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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const {
networkRequest,
const {
SourceMapConsumer,
} = require("resource://devtools/client/shared/vendor/source-map/source-map.js");
const {
getSourceMap,
setSourceMap,
const {
WasmRemap,
const {
convertToJSON,
// URLs which have been seen in a completed source map request.
const originalURLs = new Set();
function clearOriginalURLs() {
originalURLs.clear();
}
function hasOriginalURL(url) {
return originalURLs.has(url);
}
function resolveSourceMapURL(source) {
let { sourceMapBaseURL, sourceMapURL } = source;
sourceMapBaseURL = sourceMapBaseURL || "";
sourceMapURL = sourceMapURL || "";
if (!sourceMapBaseURL) {
// If the source doesn't have a URL, don't resolve anything.
return { resolvedSourceMapURL: sourceMapURL, baseURL: sourceMapURL };
}
let resolvedString;
let baseURL;
// When the sourceMap is a data: URL, fall back to using the source's URL,
// if possible. We don't use `new URL` here because it will be _very_ slow
// for large inlined source-maps, and we don't actually need to parse them.
if (sourceMapURL.startsWith("data:")) {
resolvedString = sourceMapURL;
baseURL = sourceMapBaseURL;
} else {
resolvedString = new URL(
sourceMapURL,
// If the URL is a data: URL, the sourceMapURL needs to be absolute, so
// we might as well pass `undefined` to avoid parsing a potentially
// very large data: URL for no reason.
sourceMapBaseURL.startsWith("data:") ? undefined : sourceMapBaseURL
).toString();
baseURL = resolvedString;
}
return { resolvedSourceMapURL: resolvedString, baseURL };
}
async function _fetch(generatedSource, resolvedSourceMapURL, baseURL) {
let fetched = await networkRequest(resolvedSourceMapURL, {
loadFromCache: false,
// Blocking redirects on the sourceMappingUrl as its not easy to verify if the
// redirect protocol matches the supported ones.
allowRedirects: false,
sourceMapBaseURL: generatedSource.sourceMapBaseURL,
});
if (fetched.isDwarf) {
fetched = { content: await convertToJSON(fetched.content) };
}
// Create the source map and fix it up.
let map = await new SourceMapConsumer(fetched.content, baseURL);
if (generatedSource.isWasm) {
map = new WasmRemap(map);
// Check if experimental scope info exists.
if (fetched.content.includes("x-scopes")) {
const parsedJSON = JSON.parse(fetched.content);
map.xScopes = parsedJSON["x-scopes"];
}
}
// Extend the default map object with sourceMapBaseURL, used to check further
// network requests made for this sourcemap.
map.sourceMapBaseURL = generatedSource.sourceMapBaseURL;
if (map && map.sources) {
map.sources.forEach(url => originalURLs.add(url));
}
return map;
}
function fetchSourceMap(generatedSource, resolvedSourceMapURL, baseURL) {
const existingRequest = getSourceMap(generatedSource.id);
// If it has already been requested, return the request. Make sure
// to do this even if sourcemapping is turned off, because
// pretty-printing uses sourcemaps.
//
// An important behavior here is that if it's in the middle of
// requesting it, all subsequent calls will block on the initial
// request.
if (existingRequest) {
return existingRequest;
}
if (!generatedSource.sourceMapURL) {
return null;
}
// Fire off the request, set it in the cache, and return it.
const req = _fetch(generatedSource, resolvedSourceMapURL, baseURL);
// Make sure the cached promise does not reject, because we only
// want to report the error once.
setSourceMap(
generatedSource.id,
req.catch(() => null)
);
return req;
}
module.exports = {
fetchSourceMap,
hasOriginalURL,
clearOriginalURLs,
resolveSourceMapURL,
};