candor-classify 0.3.0

candor's curated effect classifier (crate+path -> effect) — pure, stable Rust.
Documentation
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//! candor-classify — the curated effect classifier (crate+path -> effect), extracted to a STABLE
//! crate so both the nightly `rustc_private` lint AND a stable backend share ONE source of truth
//! (no drift). Pure string logic; no rustc internals. The effect vocabulary lives in candor-report.

use candor_report::EFFECTS;

/// Project-supplied rules, consulted only when the built-in `classify` returns None.
pub fn classify_extra(
    crate_name: &str,
    path: &str,
    extra: &[(&'static str, bool, String)],
) -> Option<&'static str> {
    for (eff, is_crate, prefix) in extra {
        let hit = if *is_crate { crate_name.starts_with(prefix.as_str()) } else { path.starts_with(prefix.as_str()) };
        if hit {
            return Some(eff);
        }
    }
    None
}

/// The exact third-party crates `classify` has effect rules for, and the crate-name
/// PREFIXES it recognizes. This is the single source of truth for "what candor knows":
/// it is emitted beside the JSON report (`<prefix>.calibrated.json`) so the Claude Code
/// receipt's coverage check reads candor's real coverage instead of a hand-copied list.
/// Keep in lockstep with `classify` below — the `calibrated_set_covers_classifier` test
/// enforces that every named crate the classifier matches appears here.
pub const CALIBRATED_CRATES: [&str; 47] = [
    // network (aws_config resolves credentials over the network on `.load()`;
    // git2 remote ops — fetch/push/connect — contact the network; async_net is smol's net layer)
    "reqwest", "isahc", "ureq", "aws_config", "git2", "tokio_tcp", "tokio_udp", "async_net",
    "async_nats", "lapin", "lettre", "tungstenite", "elasticsearch", "tonic", "rdkafka",
    // database (see DB_CRATES in classify)
    "sqlx", "rusqlite", "postgres", "tokio_postgres", "diesel", "redis", "mongodb",
    "mysql", "mysql_async", "sea_orm", "deadpool_postgres",
    // filesystem (async_fs = smol; fs_err = std::fs wrapper; tempfile; glob) / entropy /
    // subprocess (async_process = smol; duct) / env (dotenvy/dotenv) / clock (time) / log / clipboard
    "memmap2", "fs_err", "async_fs", "tempfile", "glob",
    "rand", "getrandom", "fastrand",
    "portable_pty", "async_process", "duct",
    "dotenvy", "dotenv",
    "chrono", "time", "tracing", "log", "arboard",
    // compiler diagnostic emission (a dylint lint's output) — see the Log rules in classify
    "rustc_lint", "rustc_errors",
    // raw syscalls via FFI — the syscall-name table that lights up the FFI-thin tier (nix etc.)
    "libc",
];

pub const CALIBRATED_PREFIXES: [&str; 3] = ["aws_sdk_", "aws_smithy", "cap_"];

/// Crates `classify` matches by PATH prefix rather than crate-name equality (their effectful modules
/// are recognised, e.g. `tokio::net::`/`async_std::fs::`/`mio::net::`), so they're absent from
/// `CALIBRATED_CRATES` (which the liveness test probes by crate name). The coverage check must still
/// treat them as *covered* — otherwise it would mislabel the most common async crates as blind spots.
pub const PATH_CALIBRATED_CRATES: [&str; 3] = ["tokio", "async_std", "mio"];

/// Database client crates whose execution verbs are I/O (see the DB branch in `classify`).
/// Module-level so `db_crates_are_calibrated` can enforce `DB_CRATES ⊆ CALIBRATED_CRATES`.
pub const DB_CRATES: [&str; 11] = [
    "sqlx", "rusqlite", "postgres", "tokio_postgres", "diesel", "redis", "mongodb",
    "mysql", "mysql_async", "sea_orm", "deadpool_postgres",
];

/// Classify a resolved callee by the crate it belongs to and its full path.
pub fn classify(crate_name: &str, path: &str) -> Option<&'static str> {
    if crate_name.starts_with("aws_sdk_") || crate_name.starts_with("aws_smithy") {
        // Only request dispatch is network I/O; builder setters/accessors are pure.
        if path.ends_with("::send") || path.ends_with("::send_with") {
            return Some("Net");
        }
        return None;
    }
    // aws-config resolves credentials/region on `.load()` — it reaches the IMDS metadata
    // endpoint / STS over the network (and reads ~/.aws + env). Builders (`defaults()`,
    // `SdkConfig::builder()`, `BehaviorVersion::latest()`) are pure; the `load` is the I/O.
    // (Found hardening on a real app, ebman: `builder.load().await` was classified pure.)
    if crate_name == "aws_config" {
        if path.ends_with("::load") || path.ends_with("::load_defaults") {
            return Some("Net");
        }
        return None;
    }
    // git2 (libgit2 FFI): remote operations contact the network; everything else is local
    // to the .git directory. Match the remote verbs precisely — NOT bare `::clone`, which is
    // the `Clone`-trait dup of a `Remote` handle (pure), not `Repository::clone`. (Found
    // hardening on gitui: `remote.fetch`/`remote.push` were classified network-free — a git
    // client reporting it makes no network calls.)
    if crate_name == "git2" {
        if path.ends_with("::fetch")
            || path.ends_with("::push")
            || path.ends_with("::download")
            || path.ends_with("::connect")
            || path.ends_with("::connect_auth")
            || path.ends_with("::ls")
            || path.ends_with("::upload")
        {
            return Some("Net");
        }
        return None;
    }
    // libc — raw syscalls via FFI. The FFI-thin tier (nix, and the syscall layer beneath rusqlite/git2)
    // is invisible to a name classifier unless we model libc directly: a 35-crate calibration
    // (eval/calibration) showed nix reporting ZERO library effects because every wrapper bottoms out in
    // an unrecognised `libc::*` call. Classify by syscall name, but ONLY the UNAMBIGUOUS ones — the
    // socket family is Net, path/dir syscalls are Fs, spawn/exec/wait is Exec, SysV/pipe IPC is Ipc,
    // env/clock/entropy each their own. We deliberately SKIP the generic file-descriptor ops
    // (read/write/close/lseek/dup/fcntl/ioctl/poll/select/epoll*/mmap): they operate on ANY fd — file,
    // socket, or pipe — so a fixed label would mis-categorise as often as it helps. An honest
    // no-classify (under-report) beats emitting the WRONG effect. Pure conversions (htons/inet_pton/
    // gmtime) are also skipped.
    if crate_name == "libc" {
        let f = path.rsplit("::").next().unwrap_or(path);
        // path / directory / metadata syscalls (incl. *64 and *at variants)
        const FS: &[&str] = &[
            "open", "open64", "openat", "openat2", "creat", "creat64", "stat", "stat64", "lstat",
            "lstat64", "fstatat", "fstatat64", "newfstatat", "statx", "access", "faccessat",
            "faccessat2", "mkdir", "mkdirat", "rmdir", "unlink", "unlinkat", "rename", "renameat",
            "renameat2", "link", "linkat", "symlink", "symlinkat", "readlink", "readlinkat", "chmod",
            "fchmodat", "chown", "lchown", "fchownat", "truncate", "truncate64", "ftruncate",
            "ftruncate64", "opendir", "fdopendir", "readdir", "readdir64", "readdir_r", "closedir",
            "rewinddir", "seekdir", "telldir", "scandir", "mkstemp", "mkstemps", "mkostemp", "mkdtemp",
            "mknod", "mknodat", "chdir", "fchdir", "getcwd", "get_current_dir_name", "chroot",
            "pivot_root", "statfs", "statfs64", "fstatfs", "fstatfs64", "statvfs", "fstatvfs", "mount",
            "umount", "umount2", "fsync", "fdatasync", "sync", "syncfs", "sync_file_range", "fallocate",
            "posix_fallocate", "posix_fadvise", "sendfile", "sendfile64", "copy_file_range", "flock",
            "getdents", "getdents64", "utime", "utimes", "lutimes", "futimens", "utimensat", "futimesat",
            "realpath",
        ];
        // socket family — these operate only on sockets, so Net is unambiguous (AF_UNIX domain isn't
        // visible at the call, so a Unix socket reads as Net rather than Ipc; acceptable over-general).
        const NET: &[&str] = &[
            "socket", "setsockopt", "getsockopt", "bind", "listen", "accept", "accept4", "connect",
            "shutdown", "send", "sendto", "sendmsg", "sendmmsg", "recv", "recvfrom", "recvmsg",
            "recvmmsg", "getpeername", "getsockname", "getaddrinfo", "freeaddrinfo", "getnameinfo",
        ];
        // process creation / replacement / reaping
        const EXEC: &[&str] = &[
            "fork", "vfork", "clone", "clone3", "execl", "execlp", "execle", "execv", "execvp",
            "execvpe", "execve", "execveat", "fexecve", "posix_spawn", "posix_spawnp", "system",
            "popen", "pclose", "wait", "waitpid", "wait3", "wait4", "waitid",
        ];
        // pipes / FIFOs / SysV + POSIX message queues, semaphores, shared memory; socketpair (AF_UNIX)
        const IPC: &[&str] = &[
            "pipe", "pipe2", "mkfifo", "mkfifoat", "socketpair", "msgget", "msgsnd", "msgrcv", "msgctl",
            "semget", "semop", "semtimedop", "semctl", "shmget", "shmat", "shmdt", "shmctl", "mq_open",
            "mq_send", "mq_receive", "mq_timedsend", "mq_timedreceive", "mq_close", "mq_unlink",
        ];
        const ENV: &[&str] = &["getenv", "secure_getenv", "setenv", "putenv", "unsetenv", "clearenv"];
        const CLOCK: &[&str] =
            &["time", "gettimeofday", "clock_gettime", "clock_getres", "nanosleep", "clock_nanosleep"];
        const RAND: &[&str] = &["getrandom", "getentropy", "arc4random", "arc4random_buf", "arc4random_uniform"];
        if FS.contains(&f) {
            return Some("Fs");
        }
        if NET.contains(&f) {
            return Some("Net");
        }
        if EXEC.contains(&f) {
            return Some("Exec");
        }
        if IPC.contains(&f) {
            return Some("Ipc");
        }
        if ENV.contains(&f) {
            return Some("Env");
        }
        if CLOCK.contains(&f) {
            return Some("Clock");
        }
        if RAND.contains(&f) {
            return Some("Rand");
        }
        return None;
    }
    // C-library FFI bindings: libsqlite3 (under rusqlite) and libgit2 (under git2). Like the libc tier,
    // these crates are thin Rust over a C library, so their real I/O is invisible until the C entry
    // points are named. Match by the DISTINCTIVE C function name (`sqlite3_*` / `git_*`) via the call's
    // LEAF — independent of the binding crate's alias: rusqlite calls `ffi::sqlite3_step`, git2 calls
    // `raw::git_remote_fetch`, and the nightly lint resolves the same to `libsqlite3_sys`/`libgit2_sys`;
    // all spellings share the leaf. Only the I/O-performing entry points are listed — the in-memory
    // accessors (`sqlite3_bind_*`/`sqlite3_column_*`, `git_*_oid`/strarray/options builders) stay pure,
    // so a non-listed `sqlite3_`/`git_` leaf returns None (under-report, never a wrong effect). Calibrated
    // + validated against rusqlite 0.39 / git2 0.20 source (eval/calibration).
    {
        let leaf = path.rsplit("::").next().unwrap_or(path);
        if let Some(rest) = leaf.strip_prefix("sqlite3_") {
            let _ = rest;
            // SQLite C API operations that touch the database (open/exec/step/prepare/backup/blob/wal).
            const DB: &[&str] = &[
                "sqlite3_open", "sqlite3_open_v2", "sqlite3_open16", "sqlite3_close", "sqlite3_close_v2",
                "sqlite3_exec", "sqlite3_step", "sqlite3_prepare", "sqlite3_prepare_v2",
                "sqlite3_prepare_v3", "sqlite3_prepare16", "sqlite3_prepare16_v2", "sqlite3_prepare16_v3",
                "sqlite3_get_table", "sqlite3_backup_init", "sqlite3_backup_step", "sqlite3_backup_finish",
                "sqlite3_blob_open", "sqlite3_blob_read", "sqlite3_blob_write", "sqlite3_blob_reopen",
                "sqlite3_load_extension", "sqlite3_wal_checkpoint", "sqlite3_wal_checkpoint_v2",
            ];
            return DB.contains(&leaf).then_some("Db");
        }
        if leaf.starts_with("git_") {
            // libgit2: remote/transport operations contact the network …
            const NET: &[&str] = &[
                "git_clone", "git_remote_connect", "git_remote_connect_ext", "git_remote_fetch",
                "git_remote_download", "git_remote_upload", "git_remote_push", "git_remote_ls",
            ];
            // … and repository/index/odb/checkout/ref/config operations touch the on-disk .git store.
            const FS: &[&str] = &[
                "git_repository_open", "git_repository_open_ext", "git_repository_open_bare",
                "git_repository_init", "git_repository_init_ext", "git_repository_discover",
                "git_checkout_tree", "git_checkout_head", "git_checkout_index", "git_index_read",
                "git_index_write", "git_index_write_tree", "git_index_write_tree_to",
                "git_index_add_bypath", "git_index_add_all", "git_odb_open", "git_odb_read",
                "git_odb_write", "git_odb_open_wstream", "git_odb_open_rstream",
                "git_blob_create_fromdisk", "git_blob_create_fromworkdir", "git_blob_create_from_disk",
                "git_blob_create_from_workdir", "git_blob_create_from_stream", "git_commit_create",
                "git_commit_create_v", "git_reference_create", "git_reference_set_target",
                "git_reference_delete", "git_config_open_default", "git_config_open_ondisk",
                "git_config_add_file_ondisk", "git_tag_create", "git_treebuilder_write",
                "git_packbuilder_write",
            ];
            if NET.contains(&leaf) {
                return Some("Net");
            }
            if FS.contains(&leaf) {
                return Some("Fs");
            }
            return None;
        }
        if let Some(op) = leaf.strip_prefix("SSL_") {
            // OpenSSL (libssl, under the `openssl`/`native-tls` crates, called `ffi::SSL_*`). The TLS
            // handshake and record I/O run over the peer socket -> Net. Unlike libc read/write, an SSL_*
            // op is ~always over a network BIO (the rare memory-BIO/sans-IO case is the honest exception
            // we accept). The crypto surface (EVP_*/SHA*/AES*) and pure setup (SSL_CTX_new/SSL_set_fd) are
            // NOT here; `BIO_*` is skipped (a BIO may be memory or socket). Validated vs openssl 0.9 source.
            const SSL_NET: &[&str] = &[
                "connect", "accept", "do_handshake", "read", "read_ex", "write", "write_ex", "peek",
                "peek_ex", "shutdown",
            ];
            return SSL_NET.contains(&op).then_some("Net");
        }
    }
    // HTTP clients use the same builder pattern as the AWS SDK: only the dispatch is
    // I/O. (Found by the eval: ebman's reqwest calls to the Anthropic API + webhooks
    // were silently classified network-free because reqwest wasn't recognized.)
    if crate_name == "reqwest" || crate_name == "isahc" {
        if path.ends_with("::send") || path.ends_with("::execute") {
            return Some("Net");
        }
        return None;
    }
    if crate_name == "ureq" && path.ends_with("::call") {
        return Some("Net");
    }
    // Message-queue clients fully encapsulate the socket (the underlying tokio::net lives
    // inside the crate, unseen), so a user's connect/publish/consume calls ARE the I/O
    // boundary — to a remote broker, hence Net. Match the broker round-trip verbs (snake_case
    // methods); the CamelCase option/property builders stay pure. (Found hardening on consumer
    // apps: lapin `basic_publish`/`queue_declare` and async-nats `publish`/`subscribe` were
    // classified pure — a message-queue client reporting no I/O.)
    if crate_name == "async_nats" {
        if path.ends_with("::connect")
            || path.contains("::publish")
            || path.ends_with("::subscribe")
            || path.ends_with("::queue_subscribe")
            || path.contains("::request")
            || path.ends_with("::flush")
        {
            return Some("Net");
        }
        return None;
    }
    if crate_name == "lapin" {
        if path.ends_with("::connect")
            || path.ends_with("::create_channel")
            || path.contains("::basic_")
            || path.contains("::queue_")
            || path.contains("::exchange_")
            || path.contains("::tx_")
            || path.ends_with("::confirm_select")
            || path.ends_with("::close")
        {
            return Some("Net");
        }
        return None;
    }
    // SMTP email — lettre's `Transport::send` is the network dispatch; Message building is
    // pure. (Found hardening on a lettre consumer: `mailer.send(&email)` classified pure.)
    if crate_name == "lettre" {
        if path.ends_with("::send") || path.ends_with("::send_raw") {
            return Some("Net");
        }
        return None;
    }
    // WebSockets — tungstenite (the modern successor to the old `websocket` crate). connect
    // and the socket read/write/send are network; Message constructors are pure. (Found on a
    // tungstenite consumer: connect + send + read classified pure.)
    if crate_name == "tungstenite" {
        if path.ends_with("::connect")
            || path.ends_with("::read")
            || path.ends_with("::write")
            || path.ends_with("::send")
            || path.ends_with("::close")
            || path.ends_with("::flush")
            || path.ends_with("::read_message")
            || path.ends_with("::write_message")
        {
            return Some("Net");
        }
        return None;
    }
    // elasticsearch: request builders are pure; only the `.send()` dispatch is HTTP I/O
    // (same shape as reqwest / the AWS SDK). (Found on an elasticsearch consumer.)
    if crate_name == "elasticsearch" && path.ends_with("::send") {
        return Some("Net");
    }
    // gRPC — tonic. The transport connect and the Grpc client RPC dispatch are network;
    // codecs and request/response wrappers are pure. (connect repro-confirmed on a consumer;
    // the unary/streaming RPC verbs are from the tonic::client::Grpc API.)
    if crate_name == "tonic" {
        if path.ends_with("::connect")
            || path.ends_with("::unary")
            || path.ends_with("::server_streaming")
            || path.ends_with("::client_streaming")
            || path.ends_with("::streaming")
        {
            return Some("Net");
        }
        return None;
    }
    // Kafka — rdkafka (FFI to librdkafka). Producer send + consumer poll/recv/subscribe/
    // commit are network round-trips to the brokers. (API-calibrated + unit-tested; a real
    // repro needs librdkafka/cmake, deferred.)
    if crate_name == "rdkafka" {
        if path.ends_with("::send")
            || path.ends_with("::send_result")
            || path.ends_with("::recv")
            || path.ends_with("::poll")
            || path.ends_with("::subscribe")
            || path.ends_with("::commit")
            || path.ends_with("::commit_message")
            || path.ends_with("::commit_consumer_state")
            || path.ends_with("::store_offset")
            || path.ends_with("::seek")
            || path.ends_with("::fetch_metadata")
            || path.ends_with("::fetch_watermarks")
            || path.ends_with("::flush")
        {
            return Some("Net");
        }
        return None;
    }
    // cap-std: capability-oriented std. I/O goes *through* a held capability handle
    // (Dir/Pool/Clock/...), so these calls ARE the effect. Recognising them means a
    // cap-std project's real I/O is detected and matches the capability it declared
    // (via `declared_caps`/`capstd_cap`) — conformance against unforgeable capabilities.
    if crate_name.starts_with("cap_") {
        if path.contains("::net::Unix") || path.contains("::os::") {
            return Some("Ipc");
        }
        if path.contains("::net") {
            return Some("Net");
        }
        if path.contains("::time") {
            return Some("Clock");
        }
        if path.contains("::fs") || crate_name == "cap_tempfile" || crate_name == "cap_directories" {
            return Some("Fs");
        }
        return None;
    }
    // Local IPC (Unix-domain sockets) is I/O but not *network* — keep it distinct so
    // CANDOR_NO_AMBIENT and audits don't conflate it with internet access. async-std puts its
    // Unix sockets under `os::unix::net` (mirroring std); async-net (smol's net layer) under
    // `unix`.
    if path.starts_with("tokio::net::Unix")
        || path.starts_with("std::os::unix::net")
        || path.starts_with("async_std::os::unix::net")
        || path.starts_with("async_net::unix")
    {
        return Some("Ipc");
    }
    // Raw sockets. Match the I/O *types* only — `std::net` also holds pure data types
    // (SocketAddr, IpAddr, …) whose construction must NOT be flagged.
    if path.starts_with("std::net::TcpStream")
        || path.starts_with("std::net::TcpListener")
        || path.starts_with("std::net::UdpSocket")
        || path.starts_with("tokio::net::")
    {
        return Some("Net");
    }
    // Legacy tokio 0.1 socket crates — `tokio_tcp`/`tokio_udp` are *entirely* networking
    // (no pure types to over-flag), so the whole crate is Net. (Found hardening on websocat,
    // which is still on tokio 0.1: its `tokio_tcp::TcpStream::connect` was classified
    // network-free — a network tool confidently reporting 0 Net.)
    if matches!(crate_name, "tokio_tcp" | "tokio_udp") {
        return Some("Net");
    }
    // The other async runtimes mirror tokio's module layout, and their `net` modules hold only
    // socket I/O types (the pure `SocketAddr`/`IpAddr` are re-exports that resolve to `std::net`,
    // so they're excluded by def-path). `mio` is the low-level non-blocking-socket layer under
    // tokio/others; `async_net` is smol's net crate. Closes the async-std/smol/mio gap the
    // tokio_tcp note flagged. (Calibrated by module structure — these crates ARE networking — not
    // a live repro; the TCP/UDP types are defined in-crate so the def-path prefix is exact.)
    if path.starts_with("async_std::net::")
        || path.starts_with("mio::net::")
        || crate_name == "async_net"
    {
        return Some("Net");
    }
    // Database clients. Like the AWS/HTTP builders, only the execution verbs are I/O;
    // query *construction* is pure. Best-effort across crates (tune via CANDOR_CONFIG).
    // Note: bare `::query` is deliberately omitted — it executes in postgres/rusqlite but
    // only *builds* in sqlx, so including it would false-positive sqlx's `query()` builder.
    if DB_CRATES.contains(&crate_name) {
        // Postgres / SQLite-family clients: `query`/`batch_execute`/`prepare`/etc. ARE the
        // execution (round-trips to the server). sqlx is the outlier where bare `query()`
        // only BUILDS — it keeps the narrow set below. (Found by running on a real
        // tokio-postgres app, pgman: candor had reported only 4 of ~20 DB call sites.)
        if matches!(crate_name, "postgres" | "tokio_postgres" | "deadpool_postgres" | "rusqlite") {
            const PG: [&str; 13] = [
                "::query", "::query_one", "::query_opt", "::query_raw", "::execute",
                "::batch_execute", "::simple_query", "::prepare", "::prepare_typed",
                "::copy_in", "::copy_out", "::transaction", "::connect",
            ];
            if PG.iter().any(|v| path.ends_with(v)) {
                return Some("Db");
            }
            return None;
        }
        // redis: the way redis is ACTUALLY used is the high-level `Commands`/`AsyncCommands`
        // traits (`con.get`/`set`/`hset`/`lpush`/…) — every method is a round-trip — plus
        // connection establishment. The shared VERBS below only catch the low-level
        // `cmd("GET").query(con)`, so without this a normal redis user's calls classify as
        // PURE. (Found hardening on redis-rs: a fn doing `con.get`/`set` reported no effects.)
        if crate_name == "redis"
            && (path.contains("Commands::")
                || path.contains("::get_connection")
                || path.contains("::get_async_connection")
                || path.contains("::get_multiplexed_async_connection")
                || path.contains("ConnectionManager")
                || path.ends_with("::query")
                || path.ends_with("::query_async")
                || path.ends_with("::req_command")
                || path.ends_with("::req_packed_command")
                || path.ends_with("::req_packed_commands"))
        {
            return Some("Db");
        }
        // mongodb: a document-store API with none of the SQL verbs — the user calls
        // `coll.find_one`/`insert_one`/`aggregate`/… and `Client::with_uri_str`. Without
        // these a mongodb user's calls classify PURE. (Found hardening: a fn doing
        // `find_one`+`insert_one` reported no effects.) Handle accessors (name/namespace)
        // and option/doc builders don't match these verbs, so they stay pure.
        if crate_name == "mongodb" {
            const MONGO: [&str; 27] = [
                "::with_uri_str", "::connect", "::find", "::find_one", "::insert_one",
                "::insert_many", "::update_one", "::update_many", "::delete_one",
                "::delete_many", "::replace_one", "::aggregate", "::count_documents",
                "::estimated_document_count", "::count", "::distinct", "::run_command",
                "::find_one_and_update", "::find_one_and_delete", "::find_one_and_replace",
                "::list_collections", "::list_collection_names", "::list_databases",
                "::list_database_names", "::create_collection", "::create_index", "::watch",
            ];
            if MONGO.iter().any(|v| path.ends_with(v)) {
                return Some("Db");
            }
            return None;
        }
        // mysql / mysql_async: the `query`/`exec` families + `get_conn`/`ping` execute
        // immediately — no build-then-execute split like sqlx, so matching `::query` is safe
        // here. Same DB-verb-dialect gap class as redis/mongodb; calibrated from the Queryable
        // API (unit-tested; a real-app repro is the remaining confirmation).
        if matches!(crate_name, "mysql" | "mysql_async") {
            const MY: [&str; 16] = [
                "::query", "::query_first", "::query_iter", "::query_map", "::query_fold",
                "::query_drop", "::exec", "::exec_first", "::exec_iter", "::exec_map",
                "::exec_fold", "::exec_drop", "::exec_batch", "::prep", "::ping", "::get_conn",
            ];
            if MY.iter().any(|v| path.ends_with(v)) {
                return Some("Db");
            }
            return None;
        }
        // sea_orm: an ORM whose execution is split from building (like sqlx). The query
        // BUILDERS (`Entity::find`, `Entity::insert`) are pure; execution happens at `.all`/
        // `.one`/`.count`/`.stream` and `Insert/Update/Delete::exec`. The write path via an
        // ActiveModel (`model.insert(db)`) executes too — distinguished from the `EntityTrait`
        // builder by the trait in the path (`ActiveModelTrait::`). (Found hardening on a
        // sea_orm consumer app: `.all(db)` reads and `ActiveModel::insert` writes were pure.)
        if crate_name == "sea_orm" {
            if path.ends_with("::all")
                || path.ends_with("::one")
                || path.ends_with("::count")
                || path.ends_with("::stream")
                || path.ends_with("::exec")
                || path.ends_with("::exec_with_returning")
                || path.ends_with("::exec_without_returning")
                || path.ends_with("::connect")
                || path.ends_with("::execute")
                || path.ends_with("::execute_unprepared")
                || path.ends_with("::query_one")
                || path.ends_with("::query_all")
                || path.ends_with("::fetch_page")
                || path.ends_with("::num_items")
                || path.contains("ActiveModelTrait::")
            {
                return Some("Db");
            }
            return None;
        }
        const VERBS: [&str; 16] = [
            "::execute", "::query_row", "::query_map", "::query_one", "::fetch_one",
            "::fetch_all", "::fetch_optional", "::fetch", "::connect", "::acquire",
            "::begin", "::commit", "::rollback", "::load", "::get_result", "::get_results",
        ];
        if VERBS.iter().any(|v| path.ends_with(v)) {
            return Some("Db");
        }
        return None;
    }
    // Filesystem. `tokio::fs`/`async_std::fs` are the async mirrors of `std::fs`; `async_fs` is
    // smol's fs crate; `fs_err` is a drop-in `std::fs` wrapper (its whole surface is fs I/O).
    if path.starts_with("std::fs::")
        || path.starts_with("tokio::fs::")
        || path.starts_with("async_std::fs::")
        || crate_name == "async_fs"
        || crate_name == "fs_err"
        || crate_name == "memmap2"
    {
        return Some("Fs");
    }
    // tempfile: creating a temp file/dir touches the disk. Match the create/persist verbs (the
    // `Builder` setters — prefix/suffix/rand_bytes — stay pure). `persist`/`keep` rename/retain
    // the file on disk; `close` removes it.
    if crate_name == "tempfile"
        && (path.ends_with("::tempfile")
            || path.ends_with("::tempfile_in")
            || path.ends_with("::tempdir")
            || path.ends_with("::tempdir_in")
            || path.ends_with("NamedTempFile::new")
            || path.ends_with("NamedTempFile::new_in")
            || path.ends_with("TempDir::new")
            || path.ends_with("TempDir::new_in")
            || path.ends_with("::persist")
            || path.ends_with("::persist_noclobber")
            || path.ends_with("::keep"))
    {
        return Some("Fs");
    }
    // glob: walks the filesystem to expand a pattern (the returned iterator reads directories).
    // `Pattern::matches` is pure string matching — match only the directory-walking entry points.
    if crate_name == "glob" && (path.ends_with("::glob") || path.ends_with("::glob_with")) {
        return Some("Fs");
    }
    // Randomness / entropy. `getrandom`/`fastrand` are effectful end-to-end. `rand` is NOT — it
    // mixes entropy/generation (effectful) with *pure* distribution constructors (`Uniform::new`,
    // `Normal::new`) and deterministic-seed constructors (`seed_from_u64`). Flagging the whole crate
    // over-reported those as `Rand`; match only the calls that actually consume randomness — the
    // entropy sources (`OsRng`, `thread_rng`/`rng`, `from_entropy`/`from_os_rng`) and the generation
    // verbs (`gen*`/`random*`/`fill*`/`sample*`/`next_u*`). A `Uniform::new` is now correctly pure.
    if crate_name == "getrandom" || crate_name == "fastrand" {
        return Some("Rand");
    }
    if crate_name == "rand" {
        let rng_verb = path.ends_with("::gen")
            || path.ends_with("::gen_range")
            || path.ends_with("::gen_bool")
            || path.ends_with("::gen_ratio")
            || path.ends_with("::random")
            || path.ends_with("::random_range")
            || path.ends_with("::random_bool")
            || path.ends_with("::random_ratio")
            || path.ends_with("::random_iter") // rand 0.9 iterator generator
            || path.ends_with("::gen_iter")
            || path.ends_with("::fill")
            || path.ends_with("::fill_bytes")
            || path.ends_with("::try_fill")
            || path.ends_with("::try_fill_bytes")
            || path.ends_with("::sample")
            || path.ends_with("::sample_iter")
            || path.ends_with("::next_u32")
            || path.ends_with("::next_u64")
            || path.ends_with("::thread_rng")
            || path.ends_with("::rng")
            || path.ends_with("::from_entropy")
            || path.ends_with("::from_os_rng");
        if rng_verb || path.contains("OsRng") {
            return Some("Rand");
        }
        return None;
    }
    // Subprocess spawning. `tokio::process` is the async mirror of `std::process` — it exists
    // only to spawn/control subprocesses (`Command`/`Child`, no pure data types like std's
    // `Stdio`/`ExitStatus`/`exit`), so spawning through it is Exec just the same. Without this an
    // async app's `tokio::process::Command::new(..).spawn()` classified pure — a silent under-report
    // of subprocess execution, the dangerous direction (mirrors the tokio::fs/tokio::net coverage).
    if path.starts_with("std::process::Command")
        || path.starts_with("std::process::Child")
        || path.starts_with("tokio::process::Command")
        || path.starts_with("tokio::process::Child")
        || path.starts_with("async_std::process::Command")
        || path.starts_with("async_std::process::Child")
        || crate_name == "async_process"
        || crate_name == "portable_pty"
    {
        return Some("Exec");
    }
    // duct: a subprocess-orchestration crate. `cmd()`/`cmd!` only *build* an Expression; the
    // spawn/wait happens at `run`/`read`/`start`. Match the execution verbs, not the builder.
    if crate_name == "duct"
        && (path.ends_with("::run")
            || path.ends_with("::read")
            || path.ends_with("::start")
            || path.ends_with("::read_chars"))
    {
        return Some("Exec");
    }
    if path.starts_with("std::env::") {
        return Some("Env");
    }
    // dotenvy / dotenv: load environment variables (reading a `.env` file and mutating the process
    // environment). Match the load/read entry points; `Error`/builder types stay pure.
    if matches!(crate_name, "dotenvy" | "dotenv")
        && (path.ends_with("::dotenv")
            || path.ends_with("::dotenv_override")
            || path.ends_with("::from_path")
            || path.ends_with("::from_path_override")
            || path.ends_with("::from_filename")
            || path.ends_with("::from_filename_override")
            || path.ends_with("::from_read")
            || path.ends_with("::from_read_override")
            || path.ends_with("::load")
            || path.ends_with("::var")
            || path.ends_with("::vars"))
    {
        return Some("Env");
    }
    // Wall-clock reads. Match the `now` accessor precisely (ends_with), not any path
    // containing the substring "now". The `time` crate (distinct from `std::time`/`chrono`)
    // reads the clock via `now_utc`/`now_local` (and the deprecated `Instant::now`).
    if (crate_name == "chrono" || path.starts_with("std::time::")) && path.ends_with("::now") {
        return Some("Clock");
    }
    if crate_name == "time"
        && (path.ends_with("::now_utc") || path.ends_with("::now_local") || path.ends_with("::now"))
    {
        return Some("Clock");
    }
    if crate_name == "tracing" {
        return Some("Log");
    }
    // The `log` facade: its macros route through `log::__private_api`; the crate's types
    // (`Level`, `LevelFilter`) are pure, so match the logging entry, not the whole crate.
    if crate_name == "log" && path.contains("::__private_api") {
        return Some("Log");
    }
    // Compiler diagnostic emission — the ONE genuinely effectful operation in the otherwise-pure
    // rustc_* surface (a dylint lint's actual OUTPUT: it writes warnings/errors to the compiler's
    // diagnostic sink). Classified `Log` (same family as `tracing`/`log` — program output). Match the
    // emission verbs precisely; rustc_lint/rustc_errors are mostly pure types (Lint, LintId, the Diag
    // BUILDERS), and only the terminal `emit`/`emit_span_lint` actually produces output.
    if crate_name == "rustc_lint"
        && (path.ends_with("::emit_span_lint")
            || path.ends_with("::span_lint")
            || path.ends_with("::span_lint_hir"))
    {
        return Some("Log");
    }
    if crate_name == "rustc_errors"
        && (path.ends_with("::emit")
            || path.ends_with("::emit_diagnostic")
            || path.ends_with("::emit_now"))
    {
        return Some("Log");
    }
    if crate_name == "arboard" {
        return Some("Clipboard");
    }
    None
}

pub fn cap_from_name(name: &str) -> Option<&'static str> {
    EFFECTS.iter().copied().find(|e| *e == name)
}

/// Map a cap-std capability *type* to the effect it authorises. Holding one of these
/// (e.g. `&Dir`) is the real, unforgeable right to perform that effect — so candor
/// treats it as a declared capability, exactly like its own `&Fs` token.
pub fn capstd_cap(crate_name: &str, type_name: &str) -> Option<&'static str> {
    if !crate_name.starts_with("cap_") {
        return None;
    }
    Some(match type_name {
        "Dir" => "Fs",
        "TcpListener" | "TcpStream" | "UdpSocket" | "Pool" => "Net",
        "UnixListener" | "UnixStream" | "UnixDatagram" => "Ipc",
        "SystemClock" | "MonotonicClock" => "Clock",
        _ => return None,
    })
}