fix(vscode): keep binary diffs collapsed

.changeset/quiet-binary-diffs.md

@@ -0,0 +1,5 @@
+---
+"kilo-code": patch
+---
+
+Keep binary and audio files collapsed in diff reviews instead of showing empty diff panels.

packages/kilo-vscode/src/agent-manager/local-diff.ts

@@ -1,5 +1,6 @@
 import * as fs from "fs/promises"
 import * as path from "path"
+import { binaryFile } from "../diff/shared/binary"
 import type { GitOps } from "./GitOps"
 import type { WorktreeDiffEntry } from "./types"
 
@@ -12,6 +13,7 @@ type Meta = {
   status: Status
   tracked: boolean
   generatedLike: boolean
+  binary: boolean
   stamp: string
 }
 
@@ -118,7 +120,7 @@ async function numstat(git: GitOps, dir: string, base: string, file?: string) {
   const args = ["-c", "core.quotepath=false", "diff", "--numstat", "--no-renames", base]
   if (file) args.push("--", file)
   const result = await git.execGit(args, dir)
-  const map = new Map<string, { additions: number; deletions: number }>()
+  const map = new Map<string, { additions: number; deletions: number; binary: boolean }>()
   if (result.code !== 0) return map
   for (const line of result.stdout.trim().split("\n")) {
     if (!line) continue
@@ -130,6 +132,7 @@ async function numstat(git: GitOps, dir: string, base: string, file?: string) {
     map.set(name, {
       additions: add === "-" ? 0 : parseInt(add || "0", 10) || 0,
       deletions: del === "-" ? 0 : parseInt(del || "0", 10) || 0,
+      binary: add === "-" || del === "-",
     })
   }
   return map
@@ -179,14 +182,15 @@ async function list(git: GitOps, dir: string, anc: string, log?: Log): Promise<M
     if (!file || !code) continue
     seen.add(file)
     const status = statusFromCode(code)
-    const stat = counts.get(file) ?? { additions: 0, deletions: 0 }
+    const stat = counts.get(file) ?? { additions: 0, deletions: 0, binary: false }
     result.push({
       file,
       additions: stat.additions,
       deletions: stat.deletions,
       status,
       tracked: true,
       generatedLike: generatedLike(file),
+      binary: stat.binary,
       stamp: status === "deleted" ? `deleted:${anc}` : await statStamp(dir, file),
     })
   }
@@ -205,13 +209,15 @@ async function list(git: GitOps, dir: string, anc: string, log?: Log): Promise<M
     const full = path.join(dir, file)
     const exists = await fs.stat(full).catch(() => undefined)
     if (!exists) continue
+    const binary = await binaryFile(full)
     result.push({
       file,
-      additions: await lineCount(full),
+      additions: binary ? 0 : await lineCount(full),
       deletions: 0,
       status: "added",
       tracked: false,
       generatedLike: generatedLike(file),
+      binary,
       stamp: await statStamp(dir, file),
     })
   }
@@ -230,7 +236,7 @@ function summarize(meta: Meta): WorktreeDiffEntry {
     status: meta.status,
     tracked: meta.tracked,
     generatedLike: meta.generatedLike,
-    summarized: true,
+    summarized: !meta.binary,
     stamp: meta.stamp,
   }
 }
@@ -254,13 +260,15 @@ async function detailMeta(git: GitOps, dir: string, anc: string, file: string):
     const full = path.join(dir, file)
     const exists = await fs.stat(full).catch(() => undefined)
     if (!exists) return undefined
+    const binary = await binaryFile(full)
     return {
       file,
-      additions: await lineCount(full),
+      additions: binary ? 0 : await lineCount(full),
       deletions: 0,
       status: "added",
       tracked: false,
       generatedLike: generatedLike(file),
+      binary,
       stamp: await statStamp(dir, file),
     }
   }
@@ -278,7 +286,7 @@ async function detailMeta(git: GitOps, dir: string, anc: string, file: string):
   if (!code) return undefined
 
   const counts = await numstat(git, dir, anc, file)
-  const stat = counts.get(file) ?? counts.get(pathPart) ?? { additions: 0, deletions: 0 }
+  const stat = counts.get(file) ?? counts.get(pathPart) ?? { additions: 0, deletions: 0, binary: false }
   const status = statusFromCode(code)
   return {
     file: pathPart,
@@ -287,6 +295,7 @@ async function detailMeta(git: GitOps, dir: string, anc: string, file: string):
     status,
     tracked: true,
     generatedLike: generatedLike(pathPart),
+    binary: stat.binary,
     stamp: status === "deleted" ? `deleted:${anc}` : await statStamp(dir, pathPart),
   }
 }
@@ -345,6 +354,7 @@ export async function diffFile(
   if (!anc) return null
   const meta = await detailMeta(git, dir, anc, file)
   if (!meta) return null
+  if (meta.binary) return summarize(meta)
 
   // Cheap size probe before materializing content — protects the extension
   // host from OOM on huge tracked files. `git cat-file -s` returns the blob

packages/kilo-vscode/src/diff/shared/binary.ts

@@ -0,0 +1,29 @@
+import * as fs from "fs/promises"
+
+const SAMPLE_BYTES = 8_192
+
+function binary(bytes: Uint8Array): boolean {
+  if (bytes.length === 0) return false
+
+  let controls = 0
+  for (const byte of bytes) {
+    if (byte === 0) return true
+    if (byte < 9 || (byte > 13 && byte < 32)) controls++
+  }
+  return controls / bytes.length > 0.3
+}
+
+export async function binaryFile(file: string): Promise<boolean> {
+  const stat = await fs.lstat(file).catch(() => undefined)
+  if (!stat?.isFile()) return false
+
+  const handle = await fs.open(file, "r").catch(() => undefined)
+  if (!handle) return false
+  const sample = Buffer.alloc(SAMPLE_BYTES)
+  const read = await handle
+    .read(sample, 0, sample.length, 0)
+    .catch(() => undefined)
+    .finally(() => handle.close())
+  if (!read) return false
+  return binary(sample.subarray(0, read.bytesRead))
+}

packages/kilo-vscode/src/diff/sources/git-status.ts

@@ -17,6 +17,7 @@ export interface FileEntry {
   additions: number
   deletions: number
   tracked: boolean
+  binary: boolean
   stamp?: string
 }
 
@@ -35,16 +36,17 @@ export function parseNameStatus(stdout: string): { file: string; status: Status
 }
 
 /** Parse `git diff --numstat` output into a per-file `{additions, deletions}` map. */
-export function parseNumstat(stdout: string): Map<string, { additions: number; deletions: number }> {
-  const map = new Map<string, { additions: number; deletions: number }>()
+export function parseNumstat(stdout: string): Map<string, { additions: number; deletions: number; binary: boolean }> {
+  const map = new Map<string, { additions: number; deletions: number; binary: boolean }>()
   for (const line of stdout.split("\n")) {
     if (!line.trim()) continue
     const parts = line.split("\t")
     if (parts.length < 3) continue
-    const additions = parts[0] === "-" ? 0 : parseInt(parts[0]!, 10) || 0
-    const deletions = parts[1] === "-" ? 0 : parseInt(parts[1]!, 10) || 0
+    const binary = parts[0] === "-" || parts[1] === "-"
+    const additions = binary ? 0 : parseInt(parts[0]!, 10) || 0
+    const deletions = binary ? 0 : parseInt(parts[1]!, 10) || 0
     const file = parts.slice(2).join("\t")
-    if (file) map.set(file, { additions, deletions })
+    if (file) map.set(file, { additions, deletions, binary })
   }
   return map
 }
@@ -69,7 +71,8 @@ export function summarize(entry: FileEntry): DiffFile {
     status: entry.status,
     tracked: entry.tracked,
     generatedLike: generatedLike(entry.file),
-    summarized: true,
+    // Binary metadata is complete because no deferred text body exists.
+    summarized: !entry.binary,
     // Synthetic stamp keyed on the stats we actually polled: any change to
     // the file's diff produces new additions/deletions, which invalidates
     // the webview-side cached detail via mergeWorktreeDiffs. Callers can

packages/kilo-vscode/src/diff/sources/session.ts

@@ -77,6 +77,8 @@ export function toSessionDiffFile(raw: SnapshotFileDiff): DiffFile {
     status: raw.status,
     tracked: true,
     generatedLike: false,
-    summarized: raw.patch === "",
+    // A zero-stat empty patch has no text body to fetch; nonzero stats
+    // indicate a deferred large-file summary.
+    summarized: raw.patch === "" && (raw.additions !== 0 || raw.deletions !== 0),
   }
 }

packages/kilo-vscode/src/diff/sources/staged.ts

@@ -53,6 +53,7 @@ export function createStagedDiffSource(): DiffSource {
       additions: counts.get(item.file)?.additions ?? 0,
       deletions: counts.get(item.file)?.deletions ?? 0,
       tracked: true,
+      binary: counts.get(item.file)?.binary ?? false,
     }))
   }
 
@@ -80,6 +81,8 @@ export function createStagedDiffSource(): DiffSource {
       const entry = await fileEntry(git, dir, file, log)
       if (!entry) return null
 
+      if (entry.binary) return summarize(entry)
+
       const beforeBytes = entry.status === "added" ? 0 : await blobSize(git, dir, "HEAD", file)
       const afterBytes = entry.status === "deleted" ? 0 : await blobSize(git, dir, INDEX_REF, file)
       if (beforeBytes > MAX_DETAIL_BYTES || afterBytes > MAX_DETAIL_BYTES) {
@@ -147,5 +150,6 @@ async function fileEntry(
     additions: stats.get(item.file)?.additions ?? 0,
     deletions: stats.get(item.file)?.deletions ?? 0,
     tracked: true,
+    binary: stats.get(item.file)?.binary ?? false,
   }
 }

packages/kilo-vscode/src/diff/sources/unstaged.ts

@@ -3,6 +3,7 @@ import * as vscode from "vscode"
 import { GitOps } from "../../agent-manager/GitOps"
 import { generatedLike } from "../../agent-manager/local-diff"
 import { appendOutput, getWorkspaceRoot } from "../../review-utils"
+import { binaryFile } from "../shared/binary"
 import type { DiffFile } from "../types"
 import type { DiffSource, DiffSourceDescriptor, DiffSourceFetch } from "./types"
 import {
@@ -56,6 +57,7 @@ export function createUnstagedDiffSource(): DiffSource {
       additions: counts.get(item.file)?.additions ?? 0,
       deletions: counts.get(item.file)?.deletions ?? 0,
       tracked: true,
+      binary: counts.get(item.file)?.binary ?? false,
     }))
   }
 
@@ -82,6 +84,7 @@ export function createUnstagedDiffSource(): DiffSource {
         additions: 0,
         deletions: 0,
         tracked: false,
+        binary: await binaryFile(full),
         // Untracked entries always have additions/deletions = 0 (numstat
         // can't compute them without an index blob), so fold size+mtime
         // into the stamp. Editing the file changes mtime → the webview
@@ -118,6 +121,8 @@ export function createUnstagedDiffSource(): DiffSource {
       const entry = await fileEntry(git, dir, file, log)
       if (!entry) return null
 
+      if (entry.binary) return summarize(entry)
+
       const beforeBytes = !entry.tracked || entry.status === "added" ? 0 : await blobSize(git, dir, INDEX_REF, file)
       const afterBytes = entry.status === "deleted" ? 0 : await fileSize(dir, file)
       if (beforeBytes > MAX_DETAIL_BYTES || afterBytes > MAX_DETAIL_BYTES) {
@@ -191,6 +196,7 @@ async function fileEntry(
         additions: stats.get(item.file)?.additions ?? 0,
         deletions: stats.get(item.file)?.deletions ?? 0,
         tracked: true,
+        binary: stats.get(item.file)?.binary ?? false,
       }
     }
   }
@@ -215,6 +221,7 @@ async function fileEntry(
     additions: 0,
     deletions: 0,
     tracked: false,
+    binary: await binaryFile(full),
     stamp: `added:untracked:${stat.size}:${stat.mtimeMs}`,
   }
 }

packages/kilo-vscode/tests/unit/agent-manager-diff-state.test.ts

@@ -7,6 +7,8 @@ import {
   eagerDiffFiles,
   expandableOpenFiles,
   initialOpenFiles,
+  isDiffExpandable,
+  sanitizeOpenFiles,
   toggleOpenFiles,
 } from "../../webview-ui/diff-viewer/diff-open-policy"
 import type { WorktreeFileDiff } from "../../webview-ui/src/types/messages"
@@ -72,6 +74,7 @@ describe("agent manager diff state", () => {
       initialOpenFiles([
         diff({ file: "src/app.ts", generatedLike: false, additions: 3 }),
         diff({ file: "node_modules/pkg/index.js", generatedLike: true, additions: 3 }),
+        diff({ file: "audio/notification.wav", summarized: false, additions: 0 }),
         diff({ file: "src/huge.ts", additions: EXTREME_DIFF_CHANGED_LINES + 1 }),
       ]),
     ).toEqual(["src/app.ts"])
@@ -85,6 +88,7 @@ describe("agent manager diff state", () => {
       expandableOpenFiles([
         diff({ file: "src/app.ts", generatedLike: false, additions: 3 }),
         diff({ file: "src/generated.ts", generatedLike: true, additions: 3 }),
+        diff({ file: "assets/archive.zip", summarized: false, additions: 0 }),
         diff({ file: "src/huge.ts", additions: EXTREME_DIFF_CHANGED_LINES + 1 }),
       ]),
     ).toEqual(["src/app.ts"])
@@ -95,6 +99,7 @@ describe("agent manager diff state", () => {
       diff({ file: "src/app.ts" }),
       diff({ file: "src/panel.ts" }),
       diff({ file: "src/generated.ts", generatedLike: true }),
+      diff({ file: "audio/alert.mp3", summarized: false, additions: 0 }),
       diff({ file: "src/huge.ts", additions: EXTREME_DIFF_CHANGED_LINES + 1 }),
     ]
 
@@ -109,6 +114,15 @@ describe("agent manager diff state", () => {
     expect(toggleOpenFiles(diffs, ["src/app.ts"])).toEqual(["src/app.ts", "src/panel.ts"])
     expect(toggleOpenFiles(diffs, ["src/app.ts", "src/panel.ts"])).toEqual([])
   })
+
+  it("prevents non-text diffs from entering open state", () => {
+    const audio = diff({ file: "audio/alert.wav", summarized: false, additions: 0 })
+    const text = diff({ file: "src/app.ts" })
+
+    expect(isDiffExpandable(audio)).toBe(false)
+    expect(isDiffExpandable(text)).toBe(true)
+    expect(sanitizeOpenFiles([audio, text], [audio.file, text.file])).toEqual([text.file])
+  })
 })
 
 describe("eager diff files", () => {

packages/kilo-vscode/tests/unit/diff-session-source.test.ts

@@ -57,13 +57,20 @@ describe("createSessionDiffSource.fetch", () => {
         deletions: 0,
         status: "modified",
       },
+      {
+        file: "large.txt",
+        patch: "",
+        additions: 500,
+        deletions: 200,
+        status: "modified",
+      },
     ]
     const { fetch } = recording(raw)
     const source = createSessionDiffSource("s2", fetch, "/repo")
 
     const result = await source.fetch()
 
-    expect(result.diffs).toHaveLength(2)
+    expect(result.diffs).toHaveLength(3)
 
     const foo = result.diffs[0]!
     expect(foo.file).toBe("foo.ts")
@@ -78,9 +85,10 @@ describe("createSessionDiffSource.fetch", () => {
     expect(foo.summarized).toBe(false)
 
     const big = result.diffs[1]!
-    expect(big.summarized).toBe(true)
+    expect(big.summarized).toBe(false)
     expect(big.before).toBe("")
     expect(big.after).toBe("")
+    expect(result.diffs[2]?.summarized).toBe(true)
   })
 
   it("propagates errors from the underlying fetch", async () => {