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Add allGeneratedPositionsFor (#19)
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Re: #18
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@connor4312
connor4312 committed Oct 7, 2022
1 parent 0cef974 commit 3b33e6a
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Showing 2 changed files with 104 additions and 27 deletions.
104 changes: 77 additions & 27 deletions src/trace-mapping.ts
View file
Expand Up @@ -101,6 +101,14 @@ export let generatedPositionFor: (
needle: SourceNeedle,
) => GeneratedMapping | InvalidGeneratedMapping;

/**
* Finds all source/line/columns that correspond to the provided source position.
*/
export let allGeneratedPositionsFor: (
map: TraceMap,
needle: SourceNeedle,
) => GeneratedMapping[];

/**
* Iterates each mapping in generated position order.
*/
Expand Down Expand Up @@ -198,13 +206,15 @@ export class TraceMap implements SourceMap {
// mapping (like a "//# sourceMappingURL=") at the end of the child file.
if (line >= decoded.length) return null;

return traceSegmentInternal(
const index = traceSegmentInternal(
decoded[line],
map._decodedMemo,
line,
column,
GREATEST_LOWER_BOUND,
);

return index == null ? null : decoded[line][index];
};

originalPositionFor = (map, { line, column, bias }) => {
Expand All @@ -218,15 +228,17 @@ export class TraceMap implements SourceMap {
// mapping (like a "//# sourceMappingURL=") at the end of the child file.
if (line >= decoded.length) return OMapping(null, null, null, null);

const segment = traceSegmentInternal(
const index = traceSegmentInternal(
decoded[line],
map._decodedMemo,
line,
column,
bias || GREATEST_LOWER_BOUND,
);

if (segment == null) return OMapping(null, null, null, null);
if (index == null) return OMapping(null, null, null, null);

const segment = decoded[line][index];
if (segment.length == 1) return OMapping(null, null, null, null);

const { names, resolvedSources } = map;
Expand All @@ -238,35 +250,55 @@ export class TraceMap implements SourceMap {
);
};

generatedPositionFor = (map, { source, line, column, bias }) => {
allGeneratedPositionsFor = (map, { source, line, column }) => {
line--;
if (line < 0) throw new Error(LINE_GTR_ZERO);
if (column < 0) throw new Error(COL_GTR_EQ_ZERO);
const components = getNeedleComponents(map, source, line, column);
if (components == null) return [];

const { sources, resolvedSources } = map;
let sourceIndex = sources.indexOf(source);
if (sourceIndex === -1) sourceIndex = resolvedSources.indexOf(source);
if (sourceIndex === -1) return GMapping(null, null);
let min = traceSegmentInternal(
components.segments,
components.memo,
line,
column,
GREATEST_LOWER_BOUND,
);
const max = traceSegmentInternal(
components.segments,
components.memo,
line,
column,
LEAST_UPPER_BOUND,
);

const generated = (map._bySources ||= buildBySources(
decodedMappings(map),
(map._bySourceMemos = sources.map(memoizedState)),
));
const memos = map._bySourceMemos!;
if (min == null || max == null) {
return [];
}

const segments = generated[sourceIndex][line];
const result = [];
for (; min <= max; min++) {
const segment = components.segments[min];
result.push(GMapping(segment[REV_GENERATED_LINE] + 1, segment[REV_GENERATED_COLUMN]));
}

return result;
};

if (segments == null) return GMapping(null, null);
generatedPositionFor = (map, { source, line, column, bias }) => {
line--;
const components = getNeedleComponents(map, source, line, column);
if (components == null) return GMapping(null, null);

const segment = traceSegmentInternal(
segments,
memos[sourceIndex],
const index = traceSegmentInternal(
components.segments,
components.memo,
line,
column,
bias || GREATEST_LOWER_BOUND,
);

if (segment == null) return GMapping(null, null);
if (index == null) return GMapping(null, null);

const segment = components.segments[index];
return GMapping(segment[REV_GENERATED_LINE] + 1, segment[REV_GENERATED_COLUMN]);
};

Expand Down Expand Up @@ -327,6 +359,24 @@ export class TraceMap implements SourceMap {
encodedMap = (map) => {
return clone(map, encodedMappings(map));
};

function getNeedleComponents(map: TraceMap, source: string, line: number, column: number) {
if (line < 0) throw new Error(LINE_GTR_ZERO);
if (column < 0) throw new Error(COL_GTR_EQ_ZERO);

const { sources, resolvedSources } = map;
let sourceIndex = sources.indexOf(source);
if (sourceIndex === -1) sourceIndex = resolvedSources.indexOf(source);
if (sourceIndex === -1) return null;

const generated = (map._bySources ||= buildBySources(
decodedMappings(map),
(map._bySourceMemos = sources.map(memoizedState)),
));
const memo = map._bySourceMemos![sourceIndex];
const segments = generated[sourceIndex][line];
return segments ? { memo, segments } : null;
}
}
}

Expand Down Expand Up @@ -366,8 +416,8 @@ function OMapping(
return { source, line, column, name } as any;
}

function GMapping(line: null, column: null): GeneratedMapping | InvalidGeneratedMapping;
function GMapping(line: number, column: number): GeneratedMapping | InvalidGeneratedMapping;
function GMapping(line: null, column: null): InvalidGeneratedMapping;
function GMapping(line: number, column: number): GeneratedMapping;
function GMapping(
line: number | null,
column: number | null,
Expand All @@ -381,26 +431,26 @@ function traceSegmentInternal(
line: number,
column: number,
bias: typeof LEAST_UPPER_BOUND | typeof GREATEST_LOWER_BOUND,
): Readonly<SourceMapSegment> | null;
): number | null;
function traceSegmentInternal(
segments: ReverseSegment[],
memo: MemoState,
line: number,
column: number,
bias: typeof LEAST_UPPER_BOUND | typeof GREATEST_LOWER_BOUND,
): Readonly<ReverseSegment> | null;
): number | null;
function traceSegmentInternal(
segments: SourceMapSegment[] | ReverseSegment[],
memo: MemoState,
line: number,
column: number,
bias: typeof LEAST_UPPER_BOUND | typeof GREATEST_LOWER_BOUND,
): Readonly<SourceMapSegment | ReverseSegment> | null {
): number | null {
let index = memoizedBinarySearch(segments, column, memo, line);
if (bsFound) {
index = (bias === LEAST_UPPER_BOUND ? upperBound : lowerBound)(segments, column, index);
} else if (bias === LEAST_UPPER_BOUND) index++;

if (index === -1 || index === segments.length) return null;
return segments[index];
return index;
}
27 changes: 27 additions & 0 deletions test/trace-mapping.test.ts
View file
Expand Up @@ -15,6 +15,7 @@ import {
eachMapping,
GREATEST_LOWER_BOUND,
LEAST_UPPER_BOUND,
allGeneratedPositionsFor,
} from '../src/trace-mapping';

import type { ExecutionContext } from 'ava';
Expand Down Expand Up @@ -300,6 +301,32 @@ describe('TraceMap', () => {
column: 0,
});
});

test('allGeneratedPositionsFor', (t) => {
const tracer = new TraceMap(map);

t.deepEqual(
allGeneratedPositionsFor(tracer, {
source: 'input.js',
line: 1,
column: 14,
}),
[
{
line: 1,
column: 13,
},
{
line: 1,
column: 18,
},
],
);


t.deepEqual(allGeneratedPositionsFor(tracer, { source: 'input.js', line: 100, column: 13 }), []);
t.deepEqual(allGeneratedPositionsFor(tracer, { source: 'input.js', line: 1, column: 100 }), []);
});
};
}

Expand Down

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