Duration is a Zed extension that adds code actions for calculating time ranges in Markdown and Plain Text buffers.

• Markdown and Plain Text only
• Code actions for the current line or current selection
• Time-range syntax using -
• Pure Rust time parsing and duration math with no external conversion dependency

Place the cursor on a line such as 10:00 - 12:00, 14:00 - 17:00, or 23:00 - 2:00, then open code actions in Zed and choose one of these actions:

• Calculate duration
• Calculate duration on line

The extension rewrites the text to include the result, for example 10:00 - 12:30 = 2.5 hours.

This repository pins Rust 1.94.0 via rust-toolchain.toml for consistent local builds. The Zed extension itself is compiled for wasm32-wasip2, so make sure that target is installed too.

1. Install the language server binary on your PATH:

   cargo install --path language-server

2. Install the Rust target Zed needs for compiling the extension:

   rustup target add wasm32-wasip2 --toolchain 1.94.0

3. Install this repository as a dev extension in Zed with zed: install dev extension.

4. Test from a saved Markdown or Plain Text file.

Supported v1 input examples:

• 10:00 - 12:00 = 2 hours
• 14:00 - 17:00 = 3 hours
• 23:00 - 2:00 = 3 hours
• 9:00 - 11:15 = 2.25 hours

cargo check -p duration
cargo test -p duration-language-server

• The outer parser is intentionally small and only owns the time-range syntax on each line.
• Cross-midnight ranges are treated as next-day durations when the end time is earlier than the start time.
• v1 only supports 24-hour H:MM and HH:MM input.