angular-cn/packages/compiler-cli/ngcc/test/sourcemaps/source_file_spec.ts

538 lines
27 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {encode} from 'sourcemap-codec';
import {absoluteFrom} from '../../../src/ngtsc/file_system';
import {runInEachFileSystem} from '../../../src/ngtsc/file_system/testing';
import {RawSourceMap} from '../../src/sourcemaps/raw_source_map';
import {SegmentMarker} from '../../src/sourcemaps/segment_marker';
import {computeStartOfLinePositions, ensureOriginalSegmentLinks, extractOriginalSegments, findLastMappingIndexBefore, Mapping, parseMappings, SourceFile} from '../../src/sourcemaps/source_file';
runInEachFileSystem(() => {
describe('SourceFile and utilities', () => {
let _: typeof absoluteFrom;
beforeEach(() => {
_ = absoluteFrom;
});
describe('parseMappings()', () => {
it('should be an empty array for source files with no source map', () => {
const mappings = parseMappings(null, [], []);
expect(mappings).toEqual([]);
});
it('should be empty array for source files with no source map mappings', () => {
const rawSourceMap: RawSourceMap = {mappings: '', names: [], sources: [], version: 3};
const mappings = parseMappings(rawSourceMap, [], []);
expect(mappings).toEqual([]);
});
it('should parse the mappings from the raw source map', () => {
const rawSourceMap: RawSourceMap = {
mappings: encode([[[0, 0, 0, 0], [6, 0, 0, 3]]]),
names: [],
sources: ['a.js'],
version: 3
};
const originalSource = new SourceFile(_('/foo/src/a.js'), 'abcdefg', null, false, []);
const mappings = parseMappings(rawSourceMap, [originalSource], [0, 8]);
expect(mappings).toEqual([
{
generatedSegment: {line: 0, column: 0, position: 0, next: undefined},
originalSource,
originalSegment: {line: 0, column: 0, position: 0, next: undefined},
name: undefined
},
{
generatedSegment: {line: 0, column: 6, position: 6, next: undefined},
originalSource,
originalSegment: {line: 0, column: 3, position: 3, next: undefined},
name: undefined
},
]);
});
});
describe('extractOriginalSegments()', () => {
it('should return an empty Map for source files with no source map', () => {
expect(extractOriginalSegments(parseMappings(null, [], []))).toEqual(new Map());
});
it('should be empty Map for source files with no source map mappings', () => {
const rawSourceMap: RawSourceMap = {mappings: '', names: [], sources: [], version: 3};
expect(extractOriginalSegments(parseMappings(rawSourceMap, [], []))).toEqual(new Map());
});
it('should parse the segments in ascending order of original position from the raw source map',
() => {
const originalSource = new SourceFile(_('/foo/src/a.js'), 'abcdefg', null, false, []);
const rawSourceMap: RawSourceMap = {
mappings: encode([[[0, 0, 0, 0], [2, 0, 0, 3], [4, 0, 0, 2]]]),
names: [],
sources: ['a.js'],
version: 3
};
const originalSegments =
extractOriginalSegments(parseMappings(rawSourceMap, [originalSource], [0, 8]));
expect(originalSegments.get(originalSource)).toEqual([
{line: 0, column: 0, position: 0, next: undefined},
{line: 0, column: 2, position: 2, next: undefined},
{line: 0, column: 3, position: 3, next: undefined},
]);
});
it('should create separate arrays for each original source file', () => {
const sourceA = new SourceFile(_('/foo/src/a.js'), 'abcdefg', null, false, []);
const sourceB = new SourceFile(_('/foo/src/b.js'), '1234567', null, false, []);
const rawSourceMap: RawSourceMap = {
mappings:
encode([[[0, 0, 0, 0], [2, 1, 0, 3], [4, 0, 0, 2], [5, 1, 0, 5], [6, 1, 0, 2]]]),
names: [],
sources: ['a.js', 'b.js'],
version: 3
};
const originalSegments =
extractOriginalSegments(parseMappings(rawSourceMap, [sourceA, sourceB], [0, 8]));
expect(originalSegments.get(sourceA)).toEqual([
{line: 0, column: 0, position: 0, next: undefined},
{line: 0, column: 2, position: 2, next: undefined},
]);
expect(originalSegments.get(sourceB)).toEqual([
{line: 0, column: 2, position: 2, next: undefined},
{line: 0, column: 3, position: 3, next: undefined},
{line: 0, column: 5, position: 5, next: undefined},
]);
});
});
describe('findLastMappingIndexBefore', () => {
it('should find the highest mapping index that has a segment marker below the given one if there is not an exact match',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 35, position: 35, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 0);
expect(index).toEqual(2);
});
it('should find the highest mapping index that has a segment marker (when there are duplicates) below the given one if there is not an exact match',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 30, position: 30, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 35, position: 35, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 0);
expect(index).toEqual(3);
});
it('should find the last mapping if the segment marker is higher than all of them', () => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 60, position: 60, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 0);
expect(index).toEqual(4);
});
it('should return -1 if the segment marker is lower than all of them', () => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 5, position: 5, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 0);
expect(index).toEqual(-1);
});
describe('[exact match inclusive]', () => {
it('should find the matching segment marker mapping index if there is only one of them',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const index = findLastMappingIndexBefore(mappings, marker3, /* exclusive */ false, 0);
expect(index).toEqual(2);
});
it('should find the highest matching segment marker mapping index if there is more than one of them',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 30, position: 30, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const index = findLastMappingIndexBefore(mappings, marker3, /* exclusive */ false, 0);
expect(index).toEqual(3);
});
});
describe('[exact match exclusive]', () => {
it('should find the preceding mapping index if there is a matching segment marker', () => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const index = findLastMappingIndexBefore(mappings, marker3, /* exclusive */ true, 0);
expect(index).toEqual(1);
});
it('should find the highest preceding mapping index if there is more than one matching segment marker',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 30, position: 30, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const index = findLastMappingIndexBefore(mappings, marker3, /* exclusive */ false, 0);
expect(index).toEqual(3);
});
});
describe('[with lowerIndex hint', () => {
it('should find the highest mapping index above the lowerIndex hint that has a segment marker below the given one if there is not an exact match',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 35, position: 35, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 1);
expect(index).toEqual(2);
});
it('should return the lowerIndex mapping index if there is a single exact match and we are not exclusive',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 30, position: 30, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 2);
expect(index).toEqual(2);
});
it('should return the lowerIndex mapping index if there are multiple exact matches and we are not exclusive',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 30, position: 30, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 30, position: 30, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 3);
expect(index).toEqual(3);
});
it('should return -1 if the segment marker is lower than the lowerIndex hint', () => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 25, position: 25, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ false, 2);
expect(index).toEqual(-1);
});
it('should return -1 if the segment marker is equal to the lowerIndex hint and we are exclusive',
() => {
const marker5: SegmentMarker = {line: 0, column: 50, position: 50, next: undefined};
const marker4: SegmentMarker = {line: 0, column: 40, position: 40, next: marker5};
const marker3: SegmentMarker = {line: 0, column: 30, position: 30, next: marker4};
const marker2: SegmentMarker = {line: 0, column: 20, position: 20, next: marker3};
const marker1: SegmentMarker = {line: 0, column: 10, position: 10, next: marker2};
const mappings: Mapping[] = [marker1, marker2, marker3, marker4, marker5].map(
marker => ({generatedSegment: marker} as Mapping));
const marker: SegmentMarker = {line: 0, column: 30, position: 30, next: undefined};
const index = findLastMappingIndexBefore(mappings, marker, /* exclusive */ true, 2);
expect(index).toEqual(-1);
});
});
});
describe('ensureOriginalSegmentLinks', () => {
it('should add `next` properties to each segment that point to the next segment in the same source file',
() => {
const sourceA = new SourceFile(_('/foo/src/a.js'), 'abcdefg', null, false, []);
const sourceB = new SourceFile(_('/foo/src/b.js'), '1234567', null, false, []);
const rawSourceMap: RawSourceMap = {
mappings:
encode([[[0, 0, 0, 0], [2, 1, 0, 3], [4, 0, 0, 2], [5, 1, 0, 5], [6, 1, 0, 2]]]),
names: [],
sources: ['a.js', 'b.js'],
version: 3
};
const mappings = parseMappings(rawSourceMap, [sourceA, sourceB], [0, 8]);
ensureOriginalSegmentLinks(mappings);
expect(mappings[0].originalSegment.next).toBe(mappings[2].originalSegment);
expect(mappings[1].originalSegment.next).toBe(mappings[3].originalSegment);
expect(mappings[2].originalSegment.next).toBeUndefined();
expect(mappings[3].originalSegment.next).toBeUndefined();
expect(mappings[4].originalSegment.next).toBe(mappings[1].originalSegment);
});
});
describe('SourceFile', () => {
describe('flattenedMappings', () => {
it('should be an empty array for source files with no source map', () => {
const sourceFile =
new SourceFile(_('/foo/src/index.js'), 'index contents', null, false, []);
expect(sourceFile.flattenedMappings).toEqual([]);
});
it('should be empty array for source files with no source map mappings', () => {
const rawSourceMap: RawSourceMap = {mappings: '', names: [], sources: [], version: 3};
const sourceFile =
new SourceFile(_('/foo/src/index.js'), 'index contents', rawSourceMap, false, []);
expect(sourceFile.flattenedMappings).toEqual([]);
});
it('should be the same as non-flat mappings if there is only one level of source map',
() => {
const rawSourceMap: RawSourceMap = {
mappings: encode([[[0, 0, 0, 0], [6, 0, 0, 3]]]),
names: [],
sources: ['a.js'],
version: 3
};
const originalSource = new SourceFile(_('/foo/src/a.js'), 'abcdefg', null, false, []);
const sourceFile = new SourceFile(
_('/foo/src/index.js'), 'abc123defg', rawSourceMap, false, [originalSource]);
expect(removeOriginalSegmentLinks(sourceFile.flattenedMappings))
.toEqual(parseMappings(rawSourceMap, [originalSource], [0, 11]));
});
it('should merge mappings from flattened original source files', () => {
const cSource = new SourceFile(_('/foo/src/c.js'), 'bcd123', null, false, []);
const dSource = new SourceFile(_('/foo/src/d.js'), 'aef', null, false, []);
const bSourceMap: RawSourceMap = {
mappings: encode([[[0, 1, 0, 0], [1, 0, 0, 0], [4, 1, 0, 1]]]),
names: [],
sources: ['c.js', 'd.js'],
version: 3
};
const bSource =
new SourceFile(_('/foo/src/b.js'), 'abcdef', bSourceMap, false, [cSource, dSource]);
const aSourceMap: RawSourceMap = {
mappings: encode([[[0, 0, 0, 0], [2, 0, 0, 3], [4, 0, 0, 2], [5, 0, 0, 5]]]),
names: [],
sources: ['b.js'],
version: 3
};
const aSource =
new SourceFile(_('/foo/src/a.js'), 'abdecf', aSourceMap, false, [bSource]);
expect(removeOriginalSegmentLinks(aSource.flattenedMappings)).toEqual([
{
generatedSegment: {line: 0, column: 0, position: 0, next: undefined},
originalSource: dSource,
originalSegment: {line: 0, column: 0, position: 0, next: undefined},
name: undefined
},
{
generatedSegment: {line: 0, column: 1, position: 1, next: undefined},
originalSource: cSource,
originalSegment: {line: 0, column: 0, position: 0, next: undefined},
name: undefined
},
{
generatedSegment: {line: 0, column: 2, position: 2, next: undefined},
originalSource: cSource,
originalSegment: {line: 0, column: 2, position: 2, next: undefined},
name: undefined
},
{
generatedSegment: {line: 0, column: 3, position: 3, next: undefined},
originalSource: dSource,
originalSegment: {line: 0, column: 1, position: 1, next: undefined},
name: undefined
},
{
generatedSegment: {line: 0, column: 4, position: 4, next: undefined},
originalSource: cSource,
originalSegment: {line: 0, column: 1, position: 1, next: undefined},
name: undefined
},
{
generatedSegment: {line: 0, column: 5, position: 5, next: undefined},
originalSource: dSource,
originalSegment: {line: 0, column: 2, position: 2, next: undefined},
name: undefined
},
]);
});
it('should ignore mappings to missing source files', () => {
const bSourceMap: RawSourceMap = {
mappings: encode([[[1, 0, 0, 0], [4, 0, 0, 3], [4, 0, 0, 6], [5, 0, 0, 7]]]),
names: [],
sources: ['c.js'],
version: 3
};
const bSource = new SourceFile(_('/foo/src/b.js'), 'abcdef', bSourceMap, false, [null]);
const aSourceMap: RawSourceMap = {
mappings: encode([[[0, 0, 0, 0], [2, 0, 0, 3], [4, 0, 0, 2], [5, 0, 0, 5]]]),
names: [],
sources: ['b.js'],
version: 3
};
const aSource =
new SourceFile(_('/foo/src/a.js'), 'abdecf', aSourceMap, false, [bSource]);
// These flattened mappings are just the mappings from a to b.
// (The mappings to c are dropped since there is no source file to map to.)
expect(removeOriginalSegmentLinks(aSource.flattenedMappings))
.toEqual(parseMappings(aSourceMap, [bSource], [0, 7]));
});
/**
* Clean out the links between original segments of each of the given `mappings`.
*
* @param mappings the mappings whose segments are to be cleaned.
*/
function removeOriginalSegmentLinks(mappings: Mapping[]) {
for (const mapping of mappings) {
mapping.originalSegment.next = undefined;
}
return mappings;
}
});
describe('renderFlattenedSourceMap()', () => {
it('should convert the flattenedMappings into a raw source-map object', () => {
const cSource = new SourceFile(_('/foo/src/c.js'), 'bcd123e', null, false, []);
const bToCSourceMap: RawSourceMap = {
mappings: encode([[[1, 0, 0, 0], [4, 0, 0, 3], [4, 0, 0, 6], [5, 0, 0, 7]]]),
names: [],
sources: ['c.js'],
version: 3
};
const bSource =
new SourceFile(_('/foo/src/b.js'), 'abcdef', bToCSourceMap, false, [cSource]);
const aToBSourceMap: RawSourceMap = {
mappings: encode([[[0, 0, 0, 0], [2, 0, 0, 3], [4, 0, 0, 2], [5, 0, 0, 5]]]),
names: [],
sources: ['b.js'],
version: 3
};
const aSource =
new SourceFile(_('/foo/src/a.js'), 'abdecf', aToBSourceMap, false, [bSource]);
const aTocSourceMap = aSource.renderFlattenedSourceMap();
expect(aTocSourceMap.version).toEqual(3);
expect(aTocSourceMap.file).toEqual('a.js');
expect(aTocSourceMap.names).toEqual([]);
expect(aTocSourceMap.sourceRoot).toBeUndefined();
expect(aTocSourceMap.sources).toEqual(['c.js']);
expect(aTocSourceMap.sourcesContent).toEqual(['bcd123e']);
expect(aTocSourceMap.mappings).toEqual(encode([
[[1, 0, 0, 0], [2, 0, 0, 2], [3, 0, 0, 3], [3, 0, 0, 6], [4, 0, 0, 1], [5, 0, 0, 7]]
]));
});
it('should handle mappings that map from lines outside of the actual content lines', () => {
const bSource = new SourceFile(_('/foo/src/b.js'), 'abcdef', null, false, []);
const aToBSourceMap: RawSourceMap = {
mappings: encode([
[[0, 0, 0, 0], [2, 0, 0, 3], [4, 0, 0, 2], [5, 0, 0, 5]],
[
[0, 0, 0, 0], // Extra mapping from a non-existent line
]
]),
names: [],
sources: ['b.js'],
version: 3
};
const aSource =
new SourceFile(_('/foo/src/a.js'), 'abdecf', aToBSourceMap, false, [bSource]);
const aTocSourceMap = aSource.renderFlattenedSourceMap();
expect(aTocSourceMap.version).toEqual(3);
expect(aTocSourceMap.file).toEqual('a.js');
expect(aTocSourceMap.names).toEqual([]);
expect(aTocSourceMap.sourceRoot).toBeUndefined();
expect(aTocSourceMap.sources).toEqual(['b.js']);
expect(aTocSourceMap.sourcesContent).toEqual(['abcdef']);
expect(aTocSourceMap.mappings).toEqual(aToBSourceMap.mappings);
});
});
});
describe('computeStartOfLinePositions()', () => {
it('should compute the cumulative length of each line in the given string', () => {
expect(computeStartOfLinePositions('')).toEqual([0]);
expect(computeStartOfLinePositions('abc')).toEqual([0]);
expect(computeStartOfLinePositions('\n')).toEqual([0, 1]);
expect(computeStartOfLinePositions('\n\n')).toEqual([0, 1, 2]);
expect(computeStartOfLinePositions('abc\n')).toEqual([0, 4]);
expect(computeStartOfLinePositions('\nabc')).toEqual([0, 1]);
expect(computeStartOfLinePositions('abc\ndefg')).toEqual([0, 4]);
expect(computeStartOfLinePositions('abc\r\n')).toEqual([0, 4]);
expect(computeStartOfLinePositions('abc\r\ndefg')).toEqual([0, 4]);
});
});
});
});