From 6b951458405a806aa5a6bed4f585fc84e6d5feb5 Mon Sep 17 00:00:00 2001
From: David Michon <dmichon@microsoft.com>
Date: Wed, 8 Jan 2025 23:17:28 +0000
Subject: [PATCH 1/2] feat: Use single-linked list for resolver stack
---
lib/Resolver.js | 117 +++++++++++++++++++++++++++++++++++-------------
types.d.ts | 12 ++++-
2 files changed, 97 insertions(+), 32 deletions(-)
diff --git a/lib/Resolver.js b/lib/Resolver.js
index fdb73dc..6315663 100644
--- a/lib/Resolver.js
+++ b/lib/Resolver.js
@@ -306,8 +306,16 @@ const {
/** @typedef {BaseResolveRequest & Partial<ParsedIdentifier>} ResolveRequest */
/**
- * String with special formatting
- * @typedef {string} StackEntry
+ * Single-linked-list entry for the stack
+ * @typedef {Object} StackEntry
+ * @property {string | undefined} name
+ * @property {string | false} path
+ * @property {string} request
+ * @property {string} query
+ * @property {string} fragment
+ * @property {boolean} directory
+ * @property {boolean} module
+ * @property {StackEntry | undefined} parent
*/
/**
@@ -323,7 +331,7 @@ const {
* @property {WriteOnlySet<string>=} contextDependencies
* @property {WriteOnlySet<string>=} fileDependencies files that was found on file system
* @property {WriteOnlySet<string>=} missingDependencies dependencies that was not found on file system
- * @property {Set<StackEntry>=} stack set of hooks' calls. For instance, `resolve → parsedResolve → describedResolve`,
+ * @property {StackEntry=} stack set of hooks' calls. For instance, `resolve → parsedResolve → describedResolve`,
* @property {(function(string): void)=} log log function
* @property {ResolveContextYield=} yield yield result, if provided plugins can return several results
*/
@@ -350,24 +358,80 @@ function toCamelCase(str) {
return str.replace(/-([a-z])/g, str => str.slice(1).toUpperCase());
}
+/**
+ * @param {StackEntry | undefined} stack The tip of the existing stack
+ * @param {StackEntry} query The entry to look for
+ * @returns {boolean} If the stack contains the specified entry already
+ */
+function hasStackEntry(stack, query) {
+ while (stack) {
+ if (
+ stack.name === query.name &&
+ stack.path === query.path &&
+ stack.request === query.request &&
+ stack.query === query.query &&
+ stack.fragment === query.fragment &&
+ stack.directory === query.directory &&
+ stack.module === query.module
+ ) {
+ return true;
+ }
+ stack = stack.parent;
+ }
+ return false;
+}
+
+/**
+ * @param {StackEntry} entry The stack entry to format
+ * @returns {string} A formatted string representing the entry
+ */
+function formatStackEntry(entry) {
+ return (
+ entry.name +
+ ": (" +
+ entry.path +
+ ") " +
+ (entry.request || "") +
+ (entry.query || "") +
+ (entry.fragment || "") +
+ (entry.directory ? " directory" : "") +
+ (entry.module ? " module" : "")
+ );
+}
+
+/**
+ * @param {StackEntry} stack The tip of the stack to format
+ * @returns {string} The formatted stack
+ */
+function formatStack(stack) {
+ /** @type {StackEntry | undefined} */
+ let entry = stack;
+ let formatted = "";
+ while (entry) {
+ formatted = "\n " + formatStackEntry(entry) + formatted;
+ entry = stack.parent;
+ }
+ return formatted;
+}
+
class Resolver {
/**
* @param {ResolveStepHook} hook hook
* @param {ResolveRequest} request request
+ * @param {StackEntry} [parent] parent stack entry
* @returns {StackEntry} stack entry
*/
- static createStackEntry(hook, request) {
- return (
- hook.name +
- ": (" +
- request.path +
- ") " +
- (request.request || "") +
- (request.query || "") +
- (request.fragment || "") +
- (request.directory ? " directory" : "") +
- (request.module ? " module" : "")
- );
+ static createStackEntry(hook, request, parent) {
+ return {
+ name: hook.name,
+ path: request.path,
+ request: request.request || "",
+ query: request.query || "",
+ fragment: request.fragment || "",
+ directory: !!request.directory,
+ module: !!request.module,
+ parent
+ };
}
/**
@@ -670,33 +734,24 @@ class Resolver {
* @returns {void}
*/
doResolve(hook, request, message, resolveContext, callback) {
- const stackEntry = Resolver.createStackEntry(hook, request);
+ const parent = resolveContext.stack;
+ // Add a singly-linked list node to the stack
+ const stackEntry = Resolver.createStackEntry(hook, request, parent);
- /** @type {Set<string> | undefined} */
- let newStack;
- if (resolveContext.stack) {
- newStack = new Set(resolveContext.stack);
- if (resolveContext.stack.has(stackEntry)) {
+ if (parent) {
+ if (hasStackEntry(parent, stackEntry)) {
/**
* Prevent recursion
* @type {Error & {recursion?: boolean}}
*/
const recursionError = new Error(
- "Recursion in resolving\nStack:\n " +
- Array.from(newStack).join("\n ")
+ "Recursion in resolving\nStack:" + formatStack(stackEntry)
);
recursionError.recursion = true;
if (resolveContext.log)
resolveContext.log("abort resolving because of recursion");
return callback(recursionError);
}
- newStack.add(stackEntry);
- } else {
- // creating a set with new Set([item])
- // allocates a new array that has to be garbage collected
- // this is an EXTREMELY hot path, so let's avoid it
- newStack = new Set();
- newStack.add(stackEntry);
}
this.hooks.resolveStep.call(hook, request);
@@ -708,7 +763,7 @@ class Resolver {
fileDependencies: resolveContext.fileDependencies,
contextDependencies: resolveContext.contextDependencies,
missingDependencies: resolveContext.missingDependencies,
- stack: newStack
+ stack: stackEntry
},
message
);
diff --git a/types.d.ts b/types.d.ts
index fc09289..8b77196 100644
--- a/types.d.ts
+++ b/types.d.ts
@@ -685,7 +685,7 @@ declare interface ResolveContext {
/**
* set of hooks' calls. For instance, `resolve → parsedResolve → describedResolve`,
*/
- stack?: Set<string>;
+ stack?: StackEntry;
/**
* log function
@@ -982,6 +982,16 @@ declare abstract class Resolver {
join(path: string, request: string): string;
normalize(path: string): string;
}
+declare interface StackEntry {
+ name?: string;
+ path: string | false;
+ request: string;
+ query: string;
+ fragment: string;
+ directory: boolean;
+ module: boolean;
+ parent?: StackEntry;
+}
declare interface Stat {
(
path: PathLike,
From 8bd21dd7b0f961ede4c8972f15a26830621dfd00 Mon Sep 17 00:00:00 2001
From: David Michon <dmichon@microsoft.com>
Date: Mon, 13 Jan 2025 21:46:21 +0000
Subject: [PATCH 2/2] fix: infinite loop
---
lib/Resolver.js | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/Resolver.js b/lib/Resolver.js
index 6315663..b78cbd6 100644
--- a/lib/Resolver.js
+++ b/lib/Resolver.js
@@ -409,7 +409,7 @@ function formatStack(stack) {
let formatted = "";
while (entry) {
formatted = "\n " + formatStackEntry(entry) + formatted;
- entry = stack.parent;
+ entry = entry.parent;
}
return formatted;
}