[ThomasK33]

Why

The goal is to handle the items still open after the #12 follow-ups and land each on main as its own PR. This one fixes the raw addon's feed.

native/README.md says the addon's feed throws TypeError("feed typed array must be Uint8Array") for a typed array that is not a Uint8Array. It throws TypeError("feed data must be a string, Buffer, or Uint8Array") for any other value. The typed-array check in TerminalWrap::Feed never ran. The IsBuffer() branch before it is true for every ArrayBufferView in Node, because napi_is_buffer accepts any view. So a Uint16Array or Float32Array was written as raw bytes, and a DataView failed with Error: Invalid argument.

What changed

• native/terminal.cc: I deleted the IsBuffer() branch in TerminalWrap::Feed. A Buffer is a Uint8Array, so the typed-array branch now handles it.
• test/terminal.test.ts: new raw-addon tests. Uint16Array, Float32Array and Uint8ClampedArray throw the typed-array TypeError. A DataView throws the generic TypeError. Buffer, Uint8Array and a Buffer slice with a byte offset still write "AB".
• native/README.md: the Verification section no longer lists the typed-array errors as untested.

Scope

Only the raw addon's feed argument check changes. src/index.ts already rejects these values before native code runs, so the public API keeps its behavior.

Blast Radius

Code that calls the raw addon directly with a non-Uint8Array typed array or a DataView now gets a TypeError. Before, it got raw bytes written or Error: Invalid argument. Package users who go through createTerminal from the package see no change.

Verification

The test commit (1727d01) fails on the unfixed code:

     × rejects a Uint16Array in the addon feed with a TypeError 5ms
     × rejects a Float32Array in the addon feed with a TypeError 1ms
     × rejects a Uint8ClampedArray in the addon feed with a TypeError 0ms
     × rejects a DataView in the addon feed with a TypeError 1ms
     ✓ writes a Buffer in the addon feed 0ms
     ✓ writes a Uint8Array in the addon feed 0ms
     ✓ writes a Buffer slice with a byte offset in the addon feed 0ms
⎯⎯⎯⎯⎯⎯⎯ Failed Tests 4 ⎯⎯⎯⎯⎯⎯⎯
 FAIL  test/terminal.test.ts > GhosttyVtTerminal > rejects a Uint16Array in the addon feed with a TypeError
 FAIL  test/terminal.test.ts > GhosttyVtTerminal > rejects a Float32Array in the addon feed with a TypeError
 FAIL  test/terminal.test.ts > GhosttyVtTerminal > rejects a Uint8ClampedArray in the addon feed with a TypeError
AssertionError: expected undefined to be an instance of TypeError
 FAIL  test/terminal.test.ts > GhosttyVtTerminal > rejects a DataView in the addon feed with a TypeError
AssertionError: expected Error: Invalid argument to be an instance of TypeError
      Tests  4 failed | 3 passed | 33 skipped (40)

With the fix (fabeeaf):

 ✓ test/terminal.test.ts (40 tests | 33 skipped) 5ms
      Tests  7 passed | 33 skipped (40)

Repro script (node repro-feed.mjs after npm run build), after the fix. On main the raw Uint16Array, Float32Array and Uint8ClampedArray cases returned "ok", and DataView threw Error: Invalid argument.

raw feed(Buffer 'AB'): ok, text "AB"
raw feed(Uint8Array [65,66]): ok, text "AB"
raw feed(Uint16Array [0x4241]): TypeError: feed typed array must be Uint8Array
raw feed(Float32Array [1]): TypeError: feed typed array must be Uint8Array
raw feed(Uint8ClampedArray [65,66]): TypeError: feed typed array must be Uint8Array
raw feed(DataView(2 bytes 'AB')): TypeError: feed data must be a string, Buffer, or Uint8Array
public feed(Buffer 'AB'): ok, text "AB"
public feed(Uint8Array [65,66]): ok, text "AB"
public feed(Uint16Array [0x4241]): TypeError: feed data must be a string, Buffer, or Uint8Array
public feed(Float32Array [1]): TypeError: feed data must be a string, Buffer, or Uint8Array
public feed(Uint8ClampedArray [65,66]): TypeError: feed data must be a string, Buffer, or Uint8Array
public feed(DataView(2 bytes 'AB')): TypeError: feed data must be a string, Buffer, or Uint8Array

Gates, each exit 0:

1. npm ci && LIBGHOSTTY_VT_PREFIX=<ReleaseFast> npm run build:native && npm run build && npm run verify: 84 tests passed.
2. The same with the ReleaseSafe prefix: 84 tests passed.
3. UBSan: rm -rf dist && LIBGHOSTTY_VT_PREFIX=<ReleaseFast> CXXFLAGS="-fsanitize=undefined,float-cast-overflow -fno-sanitize-recover=all" LDFLAGS="-fsanitize=undefined,float-cast-overflow" npm run build:native && npm test && npm run smoke: 84 tests passed, smoke passed.
4. .agents/skills/verify-native-lifecycle/run.sh: OK: every result matches EXPECT.

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[ThomasK33]

Verdict: PASS
Head: fabeeaf

Parent: 9f8ec06 (merge base with main). Node v26.12.1 inside npm scripts (Path unset, nodedir 26.12.1), prebuilt libghostty-vt at Ghostty 83fb956.

Scenario 1: repro script. Command: node repro-feed.mjs from the checkout root after npm run build (ReleaseFast).

• Parent: raw Uint16Array gave ok, text "AB", raw Float32Array gave ok, text "\ufffd?", raw Uint8ClampedArray gave ok, text "AB", raw DataView gave Error: Invalid argument.
• Head: the three raw typed arrays give TypeError: feed typed array must be Uint8Array. Raw DataView gives TypeError: feed data must be a string, Buffer, or Uint8Array.
• diff parent vs head shows only those 4 raw lines. The raw Buffer and Uint8Array lines (ok, text "AB") and all 6 public lines are identical.

Scenario 2: byte input, raw addon and public API. A local probe ran 34 inputs through both surfaces (68 lines) and printed the visible text, the cursor, or the error. diff parent vs head shows 2 lines, both rejected typed arrays:

< raw feed(BigUint64Array [1n]): ok text="\n" cursor=0,0
< raw feed(Int8Array [65,66]): ok text="AB\n" cursor=0,2
> raw feed(BigUint64Array [1n]): TypeError: feed typed array must be Uint8Array
> raw feed(Int8Array [65,66]): TypeError: feed typed array must be Uint8Array

• Identical at parent and head on both surfaces: Buffer.alloc(4,'ABCD'), Buffer.from (ASCII, UTF-8 with an emoji, SGR, CRLF), 4 pooled Buffer.allocUnsafe(5) (byteOffset 15072 to 15096 in a 65600-byte pool), subarray at offsets 1, 3 and 5, a Uint8Array subarray, Buffer.concat, and strings.
• Empty Buffer.alloc(0), empty Uint8Array(0), an empty subarray(1,1) and a view over a detached buffer, each fed after "AB": text "AB\n", cursor 0,2, so no write.
• 1 MiB Buffer of printable text at 80x24: visible text equals an independently computed wrap of the last 1856 bytes (24 rows) and equals the string feed, at parent and head. The same holds for a 1 MiB Uint8Array at byte offset 3.
• new Uint8Array(arrayBuffer, 2, 5) next to a Uint16Array over the same buffer gives HELLO. new Uint8Array(sharedArrayBuffer, 3, 6) gives SHARED.
• Non-views keep their error: ArrayBuffer, [65,66], 65, null, undefined and {length:2} throw TypeError: feed data must be a string, Buffer, or Uint8Array.
• The same probe and the repro on the UBSan build at head print the same output as the ReleaseFast head.

Gates at head (each exit 0):

• ReleaseFast: npm ci && LIBGHOSTTY_VT_PREFIX=<fast> npm run build:native && npm run build && npm run verify: 6 files, 84 passed, smoke passed.
• ReleaseSafe (addon contains reached unreachable code: 1): same command, 84 passed, smoke passed.
• UBSan: rm -rf dist && LIBGHOSTTY_VT_PREFIX=<fast> CXXFLAGS="-fsanitize=undefined,float-cast-overflow -fno-sanitize-recover=all" LDFLAGS="-fsanitize=undefined,float-cast-overflow" npm run build:native && npm test && npm run smoke: 84 passed, smoke passed. nm -u shows __ubsan_handle_*_abort refs in terminal.o (7), addon.o (4) and libghostty_vt_shim.o (3).
• .agents/skills/verify-native-lifecycle/run.sh: OK: every result matches EXPECT.

Diff review (gh pr diff 49):

• 3 files. native/terminal.cc deletes only the IsBuffer() branch. test/terminal.test.ts adds 7 raw-addon cases. native/README.md drops "the typed-array errors" from the untested list. No other change.
• Revert test: at the head, with native/terminal.cc from the parent and the addon rebuilt, npx vitest run test/terminal.test.ts -t "addon feed" gives 4 failed | 3 passed | 33 skipped (40). The failures are the Uint16Array, Float32Array and Uint8ClampedArray cases (expected undefined to be an instance of TypeError) and DataView (expected Error: Invalid argument to be an instance of TypeError). With the head file restored: 7 passed | 33 skipped (40). The 3 "writes" cases guard Buffer input after the branch removal, so they pass at both by design.
• native/README.md line 52 (the feed error contract) now matches what the head does.

Observation (same at parent and head, not caused by this PR): a Uint8Array from another vm realm writes through the raw addon, but public feed rejects it, because src/index.ts:assertFeedData uses instanceof Uint8Array.

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