dsh-diff-view
A DeepSeek Harness (DSH)
plugin: a reusable two-text diff viewer for client plugins, styled after the
harness's native changed-files review. Hunk headers, true line numbers on
both sides, split or unified, word-level highlights, and optional syntax
highlighting through the same engine the native review uses.
There is no UI of its own to visit. Plugins inject the client service
diffView:
// consumer client half, inject: ['diffView', …]
// 1. A FileDiff-styled component from two whole texts:
const Diff = ctx.diffView.diffFileComponent({
path: 'src/a.ts', // optional; selects the syntax grammar
before: oldText, // either before/after strings…
after: newText,
// …or pass precomputed hunks at render time instead:
// hunks: ctx.diffView.hunksOf(oldText, newText)
initialMode: 'split', // 'split' (default) | 'unified'
showToggle: true, // false hides the Split/Unified pill
wrap: false, // true wraps long lines instead of scrolling
wordHighlights: true, // false disables per-word marks
})
return React.createElement(Diff, {})
// Controlled mode (the consumer owns the toggle): pass mode/onModeChange
// as render props, or hand hunks in per render:
Diff({ mode: 'unified', hunks })
// 2. Hunks in the native WorkspaceDiffHunk shape:
const hunks = ctx.diffView.hunksOf(oldText, newText)
// [{ oldStart, oldLines, newStart, newLines, lines: [' ctx', '-old', '+new'] }]
// 3. The raw engine, for custom layouts:
const rows = ctx.diffView.engine.alignedEditRowsOf(beforeLines, afterLines)
// rows: [{ kind: 'same'|'replace'|'delete'|'insert', removedLine?, addedLine? }]
const spans = ctx.diffView.engine.wordSpansOfLinePair(beforeLine, afterLine)
// spans: { removedSpans, addedSpans }: arrays of { text, changed }
ctx.diffView.engine.wordSpanElements(spans.removedSpans, 'ddv-w-del')
Contract
- Hunks follow the native
WorkspaceDiffHunk shape, plus one extension:
unnumbered: true draws no header and no numbers, for changes whose true
position is unknown. Never lying numbers.
- Multiple hunks render as ONE continuous file view: when consecutive hunks
skip lines, a gap row ("⋯ 16 unchanged lines ⋯") stands in for the hidden
region, and a leading gap appears when the first change starts deep in the
file. Gaps need true coordinates, so they never render beside an
unnumbered hunk.
- Line numbers come from the diff itself, before any collapse, so they stay
true across hunk boundaries.
- Syntax highlighting reuses the
useCodeHighlighter /
languageForPath primitives from the platform seed module, so colors match
the native review. Without a path, or without the primitives, lines render
plain. Word highlights never depend on the primitives.
- View mode is per component instance unless the consumer controls it.
- Interactive surfaces pass render props:
onLineToggle(hunkIndex, src) with
isLinePicked makes +/− rows clickable with a picked marker;
hunkExtras(hunkIndex) renders a control inside that hunk's @@ header row;
lineMark(hunkIndex, src) renders the GitHub-Desktop-style stage checkmark
column for changed lines (filled when the callback returns true);
hunkMark(hunkIndex) -> boolean with onHunkToggle(hunkIndex) renders
the section checkmark in its own column left of the line-mark column,
drawn at the section's first changed row (in split view, in whichever
pane holds that change).
- The
ddv-* stylesheet is installed once by this plugin; consumers render
no CSS of their own for diff rows.
- No persistence; no approval coupling; the host half is a stub.
How to install
Requires a DeepSeek Harness checkout and a profile, here web. The plugin
has no dependencies:
mkdir -p ~/dsh-plugins && cd ~/dsh-plugins
git clone https://github.com/joao-paulo-santos/dsh-diff-view.git
# from the harness checkout
pnpm dsh plugin --profile web add ~/dsh-plugins/dsh-diff-view
# verify the profile still composes
pnpm dsh --profile web --dump-config
Restart the harness. Plugins that inject the diffView service can now
render diffs.
Dependencies
(none)
Plugins dependent on this
- dsh-approval-diff renders its approval-card hunks with
diffFileComponent and the engine
- dsh-scratchpad powers its
mode: 'diff' pads with diffFileComponent (optional; degrades to plain text when absent)
- dsh-wo-github renders commit patches with
diffFileComponent (optional; falls back to the raw patch text)
