GoScrobble/web/node_modules/v8-to-istanbul/lib/source.js

248 lines
7.7 KiB
JavaScript

const CovLine = require('./line')
const { GREATEST_LOWER_BOUND, LEAST_UPPER_BOUND } = require('source-map').SourceMapConsumer
module.exports = class CovSource {
constructor (sourceRaw, wrapperLength) {
sourceRaw = sourceRaw.trimEnd()
this.lines = []
this.eof = sourceRaw.length
this.shebangLength = getShebangLength(sourceRaw)
this.wrapperLength = wrapperLength - this.shebangLength
this._buildLines(sourceRaw)
}
_buildLines (source) {
let position = 0
let ignoreCount = 0
let ignoreAll = false
for (const [i, lineStr] of source.split(/(?<=\r?\n)/u).entries()) {
const line = new CovLine(i + 1, position, lineStr)
if (ignoreCount > 0) {
line.ignore = true
ignoreCount--
} else if (ignoreAll) {
line.ignore = true
}
this.lines.push(line)
position += lineStr.length
const ignoreToken = this._parseIgnore(lineStr)
if (!ignoreToken) continue
line.ignore = true
if (ignoreToken.count !== undefined) {
ignoreCount = ignoreToken.count
}
if (ignoreToken.start || ignoreToken.stop) {
ignoreAll = ignoreToken.start
ignoreCount = 0
}
}
}
/**
* Parses for comments:
* c8 ignore next
* c8 ignore next 3
* c8 ignore start
* c8 ignore stop
* @param {string} lineStr
* @return {{count?: number, start?: boolean, stop?: boolean}|undefined}
*/
_parseIgnore (lineStr) {
const testIgnoreNextLines = lineStr.match(/^\W*\/\* c8 ignore next (?<count>[0-9]+) *\*\/\W*$/)
if (testIgnoreNextLines) {
return { count: Number(testIgnoreNextLines.groups.count) }
}
// Check if comment is on its own line.
if (lineStr.match(/^\W*\/\* c8 ignore next *\*\/\W*$/)) {
return { count: 1 }
}
if (lineStr.match(/\/\* c8 ignore next \*\//)) {
// Won't ignore successive lines, but the current line will be ignored.
return { count: 0 }
}
const testIgnoreStartStop = lineStr.match(/\/\* c8 ignore (?<mode>start|stop) *\*\//)
if (testIgnoreStartStop) {
if (testIgnoreStartStop.groups.mode === 'start') return { start: true }
if (testIgnoreStartStop.groups.mode === 'stop') return { stop: true }
}
}
// given a start column and end column in absolute offsets within
// a source file (0 - EOF), returns the relative line column positions.
offsetToOriginalRelative (sourceMap, startCol, endCol) {
const lines = this.lines.filter((line, i) => {
return startCol <= line.endCol && endCol >= line.startCol
})
if (!lines.length) return {}
const start = originalPositionTryBoth(
sourceMap,
lines[0].line,
Math.max(0, startCol - lines[0].startCol)
)
let end = originalEndPositionFor(
sourceMap,
lines[lines.length - 1].line,
endCol - lines[lines.length - 1].startCol
)
if (!(start && end)) {
return {}
}
if (!(start.source && end.source)) {
return {}
}
if (start.source !== end.source) {
return {}
}
if (start.line === end.line && start.column === end.column) {
end = sourceMap.originalPositionFor({
line: lines[lines.length - 1].line,
column: endCol - lines[lines.length - 1].startCol,
bias: LEAST_UPPER_BOUND
})
end.column -= 1
}
return {
source: start.source,
startLine: start.line,
relStartCol: start.column,
endLine: end.line,
relEndCol: end.column
}
}
relativeToOffset (line, relCol) {
line = Math.max(line, 1)
if (this.lines[line - 1] === undefined) return this.eof
return Math.min(this.lines[line - 1].startCol + relCol, this.lines[line - 1].endCol)
}
}
// this implementation is pulled over from istanbul-lib-sourcemap:
// https://github.com/istanbuljs/istanbuljs/blob/master/packages/istanbul-lib-source-maps/lib/get-mapping.js
//
/**
* AST ranges are inclusive for start positions and exclusive for end positions.
* Source maps are also logically ranges over text, though interacting with
* them is generally achieved by working with explicit positions.
*
* When finding the _end_ location of an AST item, the range behavior is
* important because what we're asking for is the _end_ of whatever range
* corresponds to the end location we seek.
*
* This boils down to the following steps, conceptually, though the source-map
* library doesn't expose primitives to do this nicely:
*
* 1. Find the range on the generated file that ends at, or exclusively
* contains the end position of the AST node.
* 2. Find the range on the original file that corresponds to
* that generated range.
* 3. Find the _end_ location of that original range.
*/
function originalEndPositionFor (sourceMap, line, column) {
// Given the generated location, find the original location of the mapping
// that corresponds to a range on the generated file that overlaps the
// generated file end location. Note however that this position on its
// own is not useful because it is the position of the _start_ of the range
// on the original file, and we want the _end_ of the range.
const beforeEndMapping = originalPositionTryBoth(
sourceMap,
line,
Math.max(column - 1, 1)
)
if (beforeEndMapping.source === null) {
return null
}
// Convert that original position back to a generated one, with a bump
// to the right, and a rightward bias. Since 'generatedPositionFor' searches
// for mappings in the original-order sorted list, this will find the
// mapping that corresponds to the one immediately after the
// beforeEndMapping mapping.
const afterEndMapping = sourceMap.generatedPositionFor({
source: beforeEndMapping.source,
line: beforeEndMapping.line,
column: beforeEndMapping.column + 1,
bias: LEAST_UPPER_BOUND
})
if (
// If this is null, it means that we've hit the end of the file,
// so we can use Infinity as the end column.
afterEndMapping.line === null ||
// If these don't match, it means that the call to
// 'generatedPositionFor' didn't find any other original mappings on
// the line we gave, so consider the binding to extend to infinity.
sourceMap.originalPositionFor(afterEndMapping).line !==
beforeEndMapping.line
) {
return {
source: beforeEndMapping.source,
line: beforeEndMapping.line,
column: Infinity
}
}
// Convert the end mapping into the real original position.
return sourceMap.originalPositionFor(afterEndMapping)
}
function originalPositionTryBoth (sourceMap, line, column) {
let original = sourceMap.originalPositionFor({
line,
column,
bias: GREATEST_LOWER_BOUND
})
if (original.line === null) {
original = sourceMap.originalPositionFor({
line,
column,
bias: LEAST_UPPER_BOUND
})
}
// The source maps generated by https://github.com/istanbuljs/istanbuljs
// (using @babel/core 7.7.5) have behavior, such that a mapping
// mid-way through a line maps to an earlier line than a mapping
// at position 0. Using the line at positon 0 seems to provide better reports:
//
// if (true) {
// cov_y5divc6zu().b[1][0]++;
// cov_y5divc6zu().s[3]++;
// console.info('reachable');
// } else { ... }
// ^ ^
// l5 l3
const min = sourceMap.originalPositionFor({
line,
column: 0,
bias: GREATEST_LOWER_BOUND
})
if (min.line > original.line) {
original = min
}
return original
}
// Not required since Node 12, see: https://github.com/nodejs/node/pull/27375
const isPreNode12 = /^v1[0-1]\./u.test(process.version)
function getShebangLength (source) {
if (isPreNode12 && source.indexOf('#!') === 0) {
const match = source.match(/(?<shebang>#!.*)/)
if (match) {
return match.groups.shebang.length
}
} else {
return 0
}
}