(line.start, 0);
     expect(line.end, 5);

     const TextPosition wrapPositionStart = TextPosition(
       offset: 0,
     );
     line = paragraph.getLineBoundary(wrapPositionStart);
     expect(line.start, 0);
     expect(line.end, 5);

     const TextPosition wrapPositionEnd = TextPosition(
       offset: 9,
     );
     line = paragraph.getLineBoundary(wrapPositionEnd);
     expect(line.start, 5);
     expect(line.end, 9);
   });

   test('getLineBoundary RTL', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
       fontFamily: 'Ahem',
       fontStyle: FontStyle.normal,
       fontWeight: FontWeight.normal,
       fontSize: fontSize,
       textDirection: TextDirection.rtl,
     ));
     builder.addText('القاهرةالقاهرة');
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: fontSize * 5.0));

     // Wraps to three lines.
     expect(paragraph.height, closeTo(fontSize * 3.0, 0.001));

     const TextPosition wrapPositionDown = TextPosition(
       offset: 5,
     );
     TextRange line = paragraph.getLineBoundary(wrapPositionDown);
     expect(line.start, 5);
     expect(line.end, 10);

     const TextPosition wrapPositionUp = TextPosition(
       offset: 5,
       affinity: TextAffinity.upstream,
     );
     line = paragraph.getLineBoundary(wrapPositionUp);
     expect(line.start, 0);
     expect(line.end, 5);

     const TextPosition wrapPositionStart = TextPosition(
       offset: 0,
     );
     line = paragraph.getLineBoundary(wrapPositionStart);
     expect(line.start, 0);
     expect(line.end, 5);

     const TextPosition wrapPositionEnd = TextPosition(
       offset: 9,
     );
     line = paragraph.getLineBoundary(wrapPositionEnd);
     expect(line.start, 5);
     expect(line.end, 10);
   });

   test('getLineBoundary empty line', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
       fontFamily: 'Ahem',
       fontStyle: FontStyle.normal,
       fontWeight: FontWeight.normal,
       fontSize: fontSize,
       textDirection: TextDirection.rtl,
     ));
     builder.addText('Test\n\nAhem');
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: fontSize * 5.0));

     // Three lines due to line breaks, with the middle line being empty.
     expect(paragraph.height, closeTo(fontSize * 3.0, 0.001));

     const TextPosition emptyLinePosition = TextPosition(
       offset: 5,
     );
     TextRange line = paragraph.getLineBoundary(emptyLinePosition);
     expect(line.start, 5);
     expect(line.end, 5);

     // Since these are hard newlines, TextAffinity has no effect here.
     const TextPosition emptyLinePositionUpstream = TextPosition(
       offset: 5,
       affinity: TextAffinity.upstream,
     );
     line = paragraph.getLineBoundary(emptyLinePositionUpstream);
     expect(line.start, 5);
     expect(line.end, 5);

     const TextPosition endOfFirstLinePosition = TextPosition(
       offset: 4,
     );
     line = paragraph.getLineBoundary(endOfFirstLinePosition);
     expect(line.start, 0);
     expect(line.end, 4);

     const TextPosition startOfLastLinePosition = TextPosition(
       offset: 6,
     );
     line = paragraph.getLineBoundary(startOfLastLinePosition);
     expect(line.start, 6);
     expect(line.end, 10);
   });

   test('getLineMetricsAt', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
       fontSize: fontSize,
       textDirection: TextDirection.rtl,
       height: 2.0,
     ));
     builder.addText('Test\npppp');
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: 100.0));
     final LineMetrics? line = paragraph.getLineMetricsAt(1);
     expect(line?.hardBreak, isTrue);
     expect(line?.ascent, 15.0);
     expect(line?.descent, 5.0);
     expect(line?.height, 20.0);
     expect(line?.width, 4 * 10.0);
     expect(line?.left, 100.0 - 40.0);
     expect(line?.baseline, 20.0 + 15.0);
     expect(line?.lineNumber, 1);
   });

   test('line number', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(fontSize: fontSize));
     builder.addText('Test\n\nTest');
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: 100.0));
     expect(paragraph.numberOfLines, 3);
     expect(paragraph.getLineNumberAt(4), 0); // first LF
     expect(paragraph.getLineNumberAt(5), 1); // second LF
     expect(paragraph.getLineNumberAt(6), 2); // "T" in the second "Test"
   });

   test('empty paragraph', () {
     const double fontSize = 10.0;
     final Paragraph paragraph = ParagraphBuilder(ParagraphStyle(
       fontSize: fontSize,
     )).build();
     paragraph.layout(const ParagraphConstraints(width: double.infinity));

     expect(paragraph.getClosestGlyphInfoForOffset(Offset.zero), isNull);
     expect(paragraph.getGlyphInfoAt(0), isNull);

     expect(paragraph.getLineMetricsAt(0), isNull);
     expect(paragraph.numberOfLines, 0);
     expect(paragraph.getLineNumberAt(0), isNull);

     expect(paragraph.getGlyphInfoAt(0), isNull);
     expect(paragraph.getClosestGlyphInfoForOffset(Offset.zero), isNull);
   });

   test('OOB indices as input', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
       fontSize: fontSize,
       maxLines: 1,
       ellipsis: 'BBB',
     ))..addText('A' * 100);
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: 100));

     expect(paragraph.numberOfLines, 1);

     expect(paragraph.getLineMetricsAt(-1), isNull);
     expect(paragraph.getLineMetricsAt(0)?.lineNumber, 0);
     expect(paragraph.getLineMetricsAt(1), isNull);

     expect(paragraph.getLineNumberAt(-1), isNull);
     expect(paragraph.getLineNumberAt(0), 0);
     expect(paragraph.getLineNumberAt(6), 0);
     // The last 3 characters on the first line are ellipsized with BBB.
     expect(paragraph.getLineMetricsAt(7), isNull);

     expect(paragraph.getGlyphInfoAt(-1), isNull);
     expect(paragraph.getGlyphInfoAt(0)?.graphemeClusterCodeUnitRange, const TextRange(start: 0, end: 1));
     expect(paragraph.getGlyphInfoAt(6)?.graphemeClusterCodeUnitRange, const TextRange(start: 6, end: 7));
     expect(paragraph.getGlyphInfoAt(7), isNull);
     expect(paragraph.getGlyphInfoAt(200), isNull);
   });

   test('querying glyph info', () {
     const double fontSize = 10.0;
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
       fontSize: fontSize,
     ));
     builder.addText('Test\nTest');
     final Paragraph paragraph = builder.build();
     paragraph.layout(const ParagraphConstraints(width: double.infinity));

     final GlyphInfo? bottomRight = paragraph.getClosestGlyphInfoForOffset(const Offset(99.0, 99.0));
     final GlyphInfo? last = paragraph.getGlyphInfoAt(8);
     expect(bottomRight, equals(last));
     expect(bottomRight, notEquals(paragraph.getGlyphInfoAt(0)));

     expect(bottomRight?.graphemeClusterLayoutBounds, const Rect.fromLTWH(30, 10, 10, 10));
     expect(bottomRight?.graphemeClusterCodeUnitRange, const TextRange(start: 8, end: 9));
     expect(bottomRight?.writingDirection, TextDirection.ltr);
   });

   test('painting a disposed paragraph does not crash', () {
     final Paragraph paragraph = ParagraphBuilder(ParagraphStyle()).build();
     paragraph.dispose();

     final PictureRecorder recorder = PictureRecorder();
     final Canvas canvas = Canvas(recorder);

     void callback() { canvas.drawParagraph(paragraph, Offset.zero); }
     if (assertStatementsEnabled) {
       expectAssertion(callback);
     } else {
       expect(callback, throwsStateError);
     }
   });

   test('rounding hack disabled', () {
     const double fontSize = 1.25;
     const String text = '12345';
     assert((fontSize * text.length).truncate() != fontSize * text.length);
     final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(fontSize: fontSize));
     builder.addText(text);
     final Paragraph paragraph = builder.build()
       ..layout(const ParagraphConstraints(width: text.length * fontSize));
     expect(paragraph.maxIntrinsicWidth, text.length * fontSize);
     switch (paragraph.computeLineMetrics()) {
       case [LineMetrics(width: final double width)]:
         expect(width, text.length * fontSize);
       case final List<LineMetrics> metrics:
         expect(metrics, hasLength(1));
     }
   });
 }
	// Copyright 2013 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import 'dart:ui';

	import 'package:litetest/litetest.dart';

	void main() {
	// Ahem font uses a constant ideographic/alphabetic baseline ratio.
	const double kAhemBaselineRatio = 1.25;

	test('predictably lays out a single-line paragraph - Ahem', () {
	for (final double fontSize in <double>[10.0, 20.0, 30.0, 40.0]) {
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontFamily: 'Ahem',
	fontStyle: FontStyle.normal,
	fontWeight: FontWeight.normal,
	fontSize: fontSize,
	));
	builder.addText('Test');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: 400.0));

	expect(paragraph.height, closeTo(fontSize, 0.001));
	expect(paragraph.width, closeTo(400.0, 0.001));
	expect(paragraph.minIntrinsicWidth, closeTo(fontSize * 4.0, 0.001));
	expect(paragraph.maxIntrinsicWidth, closeTo(fontSize * 4.0, 0.001));
	expect(paragraph.alphabeticBaseline, closeTo(fontSize * .8, 0.001));
	expect(
	paragraph.ideographicBaseline,
	closeTo(paragraph.alphabeticBaseline * kAhemBaselineRatio, 0.001),
	);
	}
	});

	test('predictably lays out a single-line paragraph - FlutterTest', () {
	for (final double fontSize in <double>[10.0, 20.0, 30.0, 40.0]) {
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontFamily: 'FlutterTest',
	fontStyle: FontStyle.normal,
	fontWeight: FontWeight.normal,
	fontSize: fontSize,
	));
	builder.addText('Test');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: 400.0));

	expect(paragraph.height, fontSize);
	expect(paragraph.width, 400.0);
	expect(paragraph.minIntrinsicWidth, fontSize * 4.0);
	expect(paragraph.maxIntrinsicWidth, fontSize * 4.0);
	expect(paragraph.alphabeticBaseline, fontSize * 0.75);
	expect(paragraph.ideographicBaseline, fontSize);
	}
	});

	test('predictably lays out a multi-line paragraph', () {
	for (final double fontSize in <double>[10.0, 20.0, 30.0, 40.0]) {
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontFamily: 'Ahem',
	fontStyle: FontStyle.normal,
	fontWeight: FontWeight.normal,
	fontSize: fontSize,
	));
	builder.addText('Test Ahem');
	final Paragraph paragraph = builder.build();
	paragraph.layout(ParagraphConstraints(width: fontSize * 5.0));

	expect(paragraph.height, closeTo(fontSize * 2.0, 0.001)); // because it wraps
	expect(paragraph.width, closeTo(fontSize * 5.0, 0.001));
	expect(paragraph.minIntrinsicWidth, closeTo(fontSize * 4.0, 0.001));

	// TODO(yjbanov): see https://github.com/flutter/flutter/issues/21965
	expect(paragraph.maxIntrinsicWidth, closeTo(fontSize * 9.0, 0.001));
	expect(paragraph.alphabeticBaseline, closeTo(fontSize * .8, 0.001));
	expect(
	paragraph.ideographicBaseline,
	closeTo(paragraph.alphabeticBaseline * kAhemBaselineRatio, 0.001),
	);
	}
	});

	test('getLineBoundary', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontFamily: 'Ahem',
	fontStyle: FontStyle.normal,
	fontWeight: FontWeight.normal,
	fontSize: fontSize,
	));
	builder.addText('Test Ahem');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: fontSize * 5.0));

	// Wraps to two lines.
	expect(paragraph.height, closeTo(fontSize * 2.0, 0.001));

	const TextPosition wrapPositionDown = TextPosition(
	offset: 5,
	);
	TextRange line = paragraph.getLineBoundary(wrapPositionDown);
	expect(line.start, 5);
	expect(line.end, 9);

	const TextPosition wrapPositionUp = TextPosition(
	offset: 5,
	affinity: TextAffinity.upstream,
	);
	line = paragraph.getLineBoundary(wrapPositionUp);
	expect(line.start, 0);
	expect(line.end, 5);

	const TextPosition wrapPositionStart = TextPosition(
	offset: 0,
	);
	line = paragraph.getLineBoundary(wrapPositionStart);
	expect(line.start, 0);
	expect(line.end, 5);

	const TextPosition wrapPositionEnd = TextPosition(
	offset: 9,
	);
	line = paragraph.getLineBoundary(wrapPositionEnd);
	expect(line.start, 5);
	expect(line.end, 9);
	});

	test('getLineBoundary RTL', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontFamily: 'Ahem',
	fontStyle: FontStyle.normal,
	fontWeight: FontWeight.normal,
	fontSize: fontSize,
	textDirection: TextDirection.rtl,
	));
	builder.addText('القاهرةالقاهرة');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: fontSize * 5.0));

	// Wraps to three lines.
	expect(paragraph.height, closeTo(fontSize * 3.0, 0.001));

	const TextPosition wrapPositionDown = TextPosition(
	offset: 5,
	);
	TextRange line = paragraph.getLineBoundary(wrapPositionDown);
	expect(line.start, 5);
	expect(line.end, 10);

	const TextPosition wrapPositionUp = TextPosition(
	offset: 5,
	affinity: TextAffinity.upstream,
	);
	line = paragraph.getLineBoundary(wrapPositionUp);
	expect(line.start, 0);
	expect(line.end, 5);

	const TextPosition wrapPositionStart = TextPosition(
	offset: 0,
	);
	line = paragraph.getLineBoundary(wrapPositionStart);
	expect(line.start, 0);
	expect(line.end, 5);

	const TextPosition wrapPositionEnd = TextPosition(
	offset: 9,
	);
	line = paragraph.getLineBoundary(wrapPositionEnd);
	expect(line.start, 5);
	expect(line.end, 10);
	});

	test('getLineBoundary empty line', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontFamily: 'Ahem',
	fontStyle: FontStyle.normal,
	fontWeight: FontWeight.normal,
	fontSize: fontSize,
	textDirection: TextDirection.rtl,
	));
	builder.addText('Test\n\nAhem');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: fontSize * 5.0));

	// Three lines due to line breaks, with the middle line being empty.
	expect(paragraph.height, closeTo(fontSize * 3.0, 0.001));

	const TextPosition emptyLinePosition = TextPosition(
	offset: 5,
	);
	TextRange line = paragraph.getLineBoundary(emptyLinePosition);
	expect(line.start, 5);
	expect(line.end, 5);

	// Since these are hard newlines, TextAffinity has no effect here.
	const TextPosition emptyLinePositionUpstream = TextPosition(
	offset: 5,
	affinity: TextAffinity.upstream,
	);
	line = paragraph.getLineBoundary(emptyLinePositionUpstream);
	expect(line.start, 5);
	expect(line.end, 5);

	const TextPosition endOfFirstLinePosition = TextPosition(
	offset: 4,
	);
	line = paragraph.getLineBoundary(endOfFirstLinePosition);
	expect(line.start, 0);
	expect(line.end, 4);

	const TextPosition startOfLastLinePosition = TextPosition(
	offset: 6,
	);
	line = paragraph.getLineBoundary(startOfLastLinePosition);
	expect(line.start, 6);
	expect(line.end, 10);
	});

	test('getLineMetricsAt', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontSize: fontSize,
	textDirection: TextDirection.rtl,
	height: 2.0,
	));
	builder.addText('Test\npppp');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: 100.0));
	final LineMetrics? line = paragraph.getLineMetricsAt(1);
	expect(line?.hardBreak, isTrue);
	expect(line?.ascent, 15.0);
	expect(line?.descent, 5.0);
	expect(line?.height, 20.0);
	expect(line?.width, 4 * 10.0);
	expect(line?.left, 100.0 - 40.0);
	expect(line?.baseline, 20.0 + 15.0);
	expect(line?.lineNumber, 1);
	});

	test('line number', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(fontSize: fontSize));
	builder.addText('Test\n\nTest');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: 100.0));
	expect(paragraph.numberOfLines, 3);
	expect(paragraph.getLineNumberAt(4), 0); // first LF
	expect(paragraph.getLineNumberAt(5), 1); // second LF
	expect(paragraph.getLineNumberAt(6), 2); // "T" in the second "Test"
	});

	test('empty paragraph', () {
	const double fontSize = 10.0;
	final Paragraph paragraph = ParagraphBuilder(ParagraphStyle(
	fontSize: fontSize,
	)).build();
	paragraph.layout(const ParagraphConstraints(width: double.infinity));

	expect(paragraph.getClosestGlyphInfoForOffset(Offset.zero), isNull);
	expect(paragraph.getGlyphInfoAt(0), isNull);

	expect(paragraph.getLineMetricsAt(0), isNull);
	expect(paragraph.numberOfLines, 0);
	expect(paragraph.getLineNumberAt(0), isNull);

	expect(paragraph.getGlyphInfoAt(0), isNull);
	expect(paragraph.getClosestGlyphInfoForOffset(Offset.zero), isNull);
	});

	test('OOB indices as input', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontSize: fontSize,
	maxLines: 1,
	ellipsis: 'BBB',
	))..addText('A' * 100);
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: 100));

	expect(paragraph.numberOfLines, 1);

	expect(paragraph.getLineMetricsAt(-1), isNull);
	expect(paragraph.getLineMetricsAt(0)?.lineNumber, 0);
	expect(paragraph.getLineMetricsAt(1), isNull);

	expect(paragraph.getLineNumberAt(-1), isNull);
	expect(paragraph.getLineNumberAt(0), 0);
	expect(paragraph.getLineNumberAt(6), 0);
	// The last 3 characters on the first line are ellipsized with BBB.
	expect(paragraph.getLineMetricsAt(7), isNull);

	expect(paragraph.getGlyphInfoAt(-1), isNull);
	expect(paragraph.getGlyphInfoAt(0)?.graphemeClusterCodeUnitRange, const TextRange(start: 0, end: 1));
	expect(paragraph.getGlyphInfoAt(6)?.graphemeClusterCodeUnitRange, const TextRange(start: 6, end: 7));
	expect(paragraph.getGlyphInfoAt(7), isNull);
	expect(paragraph.getGlyphInfoAt(200), isNull);
	});

	test('querying glyph info', () {
	const double fontSize = 10.0;
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(
	fontSize: fontSize,
	));
	builder.addText('Test\nTest');
	final Paragraph paragraph = builder.build();
	paragraph.layout(const ParagraphConstraints(width: double.infinity));

	final GlyphInfo? bottomRight = paragraph.getClosestGlyphInfoForOffset(const Offset(99.0, 99.0));
	final GlyphInfo? last = paragraph.getGlyphInfoAt(8);
	expect(bottomRight, equals(last));
	expect(bottomRight, notEquals(paragraph.getGlyphInfoAt(0)));

	expect(bottomRight?.graphemeClusterLayoutBounds, const Rect.fromLTWH(30, 10, 10, 10));
	expect(bottomRight?.graphemeClusterCodeUnitRange, const TextRange(start: 8, end: 9));
	expect(bottomRight?.writingDirection, TextDirection.ltr);
	});

	test('painting a disposed paragraph does not crash', () {
	final Paragraph paragraph = ParagraphBuilder(ParagraphStyle()).build();
	paragraph.dispose();

	final PictureRecorder recorder = PictureRecorder();
	final Canvas canvas = Canvas(recorder);

	void callback() { canvas.drawParagraph(paragraph, Offset.zero); }
	if (assertStatementsEnabled) {
	expectAssertion(callback);
	} else {
	expect(callback, throwsStateError);
	}
	});

	test('rounding hack disabled', () {
	const double fontSize = 1.25;
	const String text = '12345';
	assert((fontSize * text.length).truncate() != fontSize * text.length);
	final ParagraphBuilder builder = ParagraphBuilder(ParagraphStyle(fontSize: fontSize));
	builder.addText(text);
	final Paragraph paragraph = builder.build()
	..layout(const ParagraphConstraints(width: text.length * fontSize));
	expect(paragraph.maxIntrinsicWidth, text.length * fontSize);
	switch (paragraph.computeLineMetrics()) {
	case [LineMetrics(width: final double width)]:
	expect(width, text.length * fontSize);
	case final List<LineMetrics> metrics:
	expect(metrics, hasLength(1));
	}
	});
	}