Optimize/refactor

[Mx-Iris]

No description provided.

[Copilot]

Pull Request Overview

This PR refactors and optimizes various modules across the project with a focus on updating test case definitions, streamlining symbol handling by replacing outdated MachOSymbol types with Symbol, and standardizing internal access modifiers (using the new “package” keyword). Additionally, several improvements have been made to metadata processing, demangling, and utility functions to enhance maintainability and consistency.

Reviewed Changes

Copilot reviewed 82 out of 88 changed files in this pull request and generated no comments.

File	Description
Tests/SwiftDumpTests/*	Updated test classes from structs to final classes and streamlined protocol names for dumpable tests
Sources/Utilities/MemoryPressureMonitor.swift	Changed class declaration and variable access to use “package” for improved internal encapsulation
Various Sources/MachOSwiftSection/* and Sources/MachOSymbols/*	Refactored symbol-related types by replacing MachOSymbol with Symbol and updated associated APIs accordingly
Package.swift	Added and rearranged dependency declarations (including swift-collections) to support new refactorings

Comments suppressed due to low confidence (3)

Tests/MachOSwiftSectionTests/SymbolDemangleTests.swift:21

• [nitpick] Clarify in a comment the rationale for replacing standard print statements with the new .print() method to ensure that team members understand the updated logging approach in symbol demangling tests.

        "Total Swift Symbols: \(allSwiftSymbols.count)".print()

Sources/MachOSwiftSection/Models/Type/Class/Class.swift:30

• Ensure that changing from a dynamicMemberLookup struct to a plain struct does not affect existing member access patterns, and update documentation or comments if special handling was previously expected.

public struct Class: TopLevelType {

Sources/Utilities/MemoryPressureMonitor.swift:3

• [nitpick] Verify that using the 'package' access modifier here is consistent with project practices and document its intended scope to help new contributors understand its role.

package class MemoryPressureMonitor {

[gemini-code-assist]

Summary of Changes

Hello @Mx-Iris, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces significant architectural improvements and optimizations across several core modules, primarily focusing on Swift symbol demangling, Mach-O file analysis, and efficient symbol management. The changes aim to enhance the performance, extensibility, and maintainability of the codebase by introducing new data structures, protocols, and caching mechanisms, alongside a comprehensive refactor of existing components.

Highlights

• Core Demangling Refactor: The Demangle module has undergone a significant architectural overhaul. The core Node structure is now a final class with an improved Contents enum and a comprehensive set of mutation methods. New protocols (NodePrinterTarget) and structs (NodePrintContext, NodePrintState) have been introduced to provide a more flexible and extensible printing mechanism for demangled nodes. Utility extensions for Node (e.g., isSimpleType, isProtocol) and Node.Kind (now String raw-representable) enhance usability and clarity.
• Enhanced Mach-O Swift Section Analysis: The MachOSwiftSection module has been heavily refactored to improve how Swift metadata is read and represented. New protocols like SwiftSectionRepresentable, TopLevelDescriptor, TopLevelType, and MachOSwiftSectionRepresentableWithCache standardize access patterns. The descriptor reading logic now differentiates between direct and relative pointer-based descriptors, and support for BuiltinType descriptors has been added. Existing Swift metadata models (e.g., Class, Enum, Protocol) now conform to TopLevelType, centralizing common properties and dynamic member lookups.
• Robust Symbol Management and Caching: A new MachOSymbols module has been introduced to provide efficient symbol handling. The MachOSymbol struct has been renamed to Symbol and made a value type. Central to this module are SymbolCache and SymbolIndexStore, which offer caching and intelligent indexing of Swift symbols (categorized by kind like functions, variables, allocators, and their static/extension contexts) within Mach-O files. This significantly improves lookup performance and enables more granular symbol analysis.
• Improved Testing Infrastructure: The testing framework in MachOTestingSupport has been revamped with new base classes (DyldCacheTests, MachOFileTests, MachOImageTests, XcodeMachOFileTests) to reduce boilerplate and standardize test setups across different Mach-O contexts. The DumpableTests protocol has been extended to include new dumping capabilities, and the SwiftStdlibDemangle utility has been relocated for better organization.
• Semantic Output for SwiftDump: The SwiftDump module now leverages the refactored Demangle and MachOSymbols capabilities to produce more semantically rich output. It integrates with the new SymbolIndexStore to display associated functions and variables for dumped enums and structs, and utilizes the new Node+SemanticString extension for styled, semantically meaningful demangled output.

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[gemini-code-assist]

Code Review

This is a massive and impressive pull request that goes far beyond simple optimization and refactoring. It fundamentally re-architects the demangling and printing pipeline, introduces sophisticated caching and indexing for symbols, and adds significant new features for dumping Swift metadata. The new abstractions like Node, NodePrinter, TopLevelType, and the various caching mechanisms are very well-designed.

I have one critical concern regarding the use of @unchecked Sendable on the mutable Node class, which could lead to data races. Please see the detailed comment.

Overall, this is an excellent set of changes that significantly improves the capabilities and robustness of the project.

[gemini-code-assist]

The Node class is marked as @unchecked Sendable, but it is a mutable class with methods that mutate its children array (e.g., addChild, removeChild). There is no internal synchronization (like a lock) to protect access to the children array.

If a Node instance is ever shared and mutated across concurrent contexts (e.g., different threads or tasks), this will lead to data races, which are undefined behavior. Using @unchecked Sendable silences compiler warnings but shifts the full responsibility of ensuring thread safety to the developer, which is risky in a library context.

To ensure thread safety, please consider one of the following approaches:

• Add internal synchronization: Use a lock (like NSLock or a serial DispatchQueue) to protect all access and mutation of the children array.
• Re-evaluate Sendability: If Node instances are not intended to be shared across threads, remove the @unchecked Sendable conformance. The call sites can then be updated to manage Node instances in a way that doesn't require Sendable.
• Document the concurrency contract: If you intend for the caller to be responsible for synchronization, this must be clearly and explicitly documented on the Node class, explaining the concurrency model and the caller's responsibilities.