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harn_hostlib/
lib.rs

1//! `harn-hostlib`: opt-in host builtins for code intelligence (tree-sitter,
2//! repo scanning, deterministic indexing) and tool execution (search, file
3//! I/O, git, process lifecycle, file watcher).
4//!
5//! This crate is the Rust home of two classes of optional host capabilities:
6//!
7//! 1. **Code intelligence** — `ast/`, `code_index/`, `scanner/`, `fs_watch/`.
8//! 2. **Deterministic tools** — `tools/` (search, fs, git, process).
9//!
10//! These don't belong inside `harn-vm` — pulling tree-sitter grammars,
11//! ripgrep, and `notify` into the VM would balloon the footprint of every
12//! pipeline that doesn't index host code. Instead, this crate exposes a
13//! single [`HostlibCapability`] trait. Embedders such as `harn-cli`'s ACP
14//! server) compose the modules they need via [`HostlibRegistry`] and wire
15//! the resulting builtins into the VM through [`harn_vm::Vm::register_builtin`]
16//! / [`harn_vm::Vm::register_async_builtin`].
17//!
18//! ## Status
19//!
20//! The AST, scanner, code-index, and deterministic-tool surfaces are
21//! implemented. `fs_watch/` still registers its public contract with
22//! [`HostlibError::Unimplemented`] handlers. Module names, method names,
23//! and JSON schemas under `schemas/` are the source of truth for hostlib
24//! request/response compatibility, so they must stay stable while module
25//! bodies evolve.
26
27#![deny(rust_2018_idioms)]
28#![warn(missing_docs)]
29
30#[cfg(feature = "ast")]
31pub mod ast;
32#[cfg(feature = "ast")]
33pub mod code_index;
34#[cfg(feature = "computer")]
35pub mod computer;
36pub mod embed;
37pub mod error;
38pub mod fs;
39pub mod fs_snapshot;
40pub mod fs_watch;
41pub mod host_conditions;
42pub mod host_env_custody;
43pub mod host_lease;
44pub mod host_lease_capability;
45pub mod process;
46mod process_liveness;
47pub mod sandbox;
48pub mod scanner;
49pub mod schemas;
50pub mod secret_store;
51#[cfg(feature = "terminal-session")]
52pub mod terminal_session;
53pub mod tools;
54pub mod verdict;
55
56mod json;
57mod registry;
58mod text;
59mod value_args;
60
61pub use error::HostlibError;
62pub use host_conditions::{
63    HostConditionObservation, HostConditionStatus, HostConditionsCapability,
64    HostConditionsSnapshot, HostConditionsSource, HostContentionQuestion, HostEnvironment,
65    InjectedHostConditionsSource, LocalHostConditionsSource, HOST_CONDITIONS_SCHEMA_VERSION,
66};
67pub use host_lease::{
68    HostLeaseAcquireReceipt, HostLeaseAcquireStatus, HostLeaseCargoExecutionContext,
69    HostLeaseDeferReason, HostLeaseDeferReceipt, HostLeaseError, HostLeaseExecutionContext,
70    HostLeaseHandle, HostLeaseMetadataUpdateReceipt, HostLeaseOperationKind, HostLeasePathIdentity,
71    HostLeasePriorityClass, HostLeaseProcessExit, HostLeaseReleaseReceipt, HostLeaseRenewReceipt,
72    HostLeaseRequest, HostLeaseResourceClass, HostLeaseResourceDefinition, HostLeaseResourceKey,
73    HostLeaseRunLaunchFailure, HostLeaseRunReceipt, HostLeaseRunReleaseOutcome,
74    HostLeaseRunStartFailure, HostLeaseRunState, HostLeaseState, HostLeaseStore,
75    DEFAULT_HOST_LEASE_DOMAIN, HOST_LEASE_ROOT_ENV,
76};
77pub use registry::{BuiltinRegistry, HostlibCapability, HostlibRegistry, RegisteredBuiltin};
78
79/// Convenience: build a `HostlibRegistry` populated with every capability
80/// the crate ships, register them on the supplied VM, and return the
81/// registry so callers can introspect (e.g. for schema-drift tests).
82///
83/// This is the canonical entry point for embedders that want the full
84/// hostlib surface; pick-and-choose embedders should construct
85/// [`HostlibRegistry`] directly.
86pub fn install_default(vm: &mut harn_vm::Vm) -> HostlibRegistry {
87    let mut registry = HostlibRegistry::new();
88    // The code-intelligence capabilities (`ast` + `code_index`) are only
89    // compiled when the `ast` feature is on. Lean clients that omit it get
90    // the deterministic tool surface without tree-sitter or any grammar.
91    #[cfg(feature = "ast")]
92    {
93        let code_index = code_index::CodeIndexCapability::new();
94        registry = registry
95            .with(ast::AstCapabilityWithCodeIndex::new(code_index.shared()))
96            .with(code_index);
97    }
98    registry = registry
99        .with(scanner::ScannerCapability)
100        .with(embed::EmbedCapability::default())
101        .with(fs::FsCapability)
102        .with(fs_snapshot::FsSnapshotCapability)
103        .with(fs_watch::FsWatchCapability)
104        .with(tools::ToolsCapability)
105        .with(secret_store::SecretStoreCapability)
106        .with(verdict::VerdictCapability)
107        .with(host_conditions::HostConditionsCapability::default())
108        .with(host_lease_capability::HostLeaseCapability);
109    #[cfg(feature = "terminal-session")]
110    {
111        registry = registry.with(terminal_session::TerminalSessionCapability::new());
112    }
113    // Computer use (screenshot + mouse/keyboard) is opt-in at the feature
114    // level AND default-deny at runtime: even with `computer-local` compiled,
115    // the backend is a NullBackend unless `BURIN_COMPUTER_USE_TRANSPORT` is
116    // explicitly set to `local` (or `helper`/`remote`). In the product it is
117    // gated again by an off-by-default setting. Registering the builtins is
118    // therefore harmless when unarmed — every call fails with an explanatory
119    // message until the transport is explicitly chosen.
120    #[cfg(feature = "computer")]
121    {
122        registry = registry.with(computer::ComputerUseCapability::new());
123    }
124    registry.register_into_vm(vm);
125    registry
126}