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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 {
setBreakpointAtEntryPoints,
const {
getSourcemapBaseURL,
const {
getDebuggerSourceURL,
loader.lazyRequireGetter(
this,
"ArrayBufferActor",
true
);
loader.lazyRequireGetter(
this,
"LongStringActor",
true
);
loader.lazyRequireGetter(
this,
"DevToolsUtils",
);
const windowsDrive = /^([a-zA-Z]:)/;
function resolveSourceURL(sourceURL, targetActor) {
if (sourceURL) {
try {
let baseURL;
if (targetActor.window) {
baseURL = targetActor.window.location?.href;
}
// For worker, we don't have easy access to location,
// so pull extra information directly from the target actor.
if (targetActor.workerUrl) {
baseURL = targetActor.workerUrl;
}
return new URL(sourceURL, baseURL || undefined).href;
} catch (err) {}
}
return null;
}
function getSourceURL(source, targetActor) {
// Some eval sources have URLs, but we want to explicitly ignore those because
// they are generally useless strings like "eval" or "debugger eval code".
let resourceURL = getDebuggerSourceURL(source) || "";
// Strip out eventual stack trace stored in Source's url.
// (not clear if that still happens)
resourceURL = resourceURL.split(" -> ").pop();
// Debugger.Source.url attribute may be of the form:
// because of the following function `js::FormatIntroducedFilename`:
// This isn't so easy to reproduce, but browser_dbg-breakpoints-popup.js's testPausedInTwoPopups covers this
resourceURL = resourceURL.replace(/ line \d+ > .*$/, "");
// A "//# sourceURL=" pragma should basically be treated as a source file's
// full URL, so that is what we want to use as the base if it is present.
// If this is not an absolute URL, this will mean the maps in the file
// will not have a valid base URL, but that is up to tooling that
let result = resolveSourceURL(source.displayURL, targetActor);
if (!result) {
result = resolveSourceURL(resourceURL, targetActor) || resourceURL;
// In XPCShell tests, the source URL isn't actually a URL, it's a file path.
// That causes issues because "C:/folder/file.js" is parsed as a URL with
// "c:" as the URL scheme, which causes the drive letter to be unexpectedly
// lower-cased when the parsed URL is re-serialized. To avoid that, we
// detect that case and re-uppercase it again. This is a bit gross and
// ideally it seems like XPCShell tests should use file:// URLs for files,
// but alas they do not.
if (
resourceURL &&
resourceURL.match(windowsDrive) &&
result.slice(0, 2) == resourceURL.slice(0, 2).toLowerCase()
) {
result = resourceURL.slice(0, 2) + result.slice(2);
}
}
// Avoid returning empty string and return null if no URL is found
return result || null;
}
/**
* A SourceActor provides information about the source of a script. Source
* actors are 1:1 with Debugger.Source objects.
*
* @param Debugger.Source source
* The source object we are representing.
* @param ThreadActor thread
* The current thread actor.
*/
class SourceActor extends Actor {
constructor({ source, thread }) {
super(thread.conn, sourceSpec);
this._threadActor = thread;
this._url = undefined;
this._source = source;
this.__isInlineSource = undefined;
}
get _isInlineSource() {
const source = this._source;
if (this.__isInlineSource === undefined) {
// If the source has a usable displayURL, the source is treated as not
// inlined because it has its own URL.
// Also consider sources loaded from <iframe srcdoc> as independant sources,
// because we can't easily fetch the full html content of the srcdoc attribute.
this.__isInlineSource =
source.introductionType === "inlineScript" &&
!resolveSourceURL(source.displayURL, this.threadActor.targetActor) &&
!this.url.startsWith("about:srcdoc");
}
return this.__isInlineSource;
}
get threadActor() {
return this._threadActor;
}
get sourcesManager() {
return this._threadActor.sourcesManager;
}
get dbg() {
return this.threadActor.dbg;
}
get breakpointActorMap() {
return this.threadActor.breakpointActorMap;
}
get url() {
if (this._url === undefined) {
this._url = getSourceURL(this._source, this.threadActor.targetActor);
}
return this._url;
}
get extensionName() {
if (this._extensionName === undefined) {
this._extensionName = null;
// Cu is not available for workers and so we are not able to get a
// WebExtensionPolicy object
if (!isWorker && this.url?.startsWith("moz-extension:")) {
try {
const extURI = Services.io.newURI(this.url);
const policy = WebExtensionPolicy.getByURI(extURI);
if (policy) {
this._extensionName = policy.name;
}
} catch (e) {
console.warn(`Failed to find extension name for ${this.url} : ${e}`);
}
}
}
return this._extensionName;
}
get internalSourceId() {
return this._source.id;
}
form() {
const source = this._source;
let introductionType = source.introductionType;
if (
introductionType === "srcScript" ||
introductionType === "inlineScript" ||
introductionType === "injectedScript"
) {
// These three used to be one single type, so here we combine them all
// so that clients don't see any change in behavior.
introductionType = "scriptElement";
}
// NOTE: Debugger.Source.prototype.startColumn is 1-based.
// Convert to 0-based, while keeping the wasm's column (1) as is.
const columnBase = source.introductionType === "wasm" ? 0 : 1;
return {
actor: this.actorID,
extensionName: this.extensionName,
url: this.url,
isBlackBoxed: this.sourcesManager.isBlackBoxed(this.url),
sourceMapBaseURL: getSourcemapBaseURL(
this.url,
this.threadActor.targetActor.window
),
sourceMapURL: source.sourceMapURL,
introductionType,
isInlineSource: this._isInlineSource,
sourceStartLine: source.startLine,
sourceStartColumn: source.startColumn - columnBase,
sourceLength: source.text?.length,
};
}
destroy() {
const parent = this.getParent();
if (parent && parent.sourceActors) {
delete parent.sourceActors[this.actorID];
}
super.destroy();
}
get _isWasm() {
return this._source.introductionType === "wasm";
}
async _getSourceText() {
if (this._isWasm) {
const wasm = this._source.binary;
const buffer = wasm.buffer;
DevToolsUtils.assert(
wasm.byteOffset === 0 && wasm.byteLength === buffer.byteLength,
"Typed array from wasm source binary must cover entire buffer"
);
return {
content: buffer,
contentType: "text/wasm",
};
}
// Use `source.text` if it exists, is not the "no source" string, and
// the source isn't one that is inlined into some larger file.
// It will be "no source" if the Debugger API wasn't able to load
// the source because sources were discarded
// (javascript.options.discardSystemSource == true).
//
// For inline source, we do something special and ignore individual source content.
// Instead, each inline source will return the full HTML page content where
// the inline source is (i.e. `<script> js source </script>`).
//
// When using srcdoc attribute on iframes:
// <iframe srcdoc="<script> js source </script>"></iframe>
// The whole iframe source is going to be considered as an inline source because displayURL is null
// and introductionType is inlineScript. But Debugger.Source.text is the only way
// to retrieve the source content.
if (this._source.text !== "[no source]" && !this._isInlineSource) {
return {
content: this.actualText(),
contentType: "text/javascript",
};
}
return this.sourcesManager.urlContents(
this.url,
/* partial */ false,
/* canUseCache */ this._isInlineSource
);
}
// Get the actual text of this source, padded so that line numbers will match
// up with the source itself.
actualText() {
// If the source doesn't start at line 1, line numbers in the client will
// not match up with those in the source. Pad the text with blank lines to
// fix this. This can show up for sources associated with inline scripts
// in HTML created via document.write() calls: the script's source line
// number is relative to the start of the written HTML, but we show the
// source's content by itself.
const padding = this._source.startLine
? "\n".repeat(this._source.startLine - 1)
: "";
return padding + this._source.text;
}
// Return whether the specified fetched contents includes the actual text of
// this source in the expected position.
contentMatches(fileContents) {
const lineBreak = /\r\n?|\n|\u2028|\u2029/;
const contentLines = fileContents.content.split(lineBreak);
const sourceLines = this._source.text.split(lineBreak);
let line = this._source.startLine - 1;
for (const sourceLine of sourceLines) {
const contentLine = contentLines[line++] || "";
if (!contentLine.includes(sourceLine)) {
return false;
}
}
return true;
}
getBreakableLines() {
const positions = this._getBreakpointPositions();
const lines = new Set();
for (const position of positions) {
if (!lines.has(position.line)) {
lines.add(position.line);
}
}
return Array.from(lines);
}
// Get all toplevel scripts in the source. Transitive child scripts must be
// found by traversing the child script tree.
_getTopLevelDebuggeeScripts() {
if (this._scripts) {
return this._scripts;
}
let scripts = this.dbg.findScripts({ source: this._source });
if (!this._isWasm) {
// There is no easier way to get the top-level scripts right now, so
// we have to build that up the list manually.
// Note: It is not valid to simply look for scripts where
// `.isFunction == false` because a source may have executed multiple
const allScripts = new Set(scripts);
for (const script of allScripts) {
for (const child of script.getChildScripts()) {
allScripts.delete(child);
}
}
scripts = [...allScripts];
}
this._scripts = scripts;
return scripts;
}
resetDebuggeeScripts() {
this._scripts = null;
}
// Get toplevel scripts which contain all breakpoint positions for the source.
// This is different from _scripts if we detected that some scripts have been
// GC'ed and reparsed the source contents.
_getTopLevelBreakpointPositionScripts() {
if (this._breakpointPositionScripts) {
return this._breakpointPositionScripts;
}
let scripts = this._getTopLevelDebuggeeScripts();
// We need to find all breakpoint positions, even if scripts associated with
// this source have been GC'ed. We detect this by looking for a script which
// does not have a function: a source will typically have a top level
// non-function script. If this top level script still exists, then it keeps
// all its child scripts alive and we will find all breakpoint positions by
// scanning the existing scripts. If the top level script has been GC'ed
// then we won't find its breakpoint positions, and inner functions may have
// been GC'ed as well. In this case we reparse the source and generate a new
// and complete set of scripts to look for the breakpoint positions.
// Note that in some cases like "new Function(stuff)" there might not be a
// top level non-function script, but if there is a non-function script then
// it must be at the top level and will keep all other scripts in the source
// alive.
if (!this._isWasm && !scripts.some(script => !script.isFunction)) {
let newScript;
try {
newScript = this._source.reparse();
} catch (e) {
// reparse() will throw if the source is not valid JS. This can happen
// if this source is the resurrection of a GC'ed source and there are
// parse errors in the refetched contents.
}
if (newScript) {
scripts = [newScript];
}
}
this._breakpointPositionScripts = scripts;
return scripts;
}
// Get all scripts in this source that might include content in the range
// specified by the given query.
_findDebuggeeScripts(query, forBreakpointPositions) {
const scripts = forBreakpointPositions
? this._getTopLevelBreakpointPositionScripts()
: this._getTopLevelDebuggeeScripts();
const {
start: { line: startLine = 0, column: startColumn = 0 } = {},
end: { line: endLine = Infinity, column: endColumn = Infinity } = {},
} = query || {};
const rv = [];
addMatchingScripts(scripts);
return rv;
function scriptMatches(script) {
// These tests are approximate, as we can't easily get the script's end
// column.
let lineCount;
try {
lineCount = script.lineCount;
} catch (err) {
// Accessing scripts which were optimized out during parsing can throw
// an exception. Tolerate these so that we can still get positions for
// other scripts in the source.
return false;
}
// NOTE: Debugger.Script.prototype.startColumn is 1-based.
// Convert to 0-based, while keeping the wasm's column (1) as is.
const columnBase = script.format === "wasm" ? 0 : 1;
if (
script.startLine > endLine ||
script.startLine + lineCount <= startLine ||
(script.startLine == endLine &&
script.startColumn - columnBase > endColumn)
) {
return false;
}
if (
lineCount == 1 &&
script.startLine == startLine &&
script.startColumn - columnBase + script.sourceLength <= startColumn
) {
return false;
}
return true;
}
function addMatchingScripts(childScripts) {
for (const script of childScripts) {
if (scriptMatches(script)) {
rv.push(script);
if (script.format === "js") {
addMatchingScripts(script.getChildScripts());
}
}
}
}
}
_getBreakpointPositions(query) {
const scripts = this._findDebuggeeScripts(
query,
/* forBreakpointPositions */ true
);
const positions = [];
for (const script of scripts) {
this._addScriptBreakpointPositions(query, script, positions);
}
return (
positions
// Sort the items by location.
.sort((a, b) => {
const lineDiff = a.line - b.line;
return lineDiff === 0 ? a.column - b.column : lineDiff;
})
);
}
_addScriptBreakpointPositions(query, script, positions) {
const {
start: { line: startLine = 0, column: startColumn = 0 } = {},
end: { line: endLine = Infinity, column: endColumn = Infinity } = {},
} = query || {};
// NOTE: Debugger.Script.prototype.startColumn is 1-based.
// Convert to 0-based, while keeping the wasm's column (1) as is.
const columnBase = script.format === "wasm" ? 0 : 1;
const offsets = script.getPossibleBreakpoints();
for (const { lineNumber, columnNumber } of offsets) {
if (
lineNumber < startLine ||
(lineNumber === startLine && columnNumber - columnBase < startColumn) ||
lineNumber > endLine ||
(lineNumber === endLine && columnNumber - columnBase >= endColumn)
) {
continue;
}
positions.push({
line: lineNumber,
column: columnNumber - columnBase,
});
}
}
getBreakpointPositionsCompressed(query) {
const items = this._getBreakpointPositions(query);
const compressed = {};
for (const { line, column } of items) {
if (!compressed[line]) {
compressed[line] = [];
}
compressed[line].push(column);
}
return compressed;
}
/**
* Handler for the "onSource" packet.
* @return Object
* The return of this function contains a field `contentType`, and
* a field `source`. `source` can either be an ArrayBuffer or
* a LongString.
*/
async source() {
try {
const { content, contentType } = await this._getSourceText();
if (
typeof content === "object" &&
content &&
content.constructor &&
content.constructor.name === "ArrayBuffer"
) {
return {
source: new ArrayBufferActor(this.threadActor.conn, content),
contentType,
};
}
return {
source: new LongStringActor(this.threadActor.conn, content),
contentType,
};
} catch (error) {
throw new Error(
"Could not load the source for " +
this.url +
".\n" +
DevToolsUtils.safeErrorString(error)
);
}
}
/**
* Handler for the "blackbox" packet.
*/
blackbox(range) {
this.sourcesManager.blackBox(this.url, range);
if (
this.threadActor.state == "paused" &&
this.threadActor.youngestFrame &&
this.threadActor.youngestFrame.script.url == this.url
) {
return true;
}
return false;
}
/**
* Handler for the "unblackbox" packet.
*/
unblackbox(range) {
this.sourcesManager.unblackBox(this.url, range);
}
/**
* Handler for the "setPausePoints" packet.
*
* @param Array pausePoints
* A dictionary of pausePoint objects
*
* type PausePoints = {
* line: {
* column: { break?: boolean, step?: boolean }
* }
* }
*/
setPausePoints(pausePoints) {
const uncompressed = {};
const points = {
0: {},
1: { break: true },
2: { step: true },
3: { break: true, step: true },
};
for (const line in pausePoints) {
uncompressed[line] = {};
for (const col in pausePoints[line]) {
uncompressed[line][col] = points[pausePoints[line][col]];
}
}
this.pausePoints = uncompressed;
}
/*
* Ensure the given BreakpointActor is set as a breakpoint handler on all
* scripts that match its location in the generated source.
*
* @param BreakpointActor actor
* The BreakpointActor to be set as a breakpoint handler.
*
* @returns A Promise that resolves to the given BreakpointActor.
*/
async applyBreakpoint(actor) {
const { line, column } = actor.location;
// Find all entry points that correspond to the given location.
const entryPoints = [];
if (column === undefined) {
// Find all scripts that match the given source actor and line
// number.
const query = { start: { line }, end: { line } };
const scripts = this._findDebuggeeScripts(query).filter(
script => !actor.hasScript(script)
);
// NOTE: Debugger.Script.prototype.getPossibleBreakpoints returns
// columnNumber in 1-based.
// The following code uses columnNumber only for comparing against
// other columnNumber, and we don't need to convert to 0-based.
// This is a line breakpoint, so we add a breakpoint on the first
// breakpoint on the line.
const lineMatches = [];
for (const script of scripts) {
const possibleBreakpoints = script.getPossibleBreakpoints({ line });
for (const possibleBreakpoint of possibleBreakpoints) {
lineMatches.push({ ...possibleBreakpoint, script });
}
}
lineMatches.sort((a, b) => a.columnNumber - b.columnNumber);
if (lineMatches.length) {
// A single Debugger.Source may have _multiple_ Debugger.Scripts
// at the same position from multiple evaluations of the source,
// so we explicitly want to take all of the matches for the matched
// column number.
const firstColumn = lineMatches[0].columnNumber;
const firstColumnMatches = lineMatches.filter(
m => m.columnNumber === firstColumn
);
for (const { script, offset } of firstColumnMatches) {
entryPoints.push({ script, offsets: [offset] });
}
}
} else {
// Find all scripts that match the given source actor, line,
// and column number.
const query = { start: { line, column }, end: { line, column } };
const scripts = this._findDebuggeeScripts(query).filter(
script => !actor.hasScript(script)
);
for (const script of scripts) {
// NOTE: getPossibleBreakpoints's minColumn/maxColumn parameters are
// 1-based.
// Convert to 1-based, while keeping the wasm's column (1) as is.
const columnBase = script.format === "wasm" ? 0 : 1;
// Check to see if the script contains a breakpoint position at
// this line and column.
const possibleBreakpoint = script
.getPossibleBreakpoints({
line,
minColumn: column + columnBase,
maxColumn: column + columnBase + 1,
})
.pop();
if (possibleBreakpoint) {
const { offset } = possibleBreakpoint;
entryPoints.push({ script, offsets: [offset] });
}
}
}
setBreakpointAtEntryPoints(actor, entryPoints);
}
}
exports.SourceActor = SourceActor;