tenebrous-dicebot/api/node_modules/webpack-sources/lib/applySourceMap.js

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/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const SourceNode = require("source-map").SourceNode;
const SourceMapConsumer = require("source-map").SourceMapConsumer;
const applySourceMap = function (
sourceNode,
sourceMapConsumer,
sourceFile,
removeGeneratedCodeForSourceFile
) {
// The following notations are used to name stuff:
// Left <------------> Middle <-------------------> Right
// Input arguments:
// sourceNode - Code mapping from Left to Middle
// sourceFile - Name of a Middle file
// sourceMapConsumer - Code mapping from Middle to Right
// Variables:
// l2m m2r
// Left <-----------------------------------------> Right
// Variables:
// l2r
const l2rResult = new SourceNode();
const l2rOutput = [];
const middleSourceContents = {};
const m2rMappingsByLine = {};
const rightSourceContentsSet = {};
const rightSourceContentsLines = {};
// Store all mappings by generated line
sourceMapConsumer.eachMapping(
function (mapping) {
(m2rMappingsByLine[mapping.generatedLine] =
m2rMappingsByLine[mapping.generatedLine] || []).push(mapping);
},
null,
SourceMapConsumer.GENERATED_ORDER
);
const findM2rMapping = (line, column) => {
const m2rMappings = m2rMappingsByLine[line];
let l = 0;
let r = m2rMappings.length;
while (l < r) {
let m = (l + r) >> 1;
if (m2rMappings[m].generatedColumn <= column) {
l = m + 1;
} else {
r = m;
}
}
if (l === 0) return undefined;
return m2rMappings[l - 1];
};
// Store all source contents
sourceNode.walkSourceContents(function (source, content) {
middleSourceContents["$" + source] = content;
});
const middleSource = middleSourceContents["$" + sourceFile];
const middleSourceLines = middleSource ? middleSource.split("\n") : undefined;
// Walk all left to middle mappings
sourceNode.walk(function (chunk, middleMapping) {
// Find a mapping from middle to right
if (
middleMapping.source === sourceFile &&
middleMapping.line &&
m2rMappingsByLine[middleMapping.line]
) {
// For minimized sources this is performance-relevant,
// since all mappings are in a single line, use a binary search
let m2rBestFit = findM2rMapping(middleMapping.line, middleMapping.column);
if (m2rBestFit) {
let allowMiddleName = false;
let middleLine;
let rightSourceContent;
let rightSourceContentLines;
const rightSource = m2rBestFit.source;
// Check if we have middle and right source for this mapping
// Then we could have an "identify" mapping
if (
middleSourceLines &&
rightSource &&
(middleLine = middleSourceLines[m2rBestFit.generatedLine - 1]) &&
((rightSourceContentLines = rightSourceContentsLines[rightSource]) ||
(rightSourceContent = sourceMapConsumer.sourceContentFor(
rightSource,
true
)))
) {
if (!rightSourceContentLines) {
rightSourceContentLines = rightSourceContentsLines[
rightSource
] = rightSourceContent.split("\n");
}
const rightLine =
rightSourceContentLines[m2rBestFit.originalLine - 1];
if (rightLine) {
const offset = middleMapping.column - m2rBestFit.generatedColumn;
if (offset > 0) {
const middlePart = middleLine.slice(
m2rBestFit.generatedColumn,
middleMapping.column
);
const rightPart = rightLine.slice(
m2rBestFit.originalColumn,
m2rBestFit.originalColumn + offset
);
if (middlePart === rightPart) {
// When original and generated code is equal we assume we have an "identity" mapping
// In this case we can offset the original position
m2rBestFit = Object.assign({}, m2rBestFit, {
originalColumn: m2rBestFit.originalColumn + offset,
generatedColumn: middleMapping.column,
name: undefined
});
}
}
if (!m2rBestFit.name && middleMapping.name) {
allowMiddleName =
rightLine.slice(
m2rBestFit.originalColumn,
m2rBestFit.originalColumn + middleMapping.name.length
) === middleMapping.name;
}
}
}
// Construct a left to right node from the found middle to right mapping
let source = m2rBestFit.source;
// Workaround for bug in source-map
// null sources are incorrectly normalized to "."
if (source && source !== ".") {
l2rOutput.push(
new SourceNode(
m2rBestFit.originalLine,
m2rBestFit.originalColumn,
source,
chunk,
allowMiddleName ? middleMapping.name : m2rBestFit.name
)
);
// Set the source contents once
if (!("$" + source in rightSourceContentsSet)) {
rightSourceContentsSet["$" + source] = true;
const sourceContent = sourceMapConsumer.sourceContentFor(
source,
true
);
if (sourceContent) {
l2rResult.setSourceContent(source, sourceContent);
}
}
return;
}
}
}
if (
(removeGeneratedCodeForSourceFile &&
middleMapping.source === sourceFile) ||
!middleMapping.source
) {
// Construct a left to middle node with only generated code
// Because user do not want mappings to middle sources
// Or this chunk has no mapping
l2rOutput.push(chunk);
return;
}
// Construct a left to middle node
const source = middleMapping.source;
l2rOutput.push(
new SourceNode(
middleMapping.line,
middleMapping.column,
source,
chunk,
middleMapping.name
)
);
if ("$" + source in middleSourceContents) {
if (!("$" + source in rightSourceContentsSet)) {
l2rResult.setSourceContent(source, middleSourceContents["$" + source]);
delete middleSourceContents["$" + source];
}
}
});
// Put output into the resulting SourceNode
l2rResult.add(l2rOutput);
return l2rResult;
};
module.exports = applySourceMap;