repopilot 0.15.0

//! End-to-end test for the `repopilot mcp` stdio server: spawn the real binary,
//! drive it with JSON-RPC over stdin, and assert the tool surface and a local
//! tool call. The whole exchange runs offline from on-disk files, exercising the
//! local-first promise (no network, no AI service).

use serde_json::Value;
use std::fs;
use std::io::Write;
use std::path::Path;
use std::process::{Command, Stdio};

/// Runs `repopilot mcp` over `requests` (one JSON-RPC message each) and returns
/// the decoded responses in order. Closing stdin ends the server loop.
fn run_mcp(requests: &[&str], cwd: &Path) -> Vec<Value> {
    let mut child = Command::new(env!("CARGO_BIN_EXE_repopilot"))
        .arg("mcp")
        .current_dir(cwd)
        .stdin(Stdio::piped())
        .stdout(Stdio::piped())
        .stderr(Stdio::null())
        .spawn()
        .expect("spawn `repopilot mcp`");

    {
        let mut stdin = child.stdin.take().expect("child stdin");
        for request in requests {
            stdin.write_all(request.as_bytes()).expect("write request");
            stdin.write_all(b"\n").expect("write newline");
        }
        // Dropping stdin sends EOF, which ends the server's read loop.
    }

    let output = child.wait_with_output().expect("wait for `repopilot mcp`");
    assert!(
        output.status.success(),
        "server exited with {:?}",
        output.status.code()
    );

    String::from_utf8(output.stdout)
        .expect("stdout is utf-8")
        .lines()
        .filter(|line| !line.trim().is_empty())
        .map(|line| serde_json::from_str(line).expect("response line is json"))
        .collect()
}

#[test]
fn mcp_server_initializes_lists_tools_and_runs_scan_locally() {
    let temp = tempfile::tempdir().expect("temp dir");
    fs::create_dir_all(temp.path().join("src")).expect("src dir");
    fs::write(
        temp.path().join("src/lib.rs"),
        "pub fn add(a: i32, b: i32) -> i32 {\n    a + b\n}\n",
    )
    .expect("source file");

    let responses = run_mcp(
        &[
            r#"{"jsonrpc":"2.0","id":1,"method":"initialize","params":{}}"#,
            r#"{"jsonrpc":"2.0","id":2,"method":"tools/list"}"#,
            r#"{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"repopilot_scan","arguments":{"path":"."}}}"#,
        ],
        temp.path(),
    );

    assert_eq!(responses.len(), 3, "one response per request");

    // initialize advertises the server identity.
    assert_eq!(responses[0]["result"]["serverInfo"]["name"], "repopilot");

    // tools/list exposes the full tool surface in order.
    let names: Vec<&str> = responses[1]["result"]["tools"]
        .as_array()
        .expect("tools array")
        .iter()
        .map(|tool| tool["name"].as_str().expect("tool name"))
        .collect();
    assert_eq!(
        names,
        [
            "repopilot_review_change",
            "repopilot_scan",
            "repopilot_context",
            "repopilot_explain_file",
        ]
    );

    // tools/call runs the scan entirely from local files and returns a JSON report.
    let result = &responses[2]["result"];
    assert_eq!(result["isError"], false, "scan should succeed");
    let text = result["content"][0]["text"].as_str().expect("text content");
    let report: Value = serde_json::from_str(text).expect("scan report is json");
    assert!(
        report["schema_version"].is_string(),
        "scan report carries schema metadata"
    );
    assert!(report["report"].is_object(), "scan report carries findings");
}

#[test]
fn mcp_server_reports_unknown_tool_as_in_band_error() {
    let temp = tempfile::tempdir().expect("temp dir");

    let responses = run_mcp(
        &[
            r#"{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"nope","arguments":{}}}"#,
        ],
        temp.path(),
    );

    let result = &responses[0]["result"];
    assert_eq!(result["isError"], true);
    assert!(
        result["content"][0]["text"]
            .as_str()
            .expect("text")
            .contains("unknown tool")
    );
}