High-performance, GPU-accelerated desktop viewer and editor for structured data.
Built with Rust and GPUI. Handcrafted zero-dependency parsers with exact source spans, bidirectional AST tree navigation, diagnostics, and instant formatting.

Supported Formats • Key Features • Shortcuts • Installation • Getting Started • Architecture

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Supported Formats

FileViewer automatically identifies the document format from the file extension (with seamless fallback to JSON for unrecognized extensions).

Format	Extensions	AST & Tree View	Format / Minify	Syntax Highlighting	Comments & Roundtrip
JSON	.json	Yes	Yes	Yes	Strict RFC 8259 parser with exact source byte spans
JSONC	.jsonc	Yes	Yes	Yes	Accepts // and /* */ comments, trailing commas preserved
JSONL	.jsonl, .ndjson	Yes	Yes	Yes	Line-oriented stream parsed into synthetic root array
TOML	.toml	Yes	Yes	Yes	Tables, inline tables, dotted keys, multiline CRLF & LF
YAML	.yaml, .yml	Yes	Yes	Yes	Block/flow collections, multiline folded/literal scalars, anchors & aliases

Format Highlights

• JSON & JSONC: Accepts // and /* */ comments and allows trailing commas in JSONC mode. Formatting and minification are line-oriented and never reserialize the AST, guaranteeing comments and blank lines survive intact.
• JSONL / NDJSON: Parsed as an ordered sequence of records, rendered in the tree view as a synthetic root array. UTF-8 BOMs are automatically stripped, and source spans are offset by the BOM length so cursor sync lands exactly on target.
• TOML: Robust support for standard key-value pairs, dotted keys, inline tables, table arrays ([[table]]), and multiline strings across both LF and Windows CRLF line endings.
• YAML: Covers block mappings, block sequences, flow collections, plain and quoted scalars (single and double-quoted with escape folding), block scalars with chomping and explicit indent indicators, anchors, aliases, and merge keys. Alias expansion is protected by a strict node budget to prevent expansion bombs without exhausting memory.

Tip

Check samples/feature-tour.yml for a comprehensive demonstration of YAML constructs, anchors, folded scalars, and tree synchronization.

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Key Features

• GPU-Accelerated Rendering: Built on GPUI (the UI framework developed for the Zed editor), providing hardware-accelerated 120 FPS rendering and smooth scrolling.
• Bidirectional Tree Navigation: Two-way synchronization between the code editor and the structural AST tree view. Clicking any node in the tree highlights its precise span in the document; moving the cursor in the editor automatically tracks and focuses the corresponding tree node.
• Handcrafted Parsers: Zero external parsing crates for JSON, JSONC, JSONL, TOML, and YAML. Every token, bracket, and node records precise byte offsets and line/column positions.
• Non-Destructive Formatting: Pretty-printing and minification normalize indentation without losing comments or whitespace context.
• Real-Time Validation Diagnostics: Instant feedback on syntax errors with exact line and column locations, visual markers, and a jump-to-error shortcut.
• Find, Replace & Symbol Search: Full in-document search, symbol jumping (Alt+Down / Alt+Up), soft word wrap (Alt+Z), and unlimited undo/redo.
• Native OS Integration: Professional Windows installer with Explorer context menu ("Open with FileViewer"), default file associations, and portable releases for both Windows and Linux.

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Keyboard Shortcuts

Shortcut	Action
Ctrl + O	Open file
Ctrl + S	Save document
Ctrl + Shift + F	Format document
Ctrl + F	Find in document
Ctrl + Z / Ctrl + Y	Undo / Redo
Ctrl + T	Toggle tree panel
Ctrl + Shift + E	Expand all tree nodes
Ctrl + Shift + C	Collapse all tree nodes
Alt + Z	Toggle word wrap
Alt + Down / Alt + Up	Jump to next / previous symbol

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Installation

Download prebuilt binaries directly from the Releases page.

Windows

• Installer (FileViewer-Setup-0.1.0.exe):
  • Automatically installs FileViewer to AppData\Local\Programs\FileViewer.
  • Configures optional Desktop and Start Menu shortcuts.
  • Registers the Windows Explorer right-click context menu: "Open with FileViewer" for all supported formats and generic files.
  • Optionally associates .json, .jsonc, .jsonl, .ndjson, .toml, .yaml, and .yml files to open with FileViewer by default.
  • Clean uninstaller via Windows Add or remove programs.
• Portable (FileViewer-0.1.0-windows-x86_64.zip):
  • Standalone executable requiring no installation or admin rights.
  • Embedded high-resolution multi-size Windows PE icon resources.

Linux

• Debian Package (.deb):

  sudo apt install ./file-viewer_0.1.0_amd64.deb

• Portable Bundle (.tar.xz):

  tar -xf file-viewer_0.1.0_linux-x86_64.tar.xz
  cd bundle
  ./install.sh                 # use --prefix DIR to choose custom directory
  file-viewer config.toml

  Run ./uninstall.sh to remove cleanly.

• Integrity Verification:

  sha256sum -c SHA256SUMS

macOS

Prebuilt macOS binaries will be available in future releases. To build from source on macOS:

cargo build --release

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Getting Started

Opening a File

Launch FileViewer directly with a path argument or press Ctrl+O from inside the application:

file-viewer path/to/document.yaml

Building from Source

Prerequisites

• Rust 1.76+ (rustup update)
• On Linux, GPUI link-time libraries:

  sudo apt install libxcb1-dev libxkbcommon-dev libxkbcommon-x11-dev

Build & Run

# Debug build & run
cargo run -- config.jsonc

# Release build
cargo build --release

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Building Release Artifacts

Windows Installer & Portable ZIP

powershell -ExecutionPolicy Bypass -File scripts\build-installer.ps1

Generates:

• dist/FileViewer-Setup-0.1.0.exe (Inno Setup installer)
• dist/FileViewer-0.1.0-windows-x86_64.zip (Portable ZIP)
• dist/SHA256SUMS

Linux Packages

packaging/linux/build_release.sh

Generates:

• dist/file-viewer_0.1.0_amd64.deb
• dist/file-viewer_0.1.0_linux-x86_64.tar.xz
• dist/SHA256SUMS

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Architecture & Technical Design

• Zero-Bloat Custom Parsers: Hand-written lexers and parsers designed specifically for precise byte-span tracking ($O(n)$ single-pass scanning). Unlike standard deserializers, FileViewer retains document structure, trivia, and exact coordinates.
• Line & Byte Span Synchronization: The editor maps visual screen lines and cursor offsets to AST node paths in $O(\log n)$ to $O(n)$ time, ensuring instant selection feedback without frame drops.
• Memory Safety & Expansion Budgets: Parsers enforce recursion depth bounds (default 128) and node expansion limits to prevent billion-laughs or deeply nested stack overflows.

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Testing

The project maintains a comprehensive test suite covering all parser dialects, round-tripping, syntax folding, BOM handling, and bidirectional synchronization:

cargo test

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License

This project is licensed under the MIT License.