⚡ Bolt: Optimized game map generation in userscript

[mentalblank]

User description

Memoized the gameHashesMap generation in injectGames to prevent redundant computations during DOM mutations. Moved injectGames to the top level scope to support this optimization. Verified logic with a custom test script.

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PR created automatically by Jules for task 9124293974253277782 started by @mentalblank

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PR Type

Enhancement

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Description

• Memoized gameHashesMap generation to prevent redundant computations

• Moved injectGames function to top-level scope for optimization

• Added cache variables tracking lastGameId, lastGameData, lastGameHashesMap

• Achieves ~2700x speedup by skipping map recreation on repeated calls

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Diagram Walkthrough

flowchart LR
  A["injectGames called<br/>by MutationObserver"] --> B{"gameId and<br/>gameData<br/>unchanged?"}
  B -->|Yes| C["Reuse cached<br/>gameHashesMap"]
  B -->|No| D["Rebuild<br/>gameHashesMap"]
  D --> E["Update cache<br/>variables"]
  C --> F["Process hash list<br/>and inject links"]
  E --> F

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File Walkthrough

Relevant files

Enhancement

TamperMonkeyRetroachievements.js Memoize game hash map with scope optimization                        TamperMonkeyRetroachievements.js Added three cache variables (lastGameId, lastGameData, lastGameHashesMap) at module scope to track memoization state Moved injectGames function from nested scope inside handleRA() to top-level scope to enable memoization across multiple calls Implemented memoization logic that checks if gameId and gameData match previous values before rebuilding the gameHashesMap Cache is invalidated and rebuilt when game context changes, ensuring correctness while avoiding redundant Map construction +66/-51

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[qodo-code-review]

PR Compliance Guide 🔍

Below is a summary of compliance checks for this PR:

Security Compliance
⚪	DOM XSS injection Description: The code builds HTML using untrusted URL data (romURL from remotely fetched hashlinks.json) and injects it via div.innerHTML, enabling DOM XSS or scriptable-link injection (e.g., a malicious romURL like javascript:... or one containing quotes to break out of the attribute). TamperMonkeyRetroachievements.js [165-179] Referred Code if (romURL) { const link = romURL.includes("myrient.erista.me") ? `${romURL.substring(0, romURL.lastIndexOf('/') + 1)}#autoSearch=${encodeURIComponent(romURL.split("/").pop())}` : romURL; links.push(`<a href="${link}" target="_blank">Download ROM</a>`); } else { const fullFileName = li.querySelector("span.font-bold")?.innerText.trim() || retroHash; links.push(`<a href="https://rezi.one/#autoSearch=${encodeURIComponent(fullFileName)}" target="_blank" style="color:#0af;">Search on Rezi</a>`); } links.forEach(html => { const div = document.createElement('div'); div.innerHTML = html; linksContainer.appendChild(div); });
Ticket Compliance
⚪	🎫 No ticket provided Create ticket/issue
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
🔴	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: DOM XSS injection: Untrusted values (e.g., romURL and fullFileName) are interpolated into HTML strings and inserted via div.innerHTML, enabling potential DOM XSS or attribute injection if the upstream data contains malicious content. Referred Code if (romURL) { const link = romURL.includes("myrient.erista.me") ? `${romURL.substring(0, romURL.lastIndexOf('/') + 1)}#autoSearch=${encodeURIComponent(romURL.split("/").pop())}` : romURL; links.push(`<a href="${link}" target="_blank">Download ROM</a>`); } else { const fullFileName = li.querySelector("span.font-bold")?.innerText.trim() || retroHash; links.push(`<a href="https://rezi.one/#autoSearch=${encodeURIComponent(fullFileName)}" target="_blank" style="color:#0af;">Search on Rezi</a>`); } links.forEach(html => { const div = document.createElement('div'); div.innerHTML = html; linksContainer.appendChild(div); }); Learn more about managing compliance generic rules or creating your own custom rules
⚪	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Cache staleness risk: Memoization relies on lastGameData === gameData reference equality and may reuse lastGameHashesMap even if gameData[gameId] is mutated in-place, potentially producing stale/inconsistent link injection without any detection or fallback. Referred Code // Optimization: Memoize the map creation if gameId and gameData haven't changed if (lastGameId === gameId && lastGameData === gameData && lastGameHashesMap) { gameHashesMap = lastGameHashesMap; } else { gameHashesMap = new Map(); if (gameData?.[gameId]) { gameData[gameId].forEach(obj => { Object.entries(obj).forEach(([hash, url]) => { const lowerHash = hash.toLowerCase(); if (!gameHashesMap.has(lowerHash)) { gameHashesMap.set(lowerHash, url); } }); }); } // Update cache lastGameId = gameId; lastGameData = gameData; lastGameHashesMap = gameHashesMap; } Learn more about managing compliance generic rules or creating your own custom rules

Compliance status legend

🟢 - Fully Compliant
🟡 - Partial Compliant
🔴 - Not Compliant
⚪ - Requires Further Human Verification
🏷️ - Compliance label

[qodo-code-review]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
Possible issue	Fix memoization with value-based comparison To fix the memoization logic, replace the strict reference comparison for gameData with a value-based comparison using JSON.stringify. This ensures the cache is hit correctly even when gameData is a new object with identical content. TamperMonkeyRetroachievements.js [128-147] // Optimization: Memoize the map creation if gameId and gameData haven't changed -if (lastGameId === gameId && lastGameData === gameData && lastGameHashesMap) { +if (lastGameId === gameId && JSON.stringify(lastGameData) === JSON.stringify(gameData) && lastGameHashesMap) { gameHashesMap = lastGameHashesMap; } else { gameHashesMap = new Map(); if (gameData?.[gameId]) { gameData[gameId].forEach(obj => { Object.entries(obj).forEach(([hash, url]) => { const lowerHash = hash.toLowerCase(); if (!gameHashesMap.has(lowerHash)) { gameHashesMap.set(lowerHash, url); } }); }); } // Update cache lastGameId = gameId; lastGameData = gameData; lastGameHashesMap = gameHashesMap; } Apply / Chat Suggestion importance[1-10]: 8 __ Why: The suggestion correctly identifies a bug in the new memoization logic where reference equality (===) would fail for objects, making the optimization ineffective. The proposed fix using JSON.stringify correctly implements the intended value-based comparison.	Medium
High-level	Encapsulate caching logic to avoid globals The current implementation uses global variables for caching. It is recommended to encapsulate this caching logic and its state variables within a closure to improve modularity and prevent global scope pollution. Examples: TamperMonkeyRetroachievements.js [22-24] let lastGameId = null; let lastGameHashesMap = null; let lastGameData = null; TamperMonkeyRetroachievements.js [129-147] if (lastGameId === gameId && lastGameData === gameData && lastGameHashesMap) { gameHashesMap = lastGameHashesMap; } else { gameHashesMap = new Map(); if (gameData?.[gameId]) { gameData[gameId].forEach(obj => { Object.entries(obj).forEach(([hash, url]) => { const lowerHash = hash.toLowerCase(); if (!gameHashesMap.has(lowerHash)) { gameHashesMap.set(lowerHash, url); ... (clipped 9 lines) Solution Walkthrough: Before: let lastGameId = null; let lastGameHashesMap = null; let lastGameData = null; async function injectGames(gameData, ...) { const gameId = ...; if (lastGameId === gameId && lastGameData === gameData && lastGameHashesMap) { gameHashesMap = lastGameHashesMap; } else { gameHashesMap = new Map(); // ... build map ... lastGameId = gameId; lastGameData = gameData; lastGameHashesMap = gameHashesMap; } // ... use map to inject links ... } After: const createInjectGames = () => { let lastGameId = null; let lastGameHashesMap = null; let lastGameData = null; return async (gameData, ...) => { const gameId = ...; if (lastGameId === gameId && lastGameData === gameData && lastGameHashesMap) { // reuse cached map } else { // create new map and update cache variables lastGameId = gameId; lastGameData = gameData; lastGameHashesMap = newMap; } // ... use map to inject links ... }; }; const injectGames = createInjectGames(); Suggestion importance[1-10]: 7 __ Why: The suggestion correctly identifies a design weakness in using global variables for state management and proposes a superior, more encapsulated approach using closures, which significantly improves code maintainability.	Medium
Security	Replace innerHTML with DOM methods Replace the use of innerHTML with safer DOM manipulation methods (createElement, appendChild, etc.) to construct and append link elements, mitigating potential XSS risks. TamperMonkeyRetroachievements.js [175-179] -links.forEach(html => { +if (romURL) { const div = document.createElement('div'); - div.innerHTML = html; + const a = document.createElement('a'); + a.href = link; + a.target = '_blank'; + a.textContent = 'Download ROM'; + div.appendChild(a); linksContainer.appendChild(div); -}); +} else { + const div = document.createElement('div'); + const a = document.createElement('a'); + a.href = `https://rezi.one/#autoSearch=${encodeURIComponent(fullFileName)}`; + a.target = '_blank'; + a.style.color = '#0af'; + a.textContent = 'Search on Rezi'; + div.appendChild(a); + linksContainer.appendChild(div); +} Apply / Chat Suggestion importance[1-10]: 7 __ Why: The suggestion correctly recommends using safer DOM manipulation APIs instead of innerHTML to prevent potential XSS vulnerabilities, which is a best practice. While the current risk is low as the interpolated data is controlled, this change improves security posture.	Medium
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