PR #35559 - oven-sh/bun

Net -418 LOC across 29 files (9 crates). Every removed symbol was verified unreferenced via repo-wide rg across src/, build/debug/codegen/, and src/codegen/, then confirmed by a full bun bd build and rust:check-all (all 10 targets).

webcore

blob::Inline struct + impl (Blob.rs, ~82 LOC): never constructed. The InlineBlob body variant it was meant to back exists only as commented-out match arms throughout Body.rs and RequestContext.rs; those stale comments are removed too.
streams::Writable::is_done, streams::Signal::init, BufferAction::{resolve, get}: zero callers. BufferAction is only consumed via fulfill/reject/value/swap in ByteStream.rs.
Response::header, response::from_js_direct: zero callers. Header reads go through FetchHeaders::fast_get directly; the free-fn from_js_direct duplicated the trait method.
NewSource::{unref, start} (ReadableStream.rs): zero callers; set_ref(false) and on_start_from_js cover these.
file_reader::TAG const: readable_stream::Tag::File is referenced directly everywhere.

jsc

DeprecatedStrong::unref (~31 LOC including the stale contract comment): no ref() counterpart exists and the sole user (test_runner/Collection.rs) uses init + Drop only, as the deleted comment already noted.
strong::Optional::call, Weak::{init, has}, JSPropertyIterator::reset: zero callers.
JSString::eql + JSC__JSString__eql extern import: zero Rust callers.
URLSearchParams::create + extern import: only from_js/to_string are used.

bundler

PathTemplateConst::{print, needs} and the Display impls for both PathTemplateConst and PathTemplate (~43 LOC): every call site uses PathTemplate::print(&mut buf, ..) directly; nothing formats either type via {}.

ast

Expr::is_boolean (~23 LOC): only self-recursive. External .is_boolean() calls are on JSValue.
Log::init_comptime: zero callers.

install

ProgressStrings::extract() and its three backing consts: zero callers. EXTRACT_EMOJI (used in runTasks.rs) is kept.
bin::Context type alias: callers name PriorityQueueContext directly.
SecurityScanSubprocess::event_loop: the macro wiring bypasses it via event_loop_handle.as_event_loop_ctx().
Scripts::List::first: zero callers.

spawn

StaticPipeWriter::{get_buffer, flush, loop_, event_loop}: the impl_buffered_writer_parent! macro wires direct field access; no external caller.
ResultTask::<T>::run_from_main_thread_mini: the Mini variant has its own; this one is orphaned.

runtime/node

dir_iterator::IteratorError enum and its runtime::Error::DirIterator variant: never constructed. The iterator returns bun_sys::Error.
StatOrNotFound::to_js (identical to to_js_newly_created), Null::to_js, VectorArrayBuffer::to_js: the FsReturn impls inline the bodies and never call these.

resolver

DirInfoRef::as_ptr: the internal .as_ptr() calls go through BackRef/NonNull, not this wrapper.
Commented-out Zig stubs in fs.rs.

libarchive

ReadArchive::as_ptr, WriteArchive::as_ptr, OwnedEntry::as_ptr: every consumer uses Deref to &Archive/&Entry.

Verification

bun bd builds clean.
bun run rust:check-all: 10 ok, 0 failed (linux/macos/windows/freebsd/android, x64 + aarch64).
Smoke tests: test/js/web/fetch/blob.test.ts (46/46), test/js/web/fetch/body.test.ts + fs.test.ts stat subset pass.

No overlap with open dead-code PRs #34965, #34759, #35437. One touched file (Blob.rs) overlaps with #35399 at disjoint line ranges (that PR edits lines 605-643; this removes 6856-6937).

[review] gate passed · iteration 6 · 20 files touched

fails on main (without fix)

ASAN without fix: 4 FAILED
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/mechgate.xml" "test/internal/source-lints/dead-symbols-35559.test.ts"
bun test v1.4.0 (c5973b0d0)

test/internal/source-lints/dead-symbols-35559.test.ts:
37 |     ["src/runtime/webcore/Response.rs", /pub fn header\(&self, name: HTTPHeaderName\)/],
38 |     ["src/runtime/webcore/Response.rs", /pub fn from_js_direct\(value: JSValue\) -> Option<\*mut Response>/],
39 |     ["src/runtime/webcore/ReadableStream.rs", /pub fn unref\(&mut self\) \{\s*\n\s*if C::SUPPORTS_REF/],
40 |     ["src/runtime/webcore/FileReader.rs", /pub const TAG: readable_stream::Tag/],
41 |   ];
42 |   expect(resurrected(checks)).toEqual([]);
                                   ^
error: expect(received).toEqual(expected)

- []
+ [
+   "src/runtime/webcore/Blob.rs: pub struct Inline \{",
+   "src/runtime/webcore/Blob.rs: impl Inline \{",
+   "src/runtime/webcore/Body.rs: InlineBlob",
+   "src/runtime/server/RequestContext.rs: InlineBlob",
+   "src/runtime/webcore/streams.rs: pub fn get\(&self\) -> \*mut JSPromise \{",
+   "src/runtime/webcore/FileReader.rs: pub const TAG: readable_st
... (truncated)

release without fix: 4 FAILED
bun test v1.4.0-canary.1 (1498d7b77)

test/internal/source-lints/dead-symbols-35559.test.ts:
37 |     ["src/runtime/webcore/Response.rs", /pub fn header\(&self, name: HTTPHeaderName\)/],
38 |     ["src/runtime/webcore/Response.rs", /pub fn from_js_direct\(value: JSValue\) -> Option<\*mut Response>/],
39 |     ["src/runtime/webcore/ReadableStream.rs", /pub fn unref\(&mut self\) \{\s*\n\s*if C::SUPPORTS_REF/],
40 |     ["src/runtime/webcore/FileReader.rs", /pub const TAG: readable_stream::Tag/],
41 |   ];
42 |   expect(resurrected(checks)).toEqual([]);
                                   ^
error: expect(received).toEqual(expected)

- []
+ [
+   "src/runtime/webcore/Blob.rs: pub struct Inline \{",
+   "src/runtime/webcore/Blob.rs: impl Inline \{",
+   "src/runtime/webcore/Body.rs: InlineBlob",
+   "src/runtime/server/RequestContext.rs: InlineBlob",
+   "src/runtime/webcore/streams.rs: pub fn get\(&self\) - \*mut JSPromise \{",
+   "src/runtime/webcore/FileReader.rs: pub const TAG: readable_stream::Tag",
+ ]

- Expected  - 1
+ Received  + 8

      at <anonymous> (/workspace/bun/test/internal/source-lints/dead-symbols-35559.test.ts:42:31)
(fail) dead webcore items removed
... (truncated)

passes on PR (with fix)

ASAN with fix: all passed
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/mechgate.xml" "test/internal/source-lints/dead-symbols-35559.test.ts"
bun test v1.4.0 (c5973b0d0)

test/internal/source-lints/dead-symbols-35559.test.ts:
(pass) dead webcore items removed in #35559 do not reappear [54.79ms]
(pass) dead jsc helpers removed in #35559 do not reappear [18.66ms]
(pass) dead bundler/ast items removed in #35559 do not reappear [17.06ms]
(pass) dead install/spawn/node/resolver items removed in #35559 do not reappear [35.96ms]

 4 pass
 0 fail
 4 expect() calls
Ran 4 tests across 1 file. [2.17s]
__F:0:S:0

release with fix: all passed
$ bun scripts/build.ts --profile=release
[configured] bun-profile → bun (stripped) in 715ms (unchanged)
ninja: Entering directory `/workspace/bun/build/release'
[1/22] cxx obj/unified/UnifiedSource-src_jsc_bindings-2.cpp.o
[2/22] cxx obj/unified/UnifiedSource-src_jsc_bindings-4.cpp.o
[3/22] cxx obj/unified/UnifiedSource-src_jsc_bindings-0.cpp.o
[4/22] cxx obj/unified/UnifiedSource-src_jsc_bindings_node-0.cpp.o
[5/22] cxx obj/unified/UnifiedSource-src_jsc_bindings_webcore-3.cpp.o
[6/22] cxx obj/unified/UnifiedSource-src_jsc_bindings-3.cpp.o
[7/22] cxx obj/unified/UnifiedSource-src_jsc_bindings-1.cpp.o
[8/22] cxx obj/unified/UnifiedSource-src_jsc_bindings_webcore-4.cpp.o
[9/22] gen generated_host_exports.rs
generated_host_exports.rs: 94 exports (host=3, lazy=10, generic=81, rust=0); 239 extern-C blocks audited
[10/22] cxx obj/src/jsc/bindings/bindings.cpp.o
[11/22] gen cpp.rs (cppbind)
[11/22] cargo bun_bin → libbun_rust.a (--target x86_64-unknown-linux-gnu)

  nightly-2026-07-20-x86_64-unknown-linux-gnu unchanged - rustc 1.99.0-nightly (9f36de775 2026-07-19)

[1m[92m   Compiling[0m bun_libarchive v0.0.0 (/workspace/bun/src/libarchive)
[1m[92m   Compiling[0m
... (truncated)

diff hotspot

src/bundler/options.rs                             |  41 --------
 src/install/bin.rs                                 |   2 -
 src/jsc/DeprecatedStrong.rs                        |  41 +-------
 src/jsc/bindings/URLSearchParams.cpp               |   7 --
 src/jsc/bindings/bindings.cpp                      |   4 -
 src/jsc/bindings/headers.h                         |   1 -
 src/libarchive/lib.rs                              |  12 ---
 src/resolver/dir_info.rs                           |   3 -
 src/resolver/fs.rs                                 |   9 --
 src/runtime/error.rs                               |   3 -
 src/runtime/node/dir_iterator.rs                   |  11 ---
 src/runtime/node/node_fs.rs                        |  11 ---
 src/runtime/node/types.rs                          |   4 -
 src/runtime/server/RequestContext.rs               |   3 -
 src/runtime/webcore/Blob.rs                        |  49 ----------
 src/runtime/webcore/Body.rs                        |  25 +----
 src/runtime/webcore/FileReader.rs                  |   1 -
 src/runtime/webcore/Response.rs                    |   4 +-
 src/runtime/webcore/streams.rs                     |   4 -
 .../source-lints/dead-symbols-35559.test.ts        | 104 +++++++++++++++++++++
 20 files changed, 108 insertions(+), 231 deletions(-)

gate history · 1 passed · 1 rejected · iteration 6

evidence per changed file

file                                  reads  edits  tests
src/bundler/options.rs                    6      8      0
src/install/bin.rs                        3      3      0
src/jsc/DeprecatedStrong.rs               5      7      0
src/jsc/bindings/URLSearchParams.cpp      1      1      0
src/jsc/bindings/bindings.cpp             1      1      0
src/jsc/bindings/headers.h                1      1      0
src/libarchive/lib.rs                     3     11      0
src/resolver/dir_info.rs                  2      2      0
src/resolver/fs.rs                        1      1      0
src/runtime/error.rs                      2      2      0
src/runtime/node/dir_iterator.rs          1      1      0
src/runtime/node/node_fs.rs               3      5      0
src/runtime/node/types.rs                 1      1      0
src/runtime/server/RequestContext.rs      1      2      0
src/runtime/webcore/Blob.rs               2      2      0
src/runtime/webcore/Body.rs               4     12      0
(+ 4 more files)