工作端小程序
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

505 lines
15 KiB

3 months ago
import { encode, decode } from '@jridgewell/sourcemap-codec';
import resolver from './resolve';
import maybeSort from './sort';
import buildBySources from './by-source';
import {
memoizedState,
memoizedBinarySearch,
upperBound,
lowerBound,
found as bsFound,
} from './binary-search';
import {
COLUMN,
SOURCES_INDEX,
SOURCE_LINE,
SOURCE_COLUMN,
NAMES_INDEX,
REV_GENERATED_LINE,
REV_GENERATED_COLUMN,
} from './sourcemap-segment';
import { parse } from './types';
import type { SourceMapSegment, ReverseSegment } from './sourcemap-segment';
import type {
SourceMapV3,
DecodedSourceMap,
EncodedSourceMap,
InvalidOriginalMapping,
OriginalMapping,
InvalidGeneratedMapping,
GeneratedMapping,
SourceMapInput,
Needle,
SourceNeedle,
SourceMap,
EachMapping,
Bias,
XInput,
SectionedSourceMap,
Ro,
} from './types';
import type { Source } from './by-source';
import type { MemoState } from './binary-search';
export type { SourceMapSegment } from './sourcemap-segment';
export type {
SourceMap,
DecodedSourceMap,
EncodedSourceMap,
Section,
SectionedSourceMap,
SourceMapV3,
Bias,
EachMapping,
GeneratedMapping,
InvalidGeneratedMapping,
InvalidOriginalMapping,
Needle,
OriginalMapping,
OriginalMapping as Mapping,
SectionedSourceMapInput,
SourceMapInput,
SourceNeedle,
XInput,
EncodedSourceMapXInput,
DecodedSourceMapXInput,
SectionedSourceMapXInput,
SectionXInput,
} from './types';
interface PublicMap {
_encoded: TraceMap['_encoded'];
_decoded: TraceMap['_decoded'];
_decodedMemo: TraceMap['_decodedMemo'];
_bySources: TraceMap['_bySources'];
_bySourceMemos: TraceMap['_bySourceMemos'];
}
const LINE_GTR_ZERO = '`line` must be greater than 0 (lines start at line 1)';
const COL_GTR_EQ_ZERO = '`column` must be greater than or equal to 0 (columns start at column 0)';
export const LEAST_UPPER_BOUND = -1;
export const GREATEST_LOWER_BOUND = 1;
export { FlattenMap, FlattenMap as AnyMap } from './flatten-map';
export class TraceMap implements SourceMap {
declare version: SourceMapV3['version'];
declare file: SourceMapV3['file'];
declare names: SourceMapV3['names'];
declare sourceRoot: SourceMapV3['sourceRoot'];
declare sources: SourceMapV3['sources'];
declare sourcesContent: SourceMapV3['sourcesContent'];
declare ignoreList: SourceMapV3['ignoreList'];
declare resolvedSources: string[];
declare private _encoded: string | undefined;
declare private _decoded: SourceMapSegment[][] | undefined;
declare private _decodedMemo: MemoState;
declare private _bySources: Source[] | undefined;
declare private _bySourceMemos: MemoState[] | undefined;
constructor(map: Ro<SourceMapInput>, mapUrl?: string | null) {
const isString = typeof map === 'string';
if (!isString && (map as unknown as { _decodedMemo: any })._decodedMemo) return map as TraceMap;
const parsed = parse(map as Exclude<SourceMapInput, TraceMap>);
const { version, file, names, sourceRoot, sources, sourcesContent } = parsed;
this.version = version;
this.file = file;
this.names = names || [];
this.sourceRoot = sourceRoot;
this.sources = sources;
this.sourcesContent = sourcesContent;
this.ignoreList = parsed.ignoreList || (parsed as XInput).x_google_ignoreList || undefined;
const resolve = resolver(mapUrl, sourceRoot);
this.resolvedSources = sources.map(resolve);
const { mappings } = parsed;
if (typeof mappings === 'string') {
this._encoded = mappings;
this._decoded = undefined;
} else if (Array.isArray(mappings)) {
this._encoded = undefined;
this._decoded = maybeSort(mappings, isString);
} else if ((parsed as unknown as SectionedSourceMap).sections) {
throw new Error(`TraceMap passed sectioned source map, please use FlattenMap export instead`);
} else {
throw new Error(`invalid source map: ${JSON.stringify(parsed)}`);
}
this._decodedMemo = memoizedState();
this._bySources = undefined;
this._bySourceMemos = undefined;
}
}
/**
* Typescript doesn't allow friend access to private fields, so this just casts the map into a type
* with public access modifiers.
*/
function cast(map: unknown): PublicMap {
return map as any;
}
/**
* Returns the encoded (VLQ string) form of the SourceMap's mappings field.
*/
export function encodedMappings(map: TraceMap): EncodedSourceMap['mappings'] {
return (cast(map)._encoded ??= encode(cast(map)._decoded!));
}
/**
* Returns the decoded (array of lines of segments) form of the SourceMap's mappings field.
*/
export function decodedMappings(map: TraceMap): Readonly<DecodedSourceMap['mappings']> {
return (cast(map)._decoded ||= decode(cast(map)._encoded!));
}
/**
* A low-level API to find the segment associated with a generated line/column (think, from a
* stack trace). Line and column here are 0-based, unlike `originalPositionFor`.
*/
export function traceSegment(
map: TraceMap,
line: number,
column: number,
): Readonly<SourceMapSegment> | null {
const decoded = decodedMappings(map);
// It's common for parent source maps to have pointers to lines that have no
// mapping (like a "//# sourceMappingURL=") at the end of the child file.
if (line >= decoded.length) return null;
const segments = decoded[line];
const index = traceSegmentInternal(
segments,
cast(map)._decodedMemo,
line,
column,
GREATEST_LOWER_BOUND,
);
return index === -1 ? null : segments[index];
}
/**
* A higher-level API to find the source/line/column associated with a generated line/column
* (think, from a stack trace). Line is 1-based, but column is 0-based, due to legacy behavior in
* `source-map` library.
*/
export function originalPositionFor(
map: TraceMap,
needle: Needle,
): OriginalMapping | InvalidOriginalMapping {
let { line, column, bias } = needle;
line--;
if (line < 0) throw new Error(LINE_GTR_ZERO);
if (column < 0) throw new Error(COL_GTR_EQ_ZERO);
const decoded = decodedMappings(map);
// It's common for parent source maps to have pointers to lines that have no
// mapping (like a "//# sourceMappingURL=") at the end of the child file.
if (line >= decoded.length) return OMapping(null, null, null, null);
const segments = decoded[line];
const index = traceSegmentInternal(
segments,
cast(map)._decodedMemo,
line,
column,
bias || GREATEST_LOWER_BOUND,
);
if (index === -1) return OMapping(null, null, null, null);
const segment = segments[index];
if (segment.length === 1) return OMapping(null, null, null, null);
const { names, resolvedSources } = map;
return OMapping(
resolvedSources[segment[SOURCES_INDEX]],
segment[SOURCE_LINE] + 1,
segment[SOURCE_COLUMN],
segment.length === 5 ? names[segment[NAMES_INDEX]] : null,
);
}
/**
* Finds the generated line/column position of the provided source/line/column source position.
*/
export function generatedPositionFor(
map: TraceMap,
needle: SourceNeedle,
): GeneratedMapping | InvalidGeneratedMapping {
const { source, line, column, bias } = needle;
return generatedPosition(map, source, line, column, bias || GREATEST_LOWER_BOUND, false);
}
/**
* Finds all generated line/column positions of the provided source/line/column source position.
*/
export function allGeneratedPositionsFor(map: TraceMap, needle: SourceNeedle): GeneratedMapping[] {
const { source, line, column, bias } = needle;
// SourceMapConsumer uses LEAST_UPPER_BOUND for some reason, so we follow suit.
return generatedPosition(map, source, line, column, bias || LEAST_UPPER_BOUND, true);
}
/**
* Iterates each mapping in generated position order.
*/
export function eachMapping(map: TraceMap, cb: (mapping: EachMapping) => void): void {
const decoded = decodedMappings(map);
const { names, resolvedSources } = map;
for (let i = 0; i < decoded.length; i++) {
const line = decoded[i];
for (let j = 0; j < line.length; j++) {
const seg = line[j];
const generatedLine = i + 1;
const generatedColumn = seg[0];
let source = null;
let originalLine = null;
let originalColumn = null;
let name = null;
if (seg.length !== 1) {
source = resolvedSources[seg[1]];
originalLine = seg[2] + 1;
originalColumn = seg[3];
}
if (seg.length === 5) name = names[seg[4]];
cb({
generatedLine,
generatedColumn,
source,
originalLine,
originalColumn,
name,
} as EachMapping);
}
}
}
function sourceIndex(map: TraceMap, source: string): number {
const { sources, resolvedSources } = map;
let index = sources.indexOf(source);
if (index === -1) index = resolvedSources.indexOf(source);
return index;
}
/**
* Retrieves the source content for a particular source, if its found. Returns null if not.
*/
export function sourceContentFor(map: TraceMap, source: string): string | null {
const { sourcesContent } = map;
if (sourcesContent == null) return null;
const index = sourceIndex(map, source);
return index === -1 ? null : sourcesContent[index];
}
/**
* Determines if the source is marked to ignore by the source map.
*/
export function isIgnored(map: TraceMap, source: string): boolean {
const { ignoreList } = map;
if (ignoreList == null) return false;
const index = sourceIndex(map, source);
return index === -1 ? false : ignoreList.includes(index);
}
/**
* A helper that skips sorting of the input map's mappings array, which can be expensive for larger
* maps.
*/
export function presortedDecodedMap(map: DecodedSourceMap, mapUrl?: string): TraceMap {
const tracer = new TraceMap(clone(map, []), mapUrl);
cast(tracer)._decoded = map.mappings;
return tracer;
}
/**
* Returns a sourcemap object (with decoded mappings) suitable for passing to a library that expects
* a sourcemap, or to JSON.stringify.
*/
export function decodedMap(
map: TraceMap,
): Omit<DecodedSourceMap, 'mappings'> & { mappings: readonly SourceMapSegment[][] } {
return clone(map, decodedMappings(map));
}
/**
* Returns a sourcemap object (with encoded mappings) suitable for passing to a library that expects
* a sourcemap, or to JSON.stringify.
*/
export function encodedMap(map: TraceMap): EncodedSourceMap {
return clone(map, encodedMappings(map));
}
function clone<T extends string | readonly SourceMapSegment[][]>(
map: TraceMap | DecodedSourceMap,
mappings: T,
): T extends string ? EncodedSourceMap : DecodedSourceMap {
return {
version: map.version,
file: map.file,
names: map.names,
sourceRoot: map.sourceRoot,
sources: map.sources,
sourcesContent: map.sourcesContent,
mappings,
ignoreList: map.ignoreList || (map as XInput).x_google_ignoreList,
} as any;
}
function OMapping(source: null, line: null, column: null, name: null): InvalidOriginalMapping;
function OMapping(
source: string,
line: number,
column: number,
name: string | null,
): OriginalMapping;
function OMapping(
source: string | null,
line: number | null,
column: number | null,
name: string | null,
): OriginalMapping | InvalidOriginalMapping {
return { source, line, column, name } as any;
}
function GMapping(line: null, column: null): InvalidGeneratedMapping;
function GMapping(line: number, column: number): GeneratedMapping;
function GMapping(
line: number | null,
column: number | null,
): GeneratedMapping | InvalidGeneratedMapping {
return { line, column } as any;
}
function traceSegmentInternal(
segments: SourceMapSegment[],
memo: MemoState,
line: number,
column: number,
bias: Bias,
): number;
function traceSegmentInternal(
segments: ReverseSegment[],
memo: MemoState,
line: number,
column: number,
bias: Bias,
): number;
function traceSegmentInternal(
segments: SourceMapSegment[] | ReverseSegment[],
memo: MemoState,
line: number,
column: number,
bias: Bias,
): number {
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 -1;
return index;
}
function sliceGeneratedPositions(
segments: ReverseSegment[],
memo: MemoState,
line: number,
column: number,
bias: Bias,
): GeneratedMapping[] {
let min = traceSegmentInternal(segments, memo, line, column, GREATEST_LOWER_BOUND);
// We ignored the bias when tracing the segment so that we're guarnateed to find the first (in
// insertion order) segment that matched. Even if we did respect the bias when tracing, we would
// still need to call `lowerBound()` to find the first segment, which is slower than just looking
// for the GREATEST_LOWER_BOUND to begin with. The only difference that matters for us is when the
// binary search didn't match, in which case GREATEST_LOWER_BOUND just needs to increment to
// match LEAST_UPPER_BOUND.
if (!bsFound && bias === LEAST_UPPER_BOUND) min++;
if (min === -1 || min === segments.length) return [];
// We may have found the segment that started at an earlier column. If this is the case, then we
// need to slice all generated segments that match _that_ column, because all such segments span
// to our desired column.
const matchedColumn = bsFound ? column : segments[min][COLUMN];
// The binary search is not guaranteed to find the lower bound when a match wasn't found.
if (!bsFound) min = lowerBound(segments, matchedColumn, min);
const max = upperBound(segments, matchedColumn, min);
const result = [];
for (; min <= max; min++) {
const segment = segments[min];
result.push(GMapping(segment[REV_GENERATED_LINE] + 1, segment[REV_GENERATED_COLUMN]));
}
return result;
}
function generatedPosition(
map: TraceMap,
source: string,
line: number,
column: number,
bias: Bias,
all: false,
): GeneratedMapping | InvalidGeneratedMapping;
function generatedPosition(
map: TraceMap,
source: string,
line: number,
column: number,
bias: Bias,
all: true,
): GeneratedMapping[];
function generatedPosition(
map: TraceMap,
source: string,
line: number,
column: number,
bias: Bias,
all: boolean,
): GeneratedMapping | InvalidGeneratedMapping | GeneratedMapping[] {
line--;
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 all ? [] : GMapping(null, null);
const generated = (cast(map)._bySources ||= buildBySources(
decodedMappings(map),
(cast(map)._bySourceMemos = sources.map(memoizedState)),
));
const segments = generated[sourceIndex][line];
if (segments == null) return all ? [] : GMapping(null, null);
const memo = cast(map)._bySourceMemos![sourceIndex];
if (all) return sliceGeneratedPositions(segments, memo, line, column, bias);
const index = traceSegmentInternal(segments, memo, line, column, bias);
if (index === -1) return GMapping(null, null);
const segment = segments[index];
return GMapping(segment[REV_GENERATED_LINE] + 1, segment[REV_GENERATED_COLUMN]);
}