Git Blame on Hover

A DeepSeek Harness plugin. When a text or source file is opened in the right sidebar's file preview, hovering a line shows a small card with that line's git blame information (author, short commit hash, date, and commit summary).

Install

Requires DeepSeek Harness; this plugin targets DSH ^0.2.1-rc.5.

• From npm: open the Plugins page → 添加插件 / Add plugin and enter the package name dsh-plugin-git-blame, or run dsh plugin add dsh-plugin-git-blame.
• From this repository (git): in the same dialog paste the repository URL, or run dsh plugin add github:badpx/dsh-plugin-git-blame.

Discoverability (plugin market)

DSH does not crawl GitHub or npm on its own. Third-party plugins are surfaced by the experimental plugin market: a Discover tab that reads plugin market index JSON documents whose URLs you add in Settings. The index follows format 1 of @deepseek-ai/dsh-plugin-market-index; its plugins[].versions[].source is either { "type": "npm" } or a git entry pinned to a full 40-hex commit:

{
  "format": 1,
  "title": { "en": "My DSH plugins" },
  "plugins": [
    {
      "name": "dsh-plugin-git-blame",
      "title": { "en": "Git Blame" },
      "description": { "en": "Inline git blame gutter and hover bubble in the file preview." },
      "repository": { "url": "https://github.com/badpx/dsh-plugin-git-blame" },
      "icon": "https://raw.githubusercontent.com/badpx/dsh-plugin-git-blame/main/icon.svg",
      "versions": [
        {
          "version": "0.1.0",
          "publishTimestamp": 1740000000,
          "source": {
            "type": "git",
            "url": "https://github.com/badpx/dsh-plugin-git-blame",
            "commit": "<40-hex-commit-sha>"
          }
        }
      ]
    }
  ]
}

Host the index over https and add that URL in the Discover/Settings UI. This repository ships a ready-made market-index.json; add its raw URL https://raw.githubusercontent.com/badpx/dsh-plugin-git-blame/main/market-index.json as an index source. After publishing to npm you can switch a version to "source": { "type": "npm" } (the installer builds the exact name@version). Git sources are commit-pinned, so refresh the commit on each release.

How it works

• Host (index.js): registers GET /plugin/git-blame?sessionId=&path=&line=. It resolves the file against the Session's working directory, runs git blame --line-porcelain -L <line>,<line> -- <file>, and returns JSON. Only files inside the Session working directory are eligible.
• Client (client.js): registers one occupant of shell.overlay. A pointer-move listener detects when the pointer is over a line in [data-code-preview] or [data-textpreview-plain] inside the right sidebar, maps the hovered tab to its dsh-resource://file/... address, and asks the Host route for the blame of that line.

A toggle button in the preview header turns the inline blame column on or off and remembers the choice. Both the toggle and the column only appear for files that are text and tracked by Git; untracked or binary files show neither.

Inline blame column

For the built-in highlighted code preview the plugin injects a fixed-width gutter column just left of the line numbers. Each row shows date + author (truncated with an ellipsis), and rows are tinted by commit SHA so the same commit shares one colour. Hovering that column shows the blame bubble; hovering the code lines themselves shows nothing.

A shortcut command "显示/关闭 Git Blame 气泡" is registered but left unbound; assign it a key in Settings → Shortcuts, and the current keycaps appear in the toggle's tooltip.

Notes

• The preview is read-only, so the interaction uses the mouse pointer rather than a text caret.
• Hovering the blame gutter column shows the bubble immediately; leaving the column hides it immediately.
• The bubble follows just below the cursor. When there is not enough room near the bottom edge it flips above the cursor while keeping the same gap.
• The card is slightly translucent (opacity 0.85). After ~9 s without pointer movement it fades over 1 s to opacity 0.15 so it stops hiding the code below; any pointer movement restores it.
• The commit message is shown as a bold first-line title plus a normal body; the body is capped at 5 lines and ends with an ellipsis when truncated. When a commit has only a single-line message, that line wraps and uses the full 5-line budget instead of being clamped to one line.
• Blame is shared per file+commit: consecutive rows belonging to the same commit reuse a single cache entry, so moving the pointer across them is instant and triggers no reload. Uncommitted rows keep per-line caching.

Caching

• Whole-file blame cache (gutterCache): an in-memory LRU keyed by file address + snapshot version, holding the parsed per-line array the gutter renders. Bounded by a 64 MB byte budget, at most 200 entries, and a single file whose line data exceeds 16 MB is not cached; least-recently-used entries are evicted (no clear-all cliff). Concurrent reads of the same file+version are coalesced into one request, and the bubble reuses the mapping the sidebar already holds — so even a too-large-to-cache file never refetches blame per hover.
• Client bubble cache: a bounded LRU (2000 entries, 600 s TTL). For committed rows the key is file address + commit SHA, so every row of one commit shares a single entry and moving the pointer across those rows is instant (no reload). Uncommitted rows are keyed by file address + content version + line. The snapshot version is HEAD + file size + mtime + ctime from one safe open (reused for ~1 s), and the host confirms HEAD is unchanged across the read and blame, so switching branches or editing shifts each line to the right commit and stale blame is never served — without hashing whole files on every probe.
• Host commit-message cache: keyed by full commit SHA with a 500-entry LRU. Failures are never cached, so a transient git show error is retried.
• Files outside a Git repository, or lines that are not tracked, show a short explanatory message instead of a commit.