Repository Analysis

rust-lang/futures-rs

Zero-cost asynchronous programming in Rust

9.4 Low AI signal View on GitHub

Analysis Overview

This report presents the forensic synthetic code analysis of rust-lang/futures-rs, a Rust project with 5,909 GitHub stars. SynthScan v2.0 examined 47,740 lines of code across 338 source files, recording 484 pattern matches distributed across 4 syntactic categories. The overall adjusted score of 9.4 places this repository in the Low AI signal band.

The scanner applied 160+ deterministic lexical heuristics, multi-line block detectors, abstract syntax tree depth profilers, and a cross-file Jaccard similarity matrix to construct a statistically normalised synthetic code estimate. All matches are individually weighted by severity coefficient and contextual multiplier before summation, and the resulting headline score is temporally discounted to account for the repository's development history relative to the commercial emergence of large language model coding tooling (November 2022 onward).

9.4
Adjusted Score
9.4
Raw Score
100%
Time Factor
2026-08-11
Last Push
5.9K
Stars
Rust
Language
47.7K
Lines of Code
338
Files
484
Pattern Hits
2026-08-29
Scan Date
0.00
HC Hit Rate

What These Metrics Mean

Adjusted Score
Primary synthetic code indicator. Raw score normalised per 1,000 lines of code and multiplied by the temporal discount factor. This is the definitive comparative metric — use it to rank repositories by AI authorship density.
Raw Score
The unmodified sum of all severity-weighted, context-multiplied pattern match scores before temporal discounting. Reflects the absolute signal strength independent of when the repository was last active.
Time Factor
The temporal discount multiplier (0–100%) applied to the raw score. Repositories last updated before ChatGPT's launch (Nov 2022) receive a 5% factor. Full signal is only assigned to repositories active in the post-adoption era (Jan 2024+).
Pattern Hits
Total count of individual pattern matches across all files and categories. A high hit count with a low score may indicate a very large codebase with isolated AI snippets; a low count with a high score indicates dense, concentrated AI signatures.
HC Hit Rate
High+Critical pattern hits per file, averaged across the repository. This orthogonal signal catches repositories where a few files are densely packed with high-severity AI tells — a strong indicator even when the normalised score appears moderate due to codebase size.
Lines of Code / Files
Total lines and files analysed. The scanner examines 94 file extensions. These denominators are used to normalise the score, enabling fair comparison between repositories of vastly different sizes.

Score History

This chart maps the temporal evolution of the adjusted synthetic code score across successive scan runs. An upward trajectory indicates ongoing incorporation of AI-generated code or expanding LLM-assisted scaffolding; a stable or declining trajectory may reflect active human refactoring, code removal, or the adoption of stricter authorship policies. The dashed secondary line (right axis) independently tracks total raw pattern hit count, which can diverge from the normalised score when codebase size changes significantly between scans.

Severity Breakdown

Classifies detected patterns by their diagnostic confidence and structural impact. CRITICAL patterns (coefficient 10) represent definitive synthetic signatures — hallucinated imports, explicit LLM attribution metadata — virtually never produced by human authors. HIGH (5) indicates strong structural tells such as cross-file repetition or cross-linguistic idioms. MEDIUM (2) covers recognisable conversational padding and AI-specific vocabulary. LOW (1) captures subtle indicators like tautological comments and generic boilerplate that require density to carry independent signal.

CRITICAL 0HIGH 0MEDIUM 3LOW 481

Directory Score Breakdown

This horizontal bar chart decomposes the repository's raw synthetic code score by top-level directory, allowing you to pinpoint precisely which modules or components carry the highest AI authorship density. Directories with disproportionately high scores relative to their size warrant targeted manual review: concentrated AI signatures often trace back to mass-generated configuration layers, auto-ported test suites, LLM-scaffolded boilerplate classes, or entire subsystems authored under heavy copilot assistance. Use this view to prioritise your human code-review effort.

Pattern Findings

The scanner identified 484 distinct pattern matches across 4 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a statistically significant AI authorship indicator. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.

Reading the findings table: The Severity column indicates the diagnostic confidence level (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — comment-context matches receive a ×1.5 weight because LLMs systematically over-annotate. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier as dense clusters constitute far stronger evidence of synthetic authorship than isolated hits.

Over-Commented Block478 hits · 436 pts
SeverityFileLineSnippetContext
LOWfutures-task/src/waker_ref.rs21impl<'a> WakerRef<'a> {COMMENT
LOWfutures-task/src/future_obj.rs121impl<T> Future for FutureObj<'_, T> {COMMENT
LOWfutures-task/src/future_obj.rs141 /// Convert an owned instance into a (conceptually owned) fat pointer.COMMENT
LOWfutures-task/src/lib.rs21#[cfg(target_has_atomic = "ptr")]COMMENT
LOWfutures-task/src/noop_waker.rs21/// Create a new [`Waker`] which doesCOMMENT
LOWfutures-task/src/spawn.rs1use core::fmt;COMMENT
LOWfutures-task/src/spawn.rs21 /// (but not guaranteed) to accept a subsequent spawn attempt.COMMENT
LOWfutures-task/src/arc_wake.rs1use alloc::sync::Arc;COMMENT
LOWfutures-task/src/arc_wake.rs21 /// Indicates that the associated task is ready to make progress and shouldCOMMENT
LOWfutures-task/src/arc_wake.rs41 /// Executors generally maintain a queue of "ready" tasks; `wake_by_ref` should placeCOMMENT
LOWfutures/tests/no-std/src/lib.rs1#![cfg(nightly)]COMMENT
LOWfutures/src/lib.rs1//! Abstractions for asynchronous programming.COMMENT
LOWfutures/src/lib.rs21//! streams and sinks, and then spawned as independent tasks that are run toCOMMENT
LOWfutures/src/lib.rs41//! let fut_values = async {COMMENT
LOWfutures/src/lib.rs61//! let fut_values = rxCOMMENT
LOWfutures/src/lib.rs101#[doc(inline)]COMMENT
LOWfutures/src/lib.rs121pub use futures_util::lock;COMMENT
LOWfutures/src/lib.rs141#[cfg(feature = "executor")]COMMENT
LOWfutures/src/lib.rs161 //!COMMENT
LOWfutures/src/lib.rs181 //! [`spawn_local_obj`]: https://docs.rs/futures/0.3/futures/task/trait.LocalSpawn.html#tymethod.spawn_local_objCOMMENT
LOWfutures-channel/tests/oneshot.rs121 orx.close();COMMENT
LOWfutures-channel/tests/oneshot.rs141// use futures::future::Either;COMMENT
LOWfutures-channel/tests/oneshot.rs161// }COMMENT
LOWfutures-channel/tests/oneshot.rs181// // end.COMMENT
LOWfutures-channel/tests/oneshot.rs201// use std::thread;COMMENT
LOWfutures-channel/tests/oneshot.rs221// Ok(Poll::Pending)COMMENT
LOWfutures-channel/tests/oneshot.rs241// // forget the spawned future: should keep running, i.e. hitCOMMENT
LOWfutures-channel/tests/mpsc.rs141 }));COMMENT
LOWfutures-channel/tests/mpsc.rs161// // responding), but dropping it leads to observable side effectsCOMMENT
LOWfutures-channel/tests/mpsc.rs181// thread::spawn(move || {COMMENT
LOWfutures-channel/src/oneshot.rs41 /// Indicates whether this oneshot is complete yet. This is filled in bothCOMMENT
LOWfutures-channel/src/oneshot.rs61 /// Field to store the task which is blocked in `Receiver::poll`.COMMENT
LOWfutures-channel/src/oneshot.rs81/// half is a `Receiver` which implements the `Future` trait, resolving to theCOMMENT
LOWfutures-channel/src/oneshot.rs161 // destructor, but our destructor hasn't run yet so if it's set then theCOMMENT
LOWfutures-channel/src/oneshot.rs201 // 2. The receiver is being droppedCOMMENT
LOWfutures-channel/src/oneshot.rs301 // Indicate to the `Sender` that we're done, so any future calls toCOMMENT
LOWfutures-channel/src/oneshot.rs341 pub fn send(self, t: T) -> Result<(), T> {COMMENT
LOWfutures-channel/src/oneshot.rs361 /// Creates a future that resolves when this `Sender`'s correspondingCOMMENT
LOWfutures-channel/src/lib.rs1//! Asynchronous channels.COMMENT
LOWfutures-channel/src/mpsc/queue.rs21 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.COMMENT
LOWfutures-channel/src/mpsc/queue.rs101 let prev = self.head.swap(n, Ordering::AcqRel);COMMENT
LOWfutures-channel/src/mpsc/queue.rs141 loop {COMMENT
LOWfutures-channel/src/mpsc/mod.rs1//! A multi-producer, single-consumer queue for sending values acrossCOMMENT
LOWfutures-channel/src/mpsc/mod.rs21//!COMMENT
LOWfutures-channel/src/mpsc/mod.rs41// At the core, the channel uses an atomic FIFO queue for message passing. ThisCOMMENT
LOWfutures-channel/src/mpsc/mod.rs61// message that caused the sender to become parked is read out of the channel.COMMENT
LOWfutures-channel/src/mpsc/mod.rs1021 // Wake up any threads waiting as they'll see that we've closed theCOMMENT
LOWfutures-channel/src/mpsc/mod.rs1241 /// It is not recommended to call this function from inside of a future,COMMENT
LOWfutures-executor/src/thread_pool.rs21/// A general-purpose thread pool for scheduling tasks that poll futures toCOMMENT
LOWfutures-executor/src/thread_pool.rs81impl ThreadPool {COMMENT
LOWfutures-executor/src/thread_pool.rs101 /// > it is guaranteed to always succeed.COMMENT
LOWfutures-executor/src/thread_pool.rs221 /// Thread name prefix is used for generating thread names. For example, if prefix isCOMMENT
LOWfutures-executor/src/lib.rs1//! Built-in executors and related tools.COMMENT
LOWfutures-executor/src/lib.rs21//! directly. In the case of `!Send` futures, [`spawn_local_obj`] can be usedCOMMENT
LOWfutures-executor/src/lib.rs61#[cfg_attr(docsrs, doc(cfg(feature = "thread-pool")))]COMMENT
LOWfutures-executor/src/unpark_mutex.rs21// re-polling.COMMENT
LOWfutures-executor/src/enter.rs41///COMMENT
LOWfutures-executor/src/local_pool.rs21COMMENT
LOWfutures-executor/src/local_pool.rs121 LocalSpawner { incoming: Rc::downgrade(&self.incoming) }COMMENT
LOWfutures-executor/src/local_pool.rs141 }COMMENT
418 more matches not shown…
Slop Phrases2 hits · 6 pts
SeverityFileLineSnippetContext
MEDIUMfutures/tests/async_await_macros.rs348 // This test may be a bit flaky. Feel free to adjust the margins as you see fit.COMMENT
MEDIUMfutures-core/src/task/__internal/atomic_waker.rs40/// Here is a simple example providing a `Flag` that can be signalled manuallyCOMMENT
Redundant / Tautological Comments3 hits · 4 pts
SeverityFileLineSnippetContext
LOWfutures-channel/src/mpsc/mod.rs640 /// # Return valueCOMMENT
LOWfutures-channel/src/mpsc/mod.rs740 /// # Return valueCOMMENT
LOWfutures-core/src/stream.rs47 /// # Return valueCOMMENT
AI Slop Vocabulary1 hit · 3 pts
SeverityFileLineSnippetContext
MEDIUMfutures-util/src/io/line_writer.rs19/// Buffering is actually done using `BufWriter`. This class will leverage `BufWriter`COMMENT