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harn_cli/commands/
precompile.rs

1//! `harn precompile` — dispatches the directory-walk + per-file fanout
2//! to the embedded `cli/precompile.harn` script.
3//!
4//! The .harn port owns argv parsing, walking, --out path mirroring, and
5//! the per-file progress and summary render. The actual parse, typecheck,
6//! and compile work stays in Rust behind a command-specific internal mode:
7//! the script spawns `harn precompile <single-file>` per source with
8//! `HARN_PRECOMPILE_INNER=1` so the child compiles one source instead of
9//! recursing back into the directory walker.
10//!
11//! Phase deferrals: `harn time` and `harn bench` (the other two W13
12//! commands) stay Rust-only in this PR — both depend on in-process VM
13//! thread-locals (LLM trace summary, profile spans, `getrusage` CPU
14//! samples) that don't survive a `spawn_captured` subprocess boundary
15//! without inventing a new child-binary emit protocol. The W13 ticket
16//! description presumed an `--internal-phase-emit` protocol on `harn
17//! run` that doesn't actually exist in the current codebase; the
18//! preconditions for porting each are filed as #2348 (`harn bench` →
19//! `--emit-summary-json`) and #2350 (`harn time` → `--emit-phase-json`).
20//!
21use std::path::{Path, PathBuf};
22
23use harn_parser::DiagnosticSeverity;
24use harn_vm::module_artifact::ModuleArtifact;
25
26use crate::cli::PrecompileArgs;
27use crate::command_error;
28use crate::commands::collect_harn_files;
29use crate::dispatch;
30use crate::env_guard::ScopedEnvVar;
31use crate::parse_source_file;
32use crate::typecheck_imports::checker_with_resolved_imports;
33
34/// Env var the embedded `cli/precompile` script reads to find the
35/// running `harn` binary path. Set from `std::env::current_exe()` so
36/// the child invocation is robust to $PATH ordering / test sandboxes.
37pub const PRECOMPILE_BIN_ENV: &str = "HARN_CLI_SELF_EXE";
38
39/// Output directory the script forwards to its per-file child via
40/// `--out`. Cleared on drop so a follow-on invocation in the same
41/// process sees a clean env.
42const PRECOMPILE_OUT_ENV: &str = "HARN_PRECOMPILE_OUT";
43const PRECOMPILE_KEEP_GOING_ENV: &str = "HARN_PRECOMPILE_KEEP_GOING";
44const PRECOMPILE_QUIET_ENV: &str = "HARN_PRECOMPILE_QUIET";
45pub const PRECOMPILE_INNER_ENV: &str = "HARN_PRECOMPILE_INNER";
46
47pub async fn run(args: PrecompileArgs) {
48    if std::env::var(PRECOMPILE_INNER_ENV).as_deref() == Ok("1") {
49        run_inner_compile(args);
50        return;
51    }
52
53    let exe = std::env::current_exe().unwrap_or_else(|error| {
54        command_error(&format!("failed to resolve current executable: {error}"))
55    });
56    let exe_str = exe.to_string_lossy().into_owned();
57    let _bin = ScopedEnvVar::set(PRECOMPILE_BIN_ENV, &exe_str);
58    let _out = args
59        .out
60        .as_ref()
61        .map(|p| ScopedEnvVar::set(PRECOMPILE_OUT_ENV, &p.to_string_lossy()));
62    let _keep = if args.keep_going {
63        Some(ScopedEnvVar::set(PRECOMPILE_KEEP_GOING_ENV, "1"))
64    } else {
65        None
66    };
67    let _quiet = if args.quiet {
68        Some(ScopedEnvVar::set(PRECOMPILE_QUIET_ENV, "1"))
69    } else {
70        None
71    };
72
73    let argv = vec![args.target.to_string_lossy().into_owned()];
74    // Use the no-sandbox dispatch: precompile's target is whatever path
75    // the user passed, which is typically outside the script's
76    // tempfile-derived workspace root. The actual compile work still
77    // runs inside the spawned child's default sandbox; the orchestration
78    // layer this script implements just needs to read directory entries.
79    let exit = dispatch::dispatch_to_embedded_script_no_sandbox(
80        "precompile",
81        argv,
82        /* json_mode */ false,
83    )
84    .await;
85    if exit != 0 {
86        std::process::exit(exit);
87    }
88}
89
90/// Outcome aggregated across all sources walked in one invocation.
91#[derive(Default)]
92struct Stats {
93    compiled: usize,
94    failed: usize,
95}
96
97/// One file can be both an executable entry pipeline AND an imported
98/// module. Precompile emits both so the runtime loader hits whichever
99/// path the user takes.
100struct PrecompileArtifacts {
101    entry_chunk: harn_vm::Chunk,
102    module_artifact: Option<ModuleArtifact>,
103}
104
105/// Rust compiler entrypoint used by the `.harn` directory-walk driver for
106/// each source file.
107pub fn run_inner_compile(args: PrecompileArgs) {
108    let target = args.target.clone();
109    if !target.exists() {
110        command_error(&format!("target does not exist: {}", target.display()));
111    }
112
113    let (sources, source_root) = if target.is_dir() {
114        let mut files = Vec::new();
115        collect_harn_files(&target, &mut files);
116        files.sort();
117        files.dedup();
118        let root = target.canonicalize().unwrap_or_else(|_| target.clone());
119        (files, Some(root))
120    } else {
121        (vec![target.clone()], None)
122    };
123
124    if sources.is_empty() {
125        command_error(&format!("no .harn files found under {}", target.display()));
126    }
127
128    let mut stats = Stats::default();
129    for source in &sources {
130        let result = precompile_one(source, source_root.as_deref(), args.out.as_deref());
131        match result {
132            Ok(out_path) => {
133                stats.compiled += 1;
134                if !args.quiet {
135                    println!("{} -> {}", source.display(), out_path.display());
136                }
137            }
138            Err(err) => {
139                stats.failed += 1;
140                eprintln!("{}: {err}", source.display());
141                if !args.keep_going {
142                    break;
143                }
144            }
145        }
146    }
147
148    if !args.quiet {
149        eprintln!(
150            "precompile: {} succeeded, {} failed",
151            stats.compiled, stats.failed
152        );
153    }
154    if stats.failed > 0 {
155        std::process::exit(1);
156    }
157}
158
159fn precompile_one(
160    source_path: &Path,
161    source_root: Option<&Path>,
162    out_root: Option<&Path>,
163) -> Result<PathBuf, String> {
164    let source = std::fs::read_to_string(source_path).map_err(|e| format!("read: {e}"))?;
165    let path_str = source_path.to_string_lossy();
166
167    let (parsed_source, program) = parse_source_file(&path_str);
168    debug_assert_eq!(parsed_source, source);
169
170    // Resolve imports like `execute`/`harn check` so a call to an imported
171    // symbol that shadows a builtin is checked against the right signature.
172    let checker = checker_with_resolved_imports(harn_parser::TypeChecker::new(), source_path);
173
174    let mut had_type_error = false;
175    let mut messages = String::new();
176    for diag in checker.check_with_source(&program, &source) {
177        let rendered = harn_parser::diagnostic::render_type_diagnostic(&source, &path_str, &diag);
178        if matches!(diag.severity, DiagnosticSeverity::Error) {
179            had_type_error = true;
180        }
181        messages.push_str(&rendered);
182    }
183    if had_type_error {
184        return Err(format!("type errors:\n{messages}"));
185    }
186    if !messages.is_empty() {
187        eprint!("{messages}");
188    }
189
190    let artifacts = compile_artifacts(source_path, &program)?;
191    let key = harn_vm::bytecode_cache::CacheKey::from_source(source_path, &source);
192
193    let entry_dest = output_path(
194        source_path,
195        source_root,
196        out_root,
197        harn_vm::bytecode_cache::CACHE_EXTENSION,
198    )?;
199    harn_vm::bytecode_cache::store_at(&entry_dest, &key, &artifacts.entry_chunk)
200        .map_err(|e| format!("write {}: {e}", entry_dest.display()))?;
201
202    if let Some(module_artifact) = &artifacts.module_artifact {
203        let module_dest = output_path(
204            source_path,
205            source_root,
206            out_root,
207            harn_vm::bytecode_cache::MODULE_CACHE_EXTENSION,
208        )?;
209        harn_vm::bytecode_cache::store_module_at(&module_dest, &key, module_artifact)
210            .map_err(|e| format!("write {}: {e}", module_dest.display()))?;
211    }
212
213    Ok(entry_dest)
214}
215
216/// Compile both the entry-chunk view and the module-artifact view of the
217/// same source. A `.harn` file with a `pipeline default { ... }` block is
218/// callable as both an entry and an importable module; one without is
219/// importable but produces an entry chunk that just returns `nil`. We
220/// emit both artifacts unconditionally so the runtime loader hits the
221/// cache regardless of how the user invokes the file.
222fn compile_artifacts(
223    source_path: &Path,
224    program: &[harn_parser::SNode],
225) -> Result<PrecompileArtifacts, String> {
226    let entry_chunk = harn_vm::Compiler::new()
227        .compile(program)
228        .map_err(|e| format!("compile error: {e}"))?;
229    let module_artifact = harn_vm::module_artifact::compile_module_artifact(
230        program,
231        Some(source_path.display().to_string()),
232    )
233    .map_err(|e| format!("module compile error: {e}"))
234    .ok();
235    Ok(PrecompileArtifacts {
236        entry_chunk,
237        module_artifact,
238    })
239}
240
241/// Map a source path under (optional) `source_root` to its destination
242/// under (optional) `out_root` with the given file extension. When no
243/// `out_root` is given the artifact lands adjacent to the source.
244fn output_path(
245    source_path: &Path,
246    source_root: Option<&Path>,
247    out_root: Option<&Path>,
248    extension: &str,
249) -> Result<PathBuf, String> {
250    let stem = source_path
251        .file_stem()
252        .ok_or_else(|| format!("source has no file stem: {}", source_path.display()))?;
253    let Some(out_root) = out_root else {
254        let parent = source_path.parent().unwrap_or_else(|| Path::new(""));
255        let mut adjacent = parent.join(stem);
256        adjacent.set_extension(extension);
257        return Ok(adjacent);
258    };
259    let relative = match source_root {
260        Some(root) => {
261            let canonical = source_path
262                .canonicalize()
263                .unwrap_or_else(|_| source_path.to_path_buf());
264            canonical
265                .strip_prefix(root)
266                .map(Path::to_path_buf)
267                .unwrap_or_else(|_| {
268                    PathBuf::from(source_path.file_name().unwrap_or(source_path.as_os_str()))
269                })
270        }
271        None => PathBuf::from(
272            source_path
273                .file_name()
274                .ok_or_else(|| format!("source has no file name: {}", source_path.display()))?,
275        ),
276    };
277    let mut dest = out_root.join(&relative);
278    dest.set_extension(extension);
279    Ok(dest)
280}