coc-diffview

Editable unified and side-by-side diff UI for coc.nvim.

coc-diffview deliberately has no knowledge of Git, repositories, revisions, or file history. Extensions such as coc-git resolve the two documents and pass them to this extension as an original and a modified source.

The modified source remains editable. When it is an existing buffer, edits are made directly in that buffer. Unified annotations are recomputed after every buffer change without moving the cursor. Split views use Neovim's diff mode and synchronize scrolling and cursor movement.

API

import type { CocDiffviewApi } from "@statiolake/coc-diffview";

await diffview.open({
  original: {
    kind: "text",
    text: contentsAtHead,
    label: "HEAD:src/index.ts",
    filetype: "typescript",
  },
  modified: {
    kind: "buffer",
    buffer: bufnr,
    label: "src/index.ts",
  },
  layout: "unified", // or "split"
});

Both sources accept { kind: "buffer", buffer } or { kind: "text", text, label, filetype? }. A text modified source is an editable scratch buffer; a buffer modified source edits the real document.

The diffview.open command accepts the same options object. Use diffview.close to remove the active diff session.

• diffview.toggleLayout switches the active diff between unified and side-by-side layouts.
• diffview.toggle switches between the diff and the normal modified buffer. It accepts optional diff options, allowing a provider to toggle the diff associated with the current buffer rather than only the latest input.

Unified added, removed, and changed lines use CocDiffviewAdded, CocDiffviewRemoved, and CocDiffviewChanged. They default to DiffAdd, DiffDelete, and DiffChange, matching Neovim's side-by-side diff colors.