test(cli): wire_fetch — chunk/doc + chunk_not_found integration (fb-35)

3 lexical-only integration tests: chunk JSON shape, doc truncated
with --max-tokens, unknown chunk_id returns error.v1 with
code = chunk_not_found.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/kebab-cli/tests/common/mod.rs

@@ -196,6 +196,30 @@ pub fn run_ask_json(cfg: &Path, query: &str) -> String {
     String::from_utf8_lossy(&out.stdout).to_string()
 }
 
+/// p9-fb-35: invoke `kebab fetch` with arbitrary trailing flags,
+/// capture stdout + stderr. Caller is responsible for supplying
+/// `--json` (global flag) before the subcommand position via the
+/// `args` slice (e.g. `&["--json", "chunk", &id]`). Asserts the
+/// binary exited 0; non-zero exits fail the test with stderr
+/// included — for negative-path tests (unknown chunk_id etc.) drive
+/// the binary directly via `std::process::Command`.
+pub fn run_fetch_with_args(cfg: &Path, args: &[&str]) -> (String, String) {
+    let bin = env!("CARGO_BIN_EXE_kebab");
+    let mut cmd = Command::new(bin);
+    cmd.arg("--config").arg(cfg).arg("fetch");
+    cmd.args(args);
+    let out = cmd.output().expect("kebab fetch");
+    assert!(
+        out.status.success(),
+        "fetch failed: args={args:?} stderr={}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    (
+        String::from_utf8_lossy(&out.stdout).to_string(),
+        String::from_utf8_lossy(&out.stderr).to_string(),
+    )
+}
+
 /// Rewrite `documents.updated_at` for one workspace path to
 /// `now - days_ago` (RFC3339 UTC). Mirrors
 /// `kebab-app/tests/common/mod.rs::backdate_document_updated_at`.

crates/kebab-cli/tests/wire_fetch.rs

@@ -0,0 +1,130 @@
+//! p9-fb-35: CLI fetch wire shape + plain output + exit codes.
+//!
+//! Lexical-only — no fastembed / no Ollama. Each test builds its own
+//! TempDir KB via `common::write_config` + `common::ingest` and drives
+//! `kebab fetch` through `common::run_fetch_with_args`. Verifies:
+//!
+//! - `--json fetch chunk <id>` emits the `fetch_result.v1` wrapper
+//!   with `kind = "chunk"` and a populated `chunk` object.
+//! - `--json fetch doc <id> --max-tokens N` flips `truncated: true`
+//!   once the budget binds.
+//! - Unknown `chunk_id` exits non-zero and emits an `error.v1`
+//!   ndjson line on stderr with `code = "chunk_not_found"`.
+
+mod common;
+
+use serde_json::Value;
+use std::fs;
+
+#[test]
+fn fetch_chunk_json_emits_fetch_result_v1() {
+    let dir = tempfile::tempdir().unwrap();
+    let (cfg, workspace, _data) = common::write_config(dir.path(), 30);
+    fs::write(workspace.join("a.md"), "# T\n\napples are red.\n").unwrap();
+    common::ingest(&cfg, &workspace);
+
+    // Find chunk_id via search.
+    let (search_stdout, _) = common::run_search_with_args(
+        &cfg,
+        &["--json", "--mode", "lexical", "--k", "1", "apples"],
+    );
+    let search: Value = serde_json::from_str(search_stdout.trim())
+        .unwrap_or_else(|e| panic!("search not JSON: {search_stdout:?}: {e}"));
+    let chunk_id = search["hits"][0]["chunk_id"]
+        .as_str()
+        .expect("chunk_id on first hit")
+        .to_string();
+
+    let (stdout, _) = common::run_fetch_with_args(
+        &cfg,
+        &["--json", "chunk", &chunk_id],
+    );
+    let v: Value = serde_json::from_str(stdout.trim())
+        .unwrap_or_else(|e| panic!("fetch not JSON: {stdout:?}: {e}"));
+    assert_eq!(v["schema_version"], "fetch_result.v1");
+    assert_eq!(v["kind"], "chunk");
+    assert!(
+        v["chunk"].is_object(),
+        "target chunk must be populated: {v}"
+    );
+    assert_eq!(v["truncated"], false);
+}
+
+#[test]
+fn fetch_doc_json_with_max_tokens_truncates() {
+    let dir = tempfile::tempdir().unwrap();
+    let (cfg, workspace, _data) = common::write_config(dir.path(), 30);
+    let body: String = "Lorem ipsum dolor sit amet. ".repeat(20);
+    fs::write(workspace.join("big.md"), format!("# Big\n\n{body}\n")).unwrap();
+    common::ingest(&cfg, &workspace);
+
+    // Find doc_id via search.
+    let (search_stdout, _) = common::run_search_with_args(
+        &cfg,
+        &["--json", "--mode", "lexical", "--k", "1", "Lorem"],
+    );
+    let search: Value = serde_json::from_str(search_stdout.trim())
+        .unwrap_or_else(|e| panic!("search not JSON: {search_stdout:?}: {e}"));
+    let doc_id = search["hits"][0]["doc_id"]
+        .as_str()
+        .expect("doc_id on first hit")
+        .to_string();
+
+    let (stdout, _) = common::run_fetch_with_args(
+        &cfg,
+        &["--json", "doc", &doc_id, "--max-tokens", "20"],
+    );
+    let v: Value = serde_json::from_str(stdout.trim())
+        .unwrap_or_else(|e| panic!("fetch not JSON: {stdout:?}: {e}"));
+    assert_eq!(v["kind"], "doc");
+    assert_eq!(
+        v["truncated"], true,
+        "20-token cap must trip truncation: {v}"
+    );
+}
+
+#[test]
+fn fetch_chunk_unknown_id_exits_with_error_v1() {
+    let dir = tempfile::tempdir().unwrap();
+    let (cfg, _workspace, _data) = common::write_config(dir.path(), 30);
+
+    // Direct invocation (not via the success-asserting helper) so we
+    // can read stderr on failure — mirrors the stale_cursor test in
+    // `wire_search_response.rs`.
+    let exe = env!("CARGO_BIN_EXE_kebab");
+    let cfg_str = cfg.to_str().expect("utf8");
+    let out = std::process::Command::new(exe)
+        .args([
+            "--config",
+            cfg_str,
+            "--json",
+            "fetch",
+            "chunk",
+            "nonexistent",
+        ])
+        .output()
+        .expect("kebab fetch");
+
+    assert_ne!(out.status.code(), Some(0), "must exit non-zero");
+    let stderr = String::from_utf8_lossy(&out.stderr);
+    let err_line = stderr
+        .lines()
+        .find(|l| {
+            serde_json::from_str::<Value>(l)
+                .ok()
+                .and_then(|v| {
+                    v.get("schema_version")
+                        .and_then(|s| s.as_str())
+                        .map(String::from)
+                })
+                .as_deref()
+                == Some("error.v1")
+        })
+        .unwrap_or_else(|| panic!("no error.v1 line on stderr: {stderr:?}"));
+
+    let v: Value = serde_json::from_str(err_line).expect("error.v1 json");
+    assert_eq!(
+        v["code"], "chunk_not_found",
+        "code must be chunk_not_found: {err_line}"
+    );
+}