Fix: Auto-resolve binary paths in prettier.prettierPath setting

[Copilot]

Description

When users configure prettier.prettierPath to a binary executable (e.g., /Users/user/.nvm/versions/node/v18.19.0/bin/prettier or node_modules/.bin/prettier), the extension fails with this.prettierModule.resolveConfigFile is not a function because it attempts to load the binary as a module directory.

Solution

Auto-detect and resolve binary paths to their containing module directories:

Path Resolution Logic:

• Detect file vs directory paths in getModuleFromPrettierPath
• Resolve symlinks to real paths (handles node_modules/.bin/prettier → node_modules/prettier/bin/prettier.cjs)
• Traverse up to find module directory based on bin or .bin parent directories
• Verify module identity via package.json name check

Security:

• Validate resolved paths contain node_modules or prettier to prevent symlink attacks
• Use hasOwnProperty checks when parsing JSON to prevent prototype pollution

Error Handling:

• Clear error messages when binary paths cannot be resolved
• Graceful fallback to bundled prettier on resolution failure
• Debug logging for troubleshooting path resolution issues

Backward Compatibility

Module directory paths continue to work unchanged. Binary path resolution is additive.

Related Issue

Fixes #3482

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Refactoring (no functional changes)
• CI/Build changes

Checklist

• I have read the CONTRIBUTING guidelines
• My code follows the code style of this project (npm run lint passes)
• I have run npm run prettier to format my code
• I have added/updated tests that prove my fix or feature works
• All new and existing tests pass (npm test)
• I have updated the CHANGELOG.md with a summary of my changes

Original prompt

---

This section details on the original issue you should resolve

<issue_title>this.prettierModule.resolveConfigFile is not a function error when formatting</issue_title>
<issue_description>### Summary

Prettier files a error message when using 'format document with -> prettier'

Github Repository to Reproduce Issue

Steps To Reproduce:

Prettier files a error message when using 'format document with -> prettier'

Expected result

Describe what should have happened.

Actual result

Here's the log:

👇 when I restarted the editor

["INFO" - 11:47:03 AM] Extension Name: esbenp.prettier-vscode.
["INFO" - 11:47:03 AM] Extension Version: 10.4.0.
["ERROR" - 11:47:03 AM] Error handling text editor change
["ERROR" - 11:47:03 AM] Failed to load Prettier instance: /Users/user/.nvm/versions/node/v18.19.0/bin/prettier
Error: Failed to load Prettier instance: /Users/user/.nvm/versions/node/v18.19.0/bin/prettier
    at t.PrettierMainThreadInstance.import (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:18055)
    at t.ModuleResolver.getPrettierInstance (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:5771)
    at t.default.handleActiveTextEditorChanged (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:10967)
    at t.default.handleActiveTextEditorChangedSync (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:10569)
    at t.default.registerDisposables (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:13735)
    at /Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:83500

👇when focusing any editor window

["ERROR" - 11:47:17 AM] Error handling text editor change
["ERROR" - 11:47:17 AM] Invalid version
Error: Invalid version
    at t.isAboveV3 (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:24917)
    at t.default.getSelectors (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:11745)
    at t.default.handleActiveTextEditorChanged (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:11131)

👇when trying 'format document with prettier'

["INFO" - 11:48:20 AM] Formatting file:///Users/user/Projects/xxx.tsx
["ERROR" - 11:48:20 AM] Error resolving prettier configuration for /Users/user/Projects/xxx.tsx
["ERROR" - 11:48:20 AM] this.prettierModule.resolveConfigFile is not a function
TypeError: this.prettierModule.resolveConfigFile is not a function
    at t.PrettierMainThreadInstance.resolveConfigFile (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:18684)
    at t.ModuleResolver.resolveConfig (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:6856)
    at t.ModuleResolver.getResolvedConfig (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:7735)
    at t.default.format (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:14767)
    at t.PrettierEditProvider.provideEdits (/Users/user/.vscode/extensions/esbenp.prettier-vscode-10.4.0/dist/extension.js:1:12876)

Additional information

VS Code Version: Version: 1.85.2 (Universal)

Prettier Extension Version: 10.4.0

Prettier package version: 3.2.2

Other Libs:
"@trivago/prettier-plugin-sort-imports": "^4.1.1",
"eslint-config-prettier": "8.5.0",
"eslint-plugin-prettier": "5.1.3",

OS and version: Mac OS 13.6.3 (22G436)

Prettier Log Output

LOG GOES HERE. DO NOT USE A SCREENSHOT, COPY AND PASTE THE TEXT

</issue_description>

Comments on the Issue (you are @copilot in this section)

@ntotten We need to have better error handling for this. Ideally we'd detect if the path is valid and show a useful error.

• Fixes this.prettierModule.resolveConfigFile is not a function error when formatting #3445

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.