harn-cli 0.10.47

CLI for the Harn programming language — run, test, REPL, format, and lint
Documentation
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use harn_serve::adapters::acp::{
    ACP_PROMPT_ERROR_DATA_SCHEMA, ACP_SCHEMA_COMPATIBILITY, HARN_AGENT_EVENT_KINDS,
    HARN_AGENT_EVENT_METHOD, HARN_CONTENT_EXTENSION_FIELDS, HARN_PROMPT_RESULT_EXTENSION_FIELDS,
    HARN_PROVIDER_CATALOG_METHOD, HARN_SESSION_UPDATE_EXTENSIONS,
    HARN_TOOL_LIFECYCLE_EXTENSION_FIELDS,
};

use super::constants::*;
use super::support::*;
use super::values::*;

/// Emit the Rust binding.
///
/// Downstream hosts vendor this module verbatim. It carries both the canonical
/// wire-name vocabulary and serde DTOs for the permission and agent-event
/// paths, where a hand-maintained parallel shape would otherwise drift.
#[cfg(test)]
pub(super) fn generate_rust() -> String {
    generate_rust_for_version(env!("CARGO_PKG_VERSION"))
}

pub(super) fn generate_rust_for_version(artifact_version: &str) -> String {
    let mut out = String::new();
    out.push_str("// GENERATED by `harn dump-protocol-artifacts` - do not edit by hand.\n");
    out.push_str("// Source: Harn adapter schemas and Rust wire vocabulary.\n\n");
    out.push_str("//! Rust bindings for Harn's host/integrator protocol surface.\n");
    out.push_str("//!\n");
    out.push_str("//! Mirrors the TypeScript, Swift, Python, and Go artifacts generated\n");
    out.push_str("//! alongside this module. Constants carry literal JSON wire strings, while\n");
    out.push_str("//! serde DTOs own the canonical ACP permission and Harn agent-event shapes.\n");
    out.push_str("//! Adding a wire value or optional field is minor-version compatible.\n");
    out.push_str("#![allow(dead_code)]\n\n");
    out.push_str("use serde::{Deserialize, Deserializer, Serialize, Serializer};\n");
    out.push_str("use serde_json::{Map, Value};\n\n");

    out.push_str("/// Harn release that generated this binding.\n");
    out.push_str(&format!(
        "pub const HARN_PROTOCOL_ARTIFACT_VERSION: &str = {};\n\n",
        json_string_literal(artifact_version)
    ));
    out.push_str("/// Upstream ACP schema version Harn tracks.\n");
    out.push_str(&format!(
        "pub const ACP_SCHEMA_COMPATIBILITY: &str = {};\n\n",
        json_string_literal(ACP_SCHEMA_COMPATIBILITY)
    ));
    out.push_str("/// JSON-RPC method for `_harn/agentEvent` extension notifications.\n");
    out.push_str(&format!(
        "pub const HARN_AGENT_EVENT_METHOD: &str = {};\n\n",
        json_string_literal(HARN_AGENT_EVENT_METHOD)
    ));
    out.push_str("/// JSON-RPC method for Harn's provider catalog extension.\n");
    out.push_str(&format!(
        "pub const HARN_PROVIDER_CATALOG_METHOD: &str = {};\n\n",
        json_string_literal(HARN_PROVIDER_CATALOG_METHOD)
    ));
    out.push_str("/// Schema discriminator for typed `session/prompt` JSON-RPC error data.\n");
    out.push_str(&format!(
        "pub const ACP_PROMPT_ERROR_DATA_SCHEMA: &str = {};\n\n",
        json_string_literal(ACP_PROMPT_ERROR_DATA_SCHEMA)
    ));
    out.push_str(&rust_wire_types());

    out.push_str(&rust_const_group(
        "ACP_AGENT_METHOD",
        "ACP_AGENT_METHODS",
        "Stable host-facing ACP agent methods (matches the TypeScript/Swift/Python/Go bindings).",
        ACP_AGENT_METHODS,
    ));
    out.push_str(&rust_const_group(
        "ACP_DISPATCHED_METHOD",
        "ACP_DISPATCHED_METHODS",
        "Every JSON-RPC method the ACP adapter actually dispatches, including the \
         workspace-management, workflow-control, and HITL methods the stable \
         bindings do not yet expose as typed enums. Reconciled against the \
         `match` arms in `harn-serve`'s ACP adapter.",
        ACP_DISPATCHED_METHODS,
    ));
    out.push_str(&rust_const_group(
        "ACP_TRANSPORT_CONTROL_METHOD",
        "ACP_TRANSPORT_CONTROL_METHODS",
        "ACP control frames consumed by the transport before regular adapter \
         dispatch.",
        ACP_TRANSPORT_CONTROL_METHODS,
    ));
    let handled_methods =
        concat_unique_wire_values(&[ACP_TRANSPORT_CONTROL_METHODS, ACP_DISPATCHED_METHODS]);
    out.push_str(&rust_const_group_owned(
        "ACP_HANDLED_METHOD",
        "ACP_HANDLED_METHODS",
        "Every inbound ACP method Harn handles, whether by transport preemption \
         or regular adapter dispatch.",
        &handled_methods,
    ));
    out.push_str(&rust_const_group(
        "ACP_CLIENT_METHOD",
        "ACP_CLIENT_METHODS",
        "ACP client methods the agent calls back into the host for.",
        ACP_CLIENT_METHODS,
    ));
    out.push_str(&rust_const_group(
        "HARN_SESSION_TIMELINE_METHOD",
        "HARN_SESSION_TIMELINE_METHODS",
        "Session-timeline extension methods Harn accepts or emits.",
        HARN_SESSION_TIMELINE_METHODS,
    ));
    out.push_str(&rust_const_group(
        "ACP_AGENT_NOTIFICATION",
        "ACP_AGENT_NOTIFICATIONS",
        "ACP notifications the agent emits to the host.",
        ACP_AGENT_NOTIFICATIONS,
    ));

    let session_updates = all_acp_session_updates();
    out.push_str(&rust_const_group_owned(
        "ACP_SESSION_UPDATE",
        "ACP_SESSION_UPDATES",
        "Every `session/update` discriminator Harn emits (canonical ACP variants \
         plus Harn extensions), the union the Swift binding exposes as \
         `acpSessionUpdateExtensions` merged with the base ACP set.",
        &session_updates,
    ));
    out.push_str(&rust_const_group(
        "HARN_ACP_SESSION_UPDATE_EXTENSION",
        "HARN_ACP_SESSION_UPDATE_EXTENSIONS",
        "Harn-specific `session/update` discriminators beyond the canonical ACP \
         set (the values Swift publishes as `acpSessionUpdateExtensions`).",
        HARN_SESSION_UPDATE_EXTENSIONS,
    ));
    out.push_str(&rust_const_group(
        "HARN_AGENT_EVENT_KIND",
        "HARN_AGENT_EVENT_KINDS",
        "Pipeline-loop milestone kinds emitted via `_harn/agentEvent`.",
        HARN_AGENT_EVENT_KINDS,
    ));
    out.push_str(&rust_const_group_owned(
        "AGENT_TERMINAL_CLASS",
        "AGENT_TERMINAL_CLASSES",
        "Stable terminal classes carried by typed ACP prompt-error data.",
        &agent_terminal_class_values(),
    ));
    out.push_str(&rust_const_group_owned(
        "AGENT_TERMINAL_KIND",
        "AGENT_TERMINAL_KINDS",
        "Producer-owned agent terminal outcome kinds.",
        &agent_terminal_kind_values(),
    ));
    out.push_str(&rust_const_group_owned(
        "AGENT_TERMINAL_OWNER",
        "AGENT_TERMINAL_OWNERS",
        "Owners attributed by producer-owned agent terminal outcomes.",
        &agent_terminal_owner_values(),
    ));
    out.push_str(&rust_const_group(
        "HARN_PROMPT_RESULT_EXTENSION_FIELD",
        "HARN_PROMPT_RESULT_EXTENSION_FIELDS",
        "`_meta.harn` extension keys on successful ACP prompt results.",
        HARN_PROMPT_RESULT_EXTENSION_FIELDS,
    ));
    out.push_str(&rust_const_group(
        "HARN_CONTENT_EXTENSION_FIELD",
        "HARN_CONTENT_EXTENSION_FIELDS",
        "`_meta.harn` extension keys Harn attaches to ACP content.",
        HARN_CONTENT_EXTENSION_FIELDS,
    ));
    out.push_str(&rust_const_group(
        "HARN_TOOL_LIFECYCLE_EXTENSION_FIELD",
        "HARN_TOOL_LIFECYCLE_EXTENSION_FIELDS",
        "`_meta.harn` tool-lifecycle extension keys on tool_call / \
         tool_call_update notifications.",
        HARN_TOOL_LIFECYCLE_EXTENSION_FIELDS,
    ));

    out
}

fn rust_wire_types() -> String {
    let mut out = String::from(
        r#"/// Author identity on a collaborative plan revision or comment.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanAuthor {
    pub id: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub display_name: Option<String>,
}

/// Source identity for an immutable plan revision.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanSource {
    pub kind: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub uri: Option<String>,
}

/// Closed collaborative plan-comment lifecycle.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
pub enum HarnPlanCommentState {
    Open,
    Addressed,
    Resolved,
    Reopened,
}

/// Closed executable-plan approval lifecycle.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
pub enum HarnPlanApprovalState {
    Unrequested,
    Requested,
    Approved,
    Rejected,
}

/// One normalized executable plan step.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanStep {
    pub id: String,
    pub content: String,
    pub status: String,
    pub priority: Option<Value>,
}

/// Typed approval state for an executable plan.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanApproval {
    pub state: HarnPlanApprovalState,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub request_id: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub reviewer: Option<String>,
    #[serde(default, skip_serializing_if = "Vec::is_empty")]
    pub reviewers: Vec<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub approved_at: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub reason: Option<String>,
}

/// Normalized executable plan embedded in a collaborative revision.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanArtifact {
    #[serde(rename = "_type")]
    pub type_name: String,
    pub schema_version: String,
    pub id: String,
    pub tool: String,
    pub title: String,
    pub summary: String,
    pub steps: Vec<HarnPlanStep>,
    pub assumptions: Vec<String>,
    pub open_questions: Vec<String>,
    pub verification_commands: Vec<String>,
    pub approval: HarnPlanApproval,
}

/// Typed mutation that produced an immutable plan revision.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(tag = "kind", rename_all = "snake_case")]
pub enum HarnPlanRevisionOperation {
    Create { event_id: String },
    Edit { event_id: String },
    Comment { event_id: String, comment_id: String },
    CommentState {
        event_id: String,
        comment_id: String,
        state: HarnPlanCommentState,
    },
}

/// Immutable collaborative plan revision.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanRevision {
    pub revision_id: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub parent_revision_id: Option<String>,
    pub markdown: String,
    pub plan: HarnPlanArtifact,
    pub author: HarnPlanAuthor,
    pub source: HarnPlanSource,
    pub created_at: String,
    pub operation: HarnPlanRevisionOperation,
}

/// UTF-8 byte range fallback for a plan-comment anchor.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanTextRange {
    pub start: usize,
    pub end: usize,
}

/// Stable-step and quoted-text/range anchor for a plan comment.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanCommentAnchor {
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub step_id: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub quoted_text: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub range: Option<HarnPlanTextRange>,
}

/// Anchored collaborative plan comment.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanComment {
    pub comment_id: String,
    pub anchor: HarnPlanCommentAnchor,
    pub body: String,
    pub state: HarnPlanCommentState,
    pub author: HarnPlanAuthor,
    pub created_at: String,
    pub updated_at: String,
}

/// Receipt binding a comment resolution to input/output revisions and an agent event.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanCommentResolutionReceipt {
    pub receipt_id: String,
    pub comment_id: String,
    pub input_revision_id: String,
    pub output_revision_id: String,
    pub agent_run_id: String,
    pub event_id: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub explanation: Option<String>,
    pub created_at: String,
}

/// Harn's canonical collaborative plan-document contract.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnPlanDocument {
    #[serde(rename = "_type")]
    pub type_name: String,
    pub schema_version: String,
    pub document_id: String,
    pub current_revision: HarnPlanRevision,
    pub comments: Vec<HarnPlanComment>,
    pub resolution_receipts: Vec<HarnPlanCommentResolutionReceipt>,
    pub created_at: String,
    pub updated_at: String,
}

/// Closed ACP permission-option vocabulary.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
pub enum ACPPermissionOptionKind {
    AllowOnce,
    AllowAlways,
    RejectOnce,
    RejectAlways,
}

/// One option offered by `session/request_permission`.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct ACPPermissionOption {
    pub option_id: String,
    pub name: String,
    pub kind: ACPPermissionOptionKind,
}

/// Canonical ACP tool-call fields carried by a permission request.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct ACPPermissionToolCall {
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub session_update: Option<String>,
    pub tool_call_id: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub title: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub kind: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub content: Option<Vec<Value>>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub raw_input: Option<Value>,
    #[serde(default, rename = "_meta", skip_serializing_if = "Option::is_none")]
    pub meta: Option<Value>,
}

/// Params for the ACP `session/request_permission` client request.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct ACPSessionRequestPermissionParams {
    pub session_id: String,
    pub tool_call: ACPPermissionToolCall,
    pub options: Vec<ACPPermissionOption>,
}

/// User decision returned to an ACP permission request.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(tag = "outcome", rename_all = "snake_case")]
pub enum ACPPermissionOutcome {
    Selected {
        #[serde(rename = "optionId")]
        option_id: String,
    },
    Cancelled,
}

/// Result envelope for an ACP `session/request_permission` client request.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct ACPSessionRequestPermissionResult {
    pub outcome: ACPPermissionOutcome,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub reason: Option<String>,
}

/// Harn agent-event discriminator.
///
/// Unknown values remain lossless so older clients can ignore newly added
/// events while still proxying or recording the original notification.
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum HarnAgentEventKind {
"#,
    );
    for value in HARN_AGENT_EVENT_KINDS {
        out.push_str("    ");
        out.push_str(&rust_type_name(value));
        out.push_str(",\n");
    }
    out.push_str("    Other(String),\n}\n\n");

    out.push_str("impl HarnAgentEventKind {\n");
    out.push_str("    pub fn as_str(&self) -> &str {\n");
    out.push_str("        match self {\n");
    for value in HARN_AGENT_EVENT_KINDS {
        out.push_str("            Self::");
        out.push_str(&rust_type_name(value));
        out.push_str(" => ");
        out.push_str(&json_string_literal(value));
        out.push_str(",\n");
    }
    out.push_str("            Self::Other(value) => value,\n");
    out.push_str("        }\n");
    out.push_str("    }\n");
    out.push_str("}\n\n");

    out.push_str(
        r"impl Serialize for HarnAgentEventKind {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        serializer.serialize_str(self.as_str())
    }
}

impl<'de> Deserialize<'de> for HarnAgentEventKind {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: Deserializer<'de>,
    {
        let value = String::deserialize(deserializer)?;
        Ok(match value.as_str() {
",
    );
    for value in HARN_AGENT_EVENT_KINDS {
        out.push_str("            ");
        out.push_str(&json_string_literal(value));
        out.push_str(" => Self::");
        out.push_str(&rust_type_name(value));
        out.push_str(",\n");
    }
    out.push_str("            _ => Self::Other(value),\n");
    out.push_str("        })\n");
    out.push_str("    }\n");
    out.push_str("}\n\n");

    out.push_str(
        r#"/// Params carried by a `_harn/agentEvent` notification.
///
/// `sessionId` and `kind` are stable. Kind-specific fields stay flattened so
/// the generated binding round-trips every current and future event payload.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct HarnAgentEventParams {
    pub session_id: String,
    pub kind: HarnAgentEventKind,
    #[serde(default, flatten)]
    pub fields: Map<String, Value>,
}

/// JSON-RPC envelope for `_harn/agentEvent`.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct HarnAgentEventNotification {
    pub jsonrpc: String,
    pub method: String,
    pub params: HarnAgentEventParams,
    #[serde(default, flatten)]
    pub fields: Map<String, Value>,
}

"#,
    );
    out
}

/// Render a `pub const` per wire value plus a published slice of all of them.
pub(super) fn rust_const_group(
    const_prefix: &str,
    slice_name: &str,
    doc: &str,
    values: &[&str],
) -> String {
    rust_const_group_owned(const_prefix, slice_name, doc, &strs_to_strings(values))
}

pub(super) fn rust_const_group_owned(
    const_prefix: &str,
    slice_name: &str,
    doc: &str,
    values: &[String],
) -> String {
    let mut out = String::new();
    for value in values {
        out.push_str(&format!(
            "pub const {}: &str = {};\n",
            rust_const_name(const_prefix, value),
            json_string_literal(value)
        ));
    }
    out.push('\n');
    out.push_str(&rust_doc_comment(doc));
    out.push_str(&format!("pub const {slice_name}: &[&str] = &[\n"));
    for value in values {
        out.push_str("    ");
        out.push_str(&json_string_literal(value));
        out.push_str(",\n");
    }
    out.push_str("];\n\n");
    out
}

/// Build a valid SCREAMING_SNAKE_CASE Rust const identifier from a wire value.
///
/// Wire values carry `/`, `.`, `-`, and `_` separators (e.g. `session/prompt`,
/// `harn.hitl.respond`, `tool_call_update`); all collapse to `_`, runs are
/// merged, and a leading digit is prefixed with `_`.
pub(super) fn rust_const_name(prefix: &str, value: &str) -> String {
    let mut suffix = String::with_capacity(value.len());
    for ch in value.chars() {
        if ch.is_ascii_alphanumeric() {
            suffix.extend(ch.to_uppercase());
        } else {
            suffix.push('_');
        }
    }
    let suffix = collapse_repeated_underscores(suffix.trim_matches('_'));
    let name = if suffix.is_empty() {
        prefix.to_string()
    } else {
        format!("{prefix}_{suffix}")
    };
    if name.chars().next().is_some_and(|ch| ch.is_ascii_digit()) {
        format!("_{name}")
    } else {
        name
    }
}

pub(super) fn rust_type_name(value: &str) -> String {
    let mut out = String::new();
    let mut capitalize = true;
    for ch in value.chars() {
        if ch.is_ascii_alphanumeric() {
            if capitalize {
                out.extend(ch.to_uppercase());
            } else {
                out.push(ch);
            }
            capitalize = false;
        } else {
            capitalize = true;
        }
    }
    if out.chars().next().is_some_and(|ch| ch.is_ascii_digit()) {
        out.insert(0, '_');
    }
    out
}

pub(super) fn rust_doc_comment(doc: &str) -> String {
    let mut out = String::new();
    // Collapse the whitespace that Rust string continuations introduce so the
    // emitted doc comment is a single tidy line.
    let normalized = doc.split_whitespace().collect::<Vec<_>>().join(" ");
    out.push_str("/// ");
    out.push_str(&normalized);
    out.push('\n');
    out
}