feat(extraction): add Solidity language support

.claude/skills/agent-eval/corpus.json

@@ -94,5 +94,10 @@
     { "name": "react-native-segmented-control", "repo": "https://github.com/react-native-segmented-control/segmented-control", "size": "Small", "files": "~25", "question": "How does JSX `<SegmentedControl onChange={cb}/>` reach the native onChange handler on iOS/Android?" },
     { "name": "react-native-screens", "repo": "https://github.com/software-mansion/react-native-screens", "size": "Medium", "files": "~1200", "question": "How does JSX `<ScreenStack>` reach the native RNSScreenStackView component?" },
     { "name": "react-native-skia", "repo": "https://github.com/Shopify/react-native-skia", "size": "Large", "files": "~1000", "question": "How does a `<SkiaPictureView/>` JSX usage reach the iOS / Android native renderer?" }
+  ],
+  "Solidity": [
+    { "name": "solmate", "repo": "https://github.com/transmissions11/solmate", "size": "Small", "files": "~60", "question": "How does solmate's ERC20 transferFrom enforce allowance and update balances? Trace the flow including the permit() signature path." },
+    { "name": "solady", "repo": "https://github.com/Vectorized/solady", "size": "Medium", "files": "~270", "question": "How does solady's ERC20 implementation handle a permit() call — from signature recovery through nonce update to allowance write?" },
+    { "name": "openzeppelin-contracts", "repo": "https://github.com/OpenZeppelin/openzeppelin-contracts", "size": "Large", "files": "~400", "question": "How does an OpenZeppelin AccessControl-protected function check the caller's role? Trace from the onlyRole modifier through hasRole to the role storage." }
   ]
 }

CHANGELOG.md

@@ -11,6 +11,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### New Features
 
+- CodeGraph now indexes **Solidity** (`.sol`) — contracts, libraries, interfaces, structs, enums, modifiers, events, errors, and state variables become first-class symbols, with call edges that follow `emit`, `revert`, and library/method calls (including `using` directives). `import` directives resolve to the imported file, so cross-contract questions like "trace `transferFrom` through allowance and balance updates" or "how does `onlyRole` reach the role storage?" work out of the box on real Solidity codebases (validated on solmate, solady, and OpenZeppelin Contracts).
 - `codegraph status --json` now also reports the running CLI `version`, the index directory (`indexPath`), and a `lastIndexed` timestamp (ISO-8601, or null when nothing's indexed yet), so CI and scripts can pin the CLI version and check index freshness from a single command. A matching `CodeGraph.getLastIndexedAt()` library method exposes the same freshness check without shelling out. Thanks @12122J and @eddieran. (#329)
 
 ### Fixes

README.md

@@ -215,7 +215,7 @@ CodeGraph cuts **tokens, tool calls, and wall-clock time on every repo** — acr
 | **Full-Text Search** | Find code by name instantly across your entire codebase, powered by FTS5 |
 | **Impact Analysis** | Trace callers, callees, and the full impact radius of any symbol before making changes |
 | **Always Fresh** | File watcher uses native OS events (FSEvents/inotify/ReadDirectoryChangesW) with debounced auto-sync — the graph stays current as you code, zero config |
-| **20+ Languages** | TypeScript, JavaScript, Python, Go, Rust, Java, C#, PHP, Ruby, C, C++, Objective-C, Swift, Kotlin, Dart, Lua, Luau, Svelte, Liquid, Pascal/Delphi |
+| **20+ Languages** | TypeScript, JavaScript, Python, Go, Rust, Java, C#, PHP, Ruby, C, C++, Objective-C, Swift, Kotlin, Dart, Lua, Luau, Solidity, Svelte, Liquid, Pascal/Delphi |
 | **Framework-aware Routes** | Recognizes web-framework routing files and links URL patterns to their handlers across 14 frameworks |
 | **Mixed iOS / React Native / Expo** | Closes cross-language flows that static parsing misses: Swift ↔ ObjC bridging, React Native legacy bridge + TurboModules + Fabric view components, native → JS event emitters, Expo Modules |
 | **100% Local** | No data leaves your machine. No API keys. No external services. SQLite database only |
@@ -627,6 +627,7 @@ is written):
 | Pascal / Delphi | `.pas`, `.dpr`, `.dpk`, `.lpr` | Full support (classes, records, interfaces, enums, DFM/FMX form files) |
 | Lua | `.lua` | Full support (functions, methods with receivers, local variables, `require` imports, call edges) |
 | Luau | `.luau` | Full support (everything in Lua, plus `type`/`export type` aliases, typed signatures, and Roblox instance-path `require`) |
+| Solidity | `.sol` | Full support (contracts, libraries, interfaces, structs, enums, modifiers, events, errors, state variables, `import`/`using` directives, `emit`/`revert` calls) |
 
 ## Troubleshooting
 

__tests__/extraction.test.ts

@@ -101,6 +101,10 @@ describe('Language Detection', () => {
     expect(detectLanguage('stdio.h', '#ifndef STDIO_H\nvoid printf();\n#endif\n')).toBe('c');
   });
 
+  it('should detect Solidity files', () => {
+    expect(detectLanguage('contracts/Vault.sol')).toBe('solidity');
+  });
+
   it('should return unknown for unsupported extensions', () => {
     expect(detectLanguage('styles.css')).toBe('unknown');
     expect(detectLanguage('data.json')).toBe('unknown');
@@ -129,6 +133,7 @@ describe('Language Support', () => {
     expect(languages).toContain('swift');
     expect(languages).toContain('kotlin');
     expect(languages).toContain('dart');
+    expect(languages).toContain('solidity');
   });
 });
 
@@ -4414,6 +4419,179 @@ void helperFunction(int count) {
   });
 });
 
+describe('Solidity Extraction', () => {
+  const code = `// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+
+interface IVault {
+    function deposit(uint256 amount) external returns (bool);
+    event Deposited(address indexed user, uint256 amount);
+}
+
+library SafeMath {
+    function add(uint256 a, uint256 b) internal pure returns (uint256) {
+        return a + b;
+    }
+}
+
+contract Vault is IVault {
+    using SafeMath for uint256;
+
+    enum Status { Active, Frozen, Closed }
+
+    struct UserInfo {
+        uint256 balance;
+        uint256 lastDeposit;
+    }
+
+    IERC20 public immutable token;
+    mapping(address => UserInfo) public users;
+    address public owner;
+
+    event Withdrawn(address indexed user, uint256 amount);
+    error NotOwner();
+
+    modifier onlyOwner() {
+        if (msg.sender != owner) revert NotOwner();
+        _;
+    }
+
+    constructor(address _token) {
+        token = IERC20(_token);
+        owner = msg.sender;
+    }
+
+    function deposit(uint256 amount) external override returns (bool) {
+        users[msg.sender].balance = users[msg.sender].balance.add(amount);
+        emit Deposited(msg.sender, amount);
+        return true;
+    }
+
+    function withdraw(uint256 amount) external onlyOwner {
+        emit Withdrawn(msg.sender, amount);
+    }
+}
+`;
+
+  describe('Language detection', () => {
+    it('should detect Solidity files', () => {
+      expect(detectLanguage('contracts/Vault.sol')).toBe('solidity');
+    });
+
+    it('should report Solidity as supported', () => {
+      expect(isLanguageSupported('solidity')).toBe(true);
+      expect(getSupportedLanguages()).toContain('solidity');
+    });
+  });
+
+  describe('Container extraction', () => {
+    it('should extract contract / interface / library as class-likes', () => {
+      const result = extractFromSource('Vault.sol', code);
+      // interface_declaration → interface
+      const iface = result.nodes.find((n) => n.kind === 'interface' && n.name === 'IVault');
+      expect(iface).toBeDefined();
+      expect(iface?.language).toBe('solidity');
+      // contract and library both map to 'class' (library has no special semantics
+      // a class node doesn't already cover — they share methodTypes/inheritance).
+      expect(result.nodes.find((n) => n.kind === 'class' && n.name === 'Vault')).toBeDefined();
+      expect(result.nodes.find((n) => n.kind === 'class' && n.name === 'SafeMath')).toBeDefined();
+    });
+
+    it('should emit extends references for `is X, Y` inheritance', () => {
+      // `Vault is IVault` — Solidity uses one keyword (`is`) for both class
+      // extension and interface implementation, so the extractor emits `extends`
+      // and the resolver's interface-impl synthesizer reclassifies to
+      // `implements` based on the target node kind.
+      const result = extractFromSource('Vault.sol', code);
+      const extendsRefs = result.unresolvedReferences.filter(
+        (r) => r.referenceKind === 'extends' && r.referenceName === 'IVault'
+      );
+      expect(extendsRefs).toHaveLength(1);
+      const vaultNode = result.nodes.find((n) => n.kind === 'class' && n.name === 'Vault');
+      expect(extendsRefs[0]?.fromNodeId).toBe(vaultNode?.id);
+    });
+  });
+
+  describe('Method extraction', () => {
+    it('should extract methods, modifiers, and constructor with signatures', () => {
+      const result = extractFromSource('Vault.sol', code);
+      const methods = result.nodes.filter((n) => n.kind === 'method');
+      const names = methods.map((n) => n.name);
+      expect(names).toContain('deposit');
+      expect(names).toContain('withdraw');
+      expect(names).toContain('add');
+      expect(names).toContain('onlyOwner');     // modifier_definition
+      expect(names).toContain('constructor');   // constructor_definition (synthetic name)
+
+      // Signature should capture parameters + visibility + state mutability + return type.
+      const add = methods.find((m) => m.name === 'add');
+      expect(add?.signature).toContain('uint256 a');
+      expect(add?.signature).toContain('internal');
+      expect(add?.signature).toContain('pure');
+      expect(add?.signature).toContain('returns (uint256)');
+
+      // `external` visibility should map to 'public' (callable from outside the contract).
+      const deposit = methods.find((m) => m.name === 'deposit');
+      expect(deposit?.visibility).toBe('public');
+    });
+  });
+
+  describe('Struct, enum, and field extraction', () => {
+    it('should extract struct, enum, and enum members', () => {
+      const result = extractFromSource('Vault.sol', code);
+      expect(result.nodes.find((n) => n.kind === 'struct' && n.name === 'UserInfo')).toBeDefined();
+      expect(result.nodes.find((n) => n.kind === 'enum' && n.name === 'Status')).toBeDefined();
+      const enumMembers = result.nodes.filter((n) => n.kind === 'enum_member').map((n) => n.name);
+      expect(enumMembers).toEqual(expect.arrayContaining(['Active', 'Frozen', 'Closed']));
+    });
+
+    it('should extract state variables, struct members, events, errors as fields', () => {
+      const result = extractFromSource('Vault.sol', code);
+      const fieldNames = result.nodes.filter((n) => n.kind === 'field').map((n) => n.name);
+      // state variables
+      expect(fieldNames).toEqual(expect.arrayContaining(['token', 'users', 'owner']));
+      // struct members
+      expect(fieldNames).toEqual(expect.arrayContaining(['balance', 'lastDeposit']));
+      // event + error
+      expect(fieldNames).toEqual(expect.arrayContaining(['Deposited', 'Withdrawn', 'NotOwner']));
+    });
+
+    it('should treat `constant_variable_declaration` as a constant, not a variable', () => {
+      const constCode = `// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+uint256 constant FILE_CONST = 42;
+`;
+      const result = extractFromSource('consts.sol', constCode);
+      const node = result.nodes.find((n) => n.name === 'FILE_CONST');
+      expect(node?.kind).toBe('constant');
+    });
+  });
+
+  describe('Import and call extraction', () => {
+    it('should extract import directives with the source path as the module name', () => {
+      const result = extractFromSource('Vault.sol', code);
+      const imp = result.nodes.find((n) => n.kind === 'import');
+      expect(imp).toBeDefined();
+      expect(imp?.name).toBe('@openzeppelin/contracts/token/ERC20/IERC20.sol');
+    });
+
+    it('should produce calls refs for emit, revert, and library/method calls', () => {
+      const result = extractFromSource('Vault.sol', code);
+      const calls = result.unresolvedReferences
+        .filter((r) => r.referenceKind === 'calls')
+        .map((r) => r.referenceName);
+      // emit Deposited(...)
+      expect(calls).toContain('Deposited');
+      // revert NotOwner()
+      expect(calls).toContain('NotOwner');
+      // library call: balance.add(amount) — receiver-qualified
+      expect(calls.some((c) => c === 'add' || c === 'balance.add')).toBe(true);
+    });
+  });
+});
+
 describe('Regression: issue-specific extraction fixes', () => {
   it('indexes inner functions of an anonymous AMD/CommonJS module wrapper (#528)', () => {
     const code = `

src/extraction/grammars.ts

@@ -38,6 +38,7 @@ const WASM_GRAMMAR_FILES: Record<GrammarLanguage, string> = {
   lua: 'tree-sitter-lua.wasm',
   luau: 'tree-sitter-luau.wasm',
   objc: 'tree-sitter-objc.wasm',
+  solidity: 'tree-sitter-solidity.wasm',
 };
 
 /**
@@ -101,6 +102,7 @@ export const EXTENSION_MAP: Record<string, Language> = {
   '.luau': 'luau',
   '.m': 'objc',
   '.mm': 'objc',
+  '.sol': 'solidity',
   // XML: file-level tracking; the MyBatis extractor matches `<mapper namespace="...">`
   // shape and emits SQL-statement nodes (other XML returns empty).
   '.xml': 'xml',
@@ -384,6 +386,7 @@ export function getLanguageDisplayName(language: Language): string {
     lua: 'Lua',
     luau: 'Luau',
     objc: 'Objective-C',
+    solidity: 'Solidity',
     yaml: 'YAML',
     twig: 'Twig',
     xml: 'XML',

src/extraction/languages/index.ts

@@ -26,6 +26,7 @@ import { scalaExtractor } from './scala';
 import { luaExtractor } from './lua';
 import { luauExtractor } from './luau';
 import { objcExtractor } from './objc';
+import { solidityExtractor } from './solidity';
 
 export const EXTRACTORS: Partial<Record<Language, LanguageExtractor>> = {
   typescript: typescriptExtractor,
@@ -49,4 +50,5 @@ export const EXTRACTORS: Partial<Record<Language, LanguageExtractor>> = {
   lua: luaExtractor,
   luau: luauExtractor,
   objc: objcExtractor,
+  solidity: solidityExtractor,
 };