Copilot Completion

Code completion VS Code extension powered by LLMs — supporting both GHOST FIM inline completions and NES (Next Edit Suggestion) predictive edits.

中文文档

Enable NES

[!note] Because latest VS Code has tightened its permission controls, the NES feature APIs are restricted to internal extensions only; hence, you must manually enable the Proposals API.

1. ctrl + shift + p and type Preferences: Configure Runtime Arguments
2. Add the following line to the argv.json file:

   {
       "enable-proposed-api": ["young-triangle.copilot-completions"]
   }
   

3. Restart VS Code to apply the changes.

Features

GHOST — FIM (Fill in the Middle) Inline Completion

• Ghost-text inline suggestions displayed directly in the editor as you type
• Prefix/suffix context sent to the model via configurable FIM prompt template
• Multi-line detection chain: ML model scoring, empty block detection, suffix presence, file size guard, and newline detection
• Tree-sitter powered block parsing for intelligent completion boundaries
• Suffix overlap trimming with configurable similarity thresholds
• Caching and debouncing for responsive UX

NES — Next Edit Suggestion

• Predicts the developer's next edit anywhere in the current file (not just at the cursor)
• Edit window resolution around the cursor with merge conflict marker awareness
• Cursor jump prediction: anticipates where the developer will navigate next. This feature is available, but predication will lead to extra twice request.
• Edit intent classification: high / medium / low aggressiveness filtering
• Response post-processing pipeline: boundary marker parsing → cursor tag stripping → line-level diff → suffix overlap trimming
• Multiple response format handlers: edit-window, code-block, edit-intent, unified XML, custom diff-patch

Supported LLM Backends

[!tip]

• Qwen2.5 coder is good performance for GHOST, which can run in local and provide better suggestion.
• Qwen3.5 9B MIT performs well for GHOST and NES individually.
• Qwen3.6 35B A3B and Qwen3.6 27B are good for NES.

Configuration

All settings are under the cc-completion prefix.

wordPattern

Through cc-completion.wordPatterns, you can configure the wordPatterns for a language, which affects the word recognition behavior of ctrl + rightarrow in GHOST.

• wordPattern is a regular expression used to match word boundaries — that is, it controls the boundaries for the ctrl + rightarrow word recognition feature.
• To add flags to wordPattern, use the /.../ug format. Usually, do not add flags unless the language requires global matching.
• Press ctrl + shift + p, type change language mode to check the current language id, and use * to represent replacing all languages.
• Configuring cc-completion.wordPatterns will override the language's default wordPattern, affecting advanced features such as code completion and suggestions. Please modify the default configuration with caution.

The official built-in default configuration is as follows:

{
    "cc-completion.wordPatterns":{
        "c": "(-?\\d*\\.\\d\\w*)|([^\\`\\~\\!\\@\\#\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "cpp": "(-?\\d*\\.\\d\\w*)|([^\\`\\~\\!\\@\\#\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "cuda-cpp": "(-?\\d*\\.\\d\\w*)|([^\\`\\~\\!\\@\\#\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "css": "(#?-?\\d*\\.\\d\\w*%?)|(::?[\\w-]*(?=[^,{;]*[,{]))|(([@#!])? [\\w-?]+%?|[@#!.])",
        "handlebars": "(-?\\d*\\.\\d\\w*)|([^\\`\\~\\!\\@\\$\\^\\&\\*\\(\\)\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\s]+)",
        "html": "(-?\\d*\\.\\d\\w*)|([^\\`\\~\\!\\@\\$\\^\\&\\*\\(\\)\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\s]+)",
        "less": "(#?-?\\d*\\.\\d\\w*%?)|(::?[\\w-]*(?=[^,{;]*[,{]))|(([@#!])? [\\w-?]+%?|[@#!.])",
        "markdown": "/(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})(((\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})|[_])?(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark}))*/ug",
        "php": "(-?\\d*\\.\\d\\w*)|([^\\-\\`\\~\\!\\@\\#\\%\\^\\&\\*\\(\\)\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "prompt": "/(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})(((\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})|[_])?(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark}))*/ug",
        "instructions": "/(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})(((\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})|[_])?(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark}))*/ug",
        "chatagent": "/(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})(((\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})|[_])?(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark}))*/ug",
        "skill": "/(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})(((\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark})|[_])?(\\p{Alphabetic}|\\p{Number}|\\p{Nonspacing_Mark}))*/ug",
        "restructuredtext": "[\\w-]*\\w[\\w-]*",
        "scss": "(#?-?\\d*\\.\\d\\w*%?)|(::?[\\w-]*(?=[^,{;]*[,{]))|(([@$#!.])? [\\w-?]+%?|[@#!$.])",
        "typescript": "(-?\\d*\\.\\d\\w*)|([^\\`\\@\\~\\!\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "typescriptreact": "(-?\\d*\\.\\d\\w*)|([^\\`\\@\\~\\!\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "jsonc": "(-?\\d*\\.\\d\\w*)|([^\\`\\@\\~\\!\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)",
        "json": "(-?\\d*\\.\\d\\w*)|([^\\`\\@\\~\\!\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)"
    }
}

example: Implement character-by-character confirmation for Chinese

{
    "cc-completion.wordPatterns": {
        "*": "(-?\\d*\\.\\d\\w*)|(-?[\u4e00-\u9fa5])|([^\\；\\，\\、\\’\\‘\\：\u4e00-\u9fa5\\“\\”\\【\\】\\？\\`\\~\\!\\@\\#\\%\\^\\&\\*\\(\\)\\-\\=\\+\\[\\{\\]\\}\\\\\\|\\;\\:\\'\\\"\\,\\.\\<\\>\\/\\?\\s]+)"
    },
}

GHOST Settings

NES Settings

Commands

Requirements

• VS Code ^1.110.0

Development

# Install dependencies
npm install

# Compile
npm run compile

# Watch mode
npm run watch

# Production build
npm run package

# Lint
npm run lint

Architecture

src/
├── completions/
│   ├── ghost/          # GHOST: FIM inline completion
│   │   └── multiline/  # Multi-line detection chain + tree-sitter
│   ├── nes/            # NES: Next Edit Suggestion
│   │   ├── core/       # Workflow, history, edit-window, result assembly
│   │   ├── response/   # Response pipeline, differ, filter chain
│   │   └── stubs/      # Data type stubs
│   └── shared/         # Shared LLM adapters and log service
├── common/             # Shared utilities (arrays, result type, suffix trim)
├── config/             # Configuration providers (GHOST + NES)
├── di/                 # Dependency injection container
├── test/               # Test suites
└── ui/                 # Status bar panel

References

• github copilot chat

License

MIT