Add explicit read-only mixed source8 CLI checking

crates/oa-cli/src/lib.rs

@@ -170,6 +170,47 @@ fn disk_error(report: &mut Report, error: SourceFileError) {
     report.fail(3, code, error.to_string());
 }
 
+/// Validate captured mixed source8 bytes without creating an editable candidate.
+pub fn check_mixed(entry: &Path) -> Report {
+    let mut report = Report::empty(entry, "check-mixed");
+    let snapshot = match source_files::load_mixed_source(entry, LIMITS) {
+        Ok(snapshot) => snapshot,
+        Err(error) => {
+            disk_error(&mut report, error);
+            return report;
+        }
+    };
+    let diagnostics = if snapshot.diagnostics().is_empty() {
+        match language::check_mixed_bundle(snapshot.bundle(), LIMITS) {
+            Ok(checked) => checked.warnings().to_vec(),
+            Err(errors) => errors,
+        }
+    } else {
+        snapshot.diagnostics().to_vec()
+    };
+    if diagnostics
+        .iter()
+        .any(|d| d.diagnostic.severity == Severity::Error)
+    {
+        report.status = "invalid".into();
+        report.exit_code = if diagnostics.iter().any(|d| {
+            matches!(
+                d.diagnostic.code.as_str(),
+                "pending_save" | "missing_include" | "invalid_path"
+            )
+        }) {
+            3
+        } else {
+            1
+        };
+    }
+    report.diagnostics = diagnostics
+        .into_iter()
+        .map(|d| located(d, "input"))
+        .collect();
+    report
+}
+
 /// A candidate owns its original expectations and is consumed by saving.
 /// Callers cannot replace its source/model/expectations after preparation.
 pub struct Prepared {
@@ -406,14 +447,19 @@ fn unified_diff(path: &str, before: &str, after: &str) -> String {
     out
 }
 
+/// Read-only mixed checking cannot acquire ordinary edit/write authority.
+pub enum Dispatch {
+    Editable { operation: Operation, write: bool },
+    CheckMixed,
+}
+
 pub struct Arguments {
     pub entry: PathBuf,
-    pub operation: Operation,
-    pub write: bool,
+    pub dispatch: Dispatch,
     pub json: bool,
 }
 
-pub const HELP: &str = "arcadia check ROOT [--json]\narcadia lint ROOT [--json]\narcadia stabilize ROOT [--write] [--json]\narcadia rename-alias ROOT OLD NEW [--write] [--json]\n\nROOT is an explicit .arcadia entry file; includes resolve relative to it.\nMutation commands preview by default. --write applies this invocation's candidate.\nMissing UUIDs in a preview are provisional until written. No canonical formatting.\nExit: 0 valid/success (engineering warnings allowed), 1 invalid source or semantic\ncommand rejection, 2 usage, 3 disk/path/conflict/pending-journal/output failure.\nNo implicit journal recovery. Limits: 64 MiB, 256 files, include depth32/edges1024,\n100000 graph objects, 250000 records, 500000 ordered references.\n";
+pub const HELP: &str = "arcadia check ROOT [--json]\narcadia lint ROOT [--json]\narcadia check-mixed ROOT [--json]\narcadia stabilize ROOT [--write] [--json]\narcadia rename-alias ROOT OLD NEW [--write] [--json]\n\nROOT is an explicit .arcadia entry file; includes resolve relative to it.\ncheck-mixed requires source8 and explicit UUIDs; it never migrates, stabilizes or writes.\nMutation commands preview by default. --write applies this invocation's candidate.\nMissing UUIDs in a preview are provisional until written. No canonical formatting.\nExit: 0 valid/success (engineering warnings allowed), 1 invalid source or semantic\ncommand rejection, 2 usage, 3 disk/path/conflict/pending-journal/output failure.\nNo implicit journal recovery. Limits: 64 MiB, 256 files, include depth32/edges1024,\n100000 graph objects, 250000 records, 500000 ordered references.\n";
 
 pub fn arguments(args: &[std::ffi::OsString]) -> Result<Arguments, String> {
     let mut positional = Vec::new();
@@ -433,19 +479,28 @@ pub fn arguments(args: &[std::ffi::OsString]) -> Result<Arguments, String> {
         }
     }
     let command = positional.first().and_then(|s| s.to_str()).unwrap_or("");
-    let operation = match (command, positional.len()) {
-        ("check" | "lint", 2) if !write => Operation::Check,
-        ("stabilize", 2) => Operation::Stabilize,
-        ("rename-alias", 4) => Operation::RenameAlias {
-            old: positional[2].to_str().ok_or("Alias must be UTF-8")?.into(),
-            new: positional[3].to_str().ok_or("Alias must be UTF-8")?.into(),
+    let dispatch = match (command, positional.len()) {
+        ("check-mixed", 2) if !write => Dispatch::CheckMixed,
+        ("check" | "lint", 2) if !write => Dispatch::Editable {
+            operation: Operation::Check,
+            write,
+        },
+        ("stabilize", 2) => Dispatch::Editable {
+            operation: Operation::Stabilize,
+            write,
+        },
+        ("rename-alias", 4) => Dispatch::Editable {
+            operation: Operation::RenameAlias {
+                old: positional[2].to_str().ok_or("Alias must be UTF-8")?.into(),
+                new: positional[3].to_str().ok_or("Alias must be UTF-8")?.into(),
+            },
+            write,
         },
         _ => return Err(HELP.into()),
     };
     Ok(Arguments {
         entry: PathBuf::from(positional[1]),
-        operation,
-        write,
+        dispatch,
         json,
     })
 }

crates/oa-cli/src/main.rs

@@ -1,4 +1,4 @@
-use oa_cli::{Report, arguments, prepare};
+use oa_cli::{Dispatch, Report, arguments, check_mixed, prepare};
 use std::{
     io::{self, Write},
     path::Path,
@@ -26,13 +26,21 @@ fn human_report(report: &Report, show_diff: bool) -> io::Result<()> {
             d.severity, d.code, d.coordinate_space, d.message
         )?;
     }
-    writeln!(
-        err,
-        "{}: {} file changes; {} identities to stabilize",
-        report.status,
-        report.changes.len(),
-        report.identities_to_stabilize
-    )?;
+    if report.operation == "check-mixed" {
+        writeln!(
+            err,
+            "{}: mixed source8 check; no files changed",
+            report.status
+        )?;
+    } else {
+        writeln!(
+            err,
+            "{}: {} file changes; {} identities to stabilize",
+            report.status,
+            report.changes.len(),
+            report.identities_to_stabilize
+        )?;
+    }
     if let Some(migration) = &report.migration {
         writeln!(
             err,
@@ -67,19 +75,22 @@ fn run() -> io::Result<u8> {
     let mut displayed = false;
     let report = match arguments(&args) {
         Err(error) => Report::failure(Path::new(""), "usage", 2, "usage", error),
-        Ok(args) => match prepare(&args.entry, args.operation) {
-            Err(report) => *report,
-            Ok(prepared) => {
-                if args.write {
-                    if !args.json {
-                        human_report(prepared.report(), true)?;
-                        displayed = true;
+        Ok(args) => match args.dispatch {
+            Dispatch::CheckMixed => check_mixed(&args.entry),
+            Dispatch::Editable { operation, write } => match prepare(&args.entry, operation) {
+                Err(report) => *report,
+                Ok(prepared) => {
+                    if write {
+                        if !args.json {
+                            human_report(prepared.report(), true)?;
+                            displayed = true;
+                        }
+                        prepared.write()
+                    } else {
+                        prepared.into_report()
                     }
-                    prepared.write()
-                } else {
-                    prepared.into_report()
                 }
-            }
+            },
         },
     };
     if json {

crates/oa-cli/tests/mixed_cli.rs

@@ -0,0 +1,490 @@
+//! Actual executable tests. Expected values are authored independently of CLI output.
+use oa_core::language::Span;
+use oa_core::source_project::{SourceBundle, SourceDiagnostic};
+pub use oa_core::*;
+use serde_json::{Value, json};
+use std::{
+    collections::BTreeMap,
+    fs,
+    path::{Path, PathBuf},
+    process::{Command, Output},
+};
+#[path = "../../oa-core/src/language/analysis_source/model_oracle.rs"]
+mod independent_model;
+
+fn id(n: u128) -> Id {
+    Id::from_u128(n)
+}
+fn document(body: &str) -> String {
+    format!(
+        "arcadia 8;\nproject p \"Project\" id \"{}\" {{\n{body}\n}}\n",
+        id(1)
+    )
+}
+fn authored_span(source: &str, literal: &str) -> Span {
+    assert_eq!(source.matches(literal).count(), 1);
+    let start = source.find(literal).unwrap();
+    Span {
+        start,
+        end: start + literal.len(),
+    }
+}
+struct Fixture(PathBuf);
+impl Fixture {
+    fn new() -> Self {
+        let p = std::env::temp_dir().join(format!("arcadia-mixed-cli-{}", Id::new_v4()));
+        fs::create_dir(&p).unwrap();
+        Self(p)
+    }
+    fn put(&self, name: &str, bytes: impl AsRef<[u8]>) {
+        let p = self.0.join(name);
+        fs::create_dir_all(p.parent().unwrap()).unwrap();
+        fs::write(p, bytes).unwrap();
+    }
+    fn entry(&self) -> PathBuf {
+        self.0.join("main.arcadia")
+    }
+    fn inventory(&self) -> BTreeMap<PathBuf, Option<Vec<u8>>> {
+        fn walk(root: &Path, dir: &Path, out: &mut BTreeMap<PathBuf, Option<Vec<u8>>>) {
+            for item in fs::read_dir(dir).unwrap() {
+                let p = item.unwrap().path();
+                if p.is_dir() {
+                    out.insert(p.strip_prefix(root).unwrap().into(), None);
+                    walk(root, &p, out);
+                } else {
+                    out.insert(
+                        p.strip_prefix(root).unwrap().into(),
+                        Some(fs::read(p).unwrap()),
+                    );
+                }
+            }
+        }
+        let mut out = BTreeMap::new();
+        walk(&self.0, &self.0, &mut out);
+        out
+    }
+    fn run(&self, options: &[&str]) -> Output {
+        let before = self.inventory();
+        let result = Command::new(env!("CARGO_BIN_EXE_arcadia"))
+            .arg("check-mixed")
+            .arg(self.entry())
+            .args(options)
+            .output()
+            .unwrap();
+        assert_eq!(
+            self.inventory(),
+            before,
+            "all file bytes and directory entries preserved"
+        );
+        result
+    }
+    fn expect(&self, exit: i32, diagnostics: Vec<Value>) {
+        let output = self.run(&["--json"]);
+        assert_eq!(
+            output.status.code(),
+            Some(exit),
+            "{}",
+            String::from_utf8_lossy(&output.stdout)
+        );
+        assert!(
+            output.stderr.is_empty(),
+            "{}",
+            String::from_utf8_lossy(&output.stderr)
+        );
+        assert_eq!(
+            serde_json::from_slice::<Value>(&output.stdout).unwrap(),
+            self.report(exit, diagnostics)
+        );
+    }
+    fn report(&self, exit: i32, diagnostics: Vec<Value>) -> Value {
+        json!({"format_version":1,"entry":self.entry().to_string_lossy(),"operation":"check-mixed",
+            "status":if exit==0 {"checked"}else{"invalid"},"exit_code":exit,"written":false,
+            "diagnostics":diagnostics,"changes":[],"identities_to_stabilize":0,"migration":null,"notes":[]})
+    }
+}
+impl Drop for Fixture {
+    fn drop(&mut self) {
+        fs::remove_dir_all(&self.0).unwrap();
+    }
+}
+fn diagnostic(source: &str, path: &str, span: Span, code: &str, message: &str) -> Value {
+    let prefix = &source[..span.start];
+    json!({"severity":"error","code":code,"message":message,"coordinate_space":"input",
+        "location":{"path":path,"start":span.start,"end":span.end,
+            "line":prefix.bytes().filter(|b|*b==b'\n').count()+1,
+            "column":prefix.rsplit('\n').next().unwrap().chars().count()+1},
+        "related":[],"object_id":null,"field":null})
+}
+fn warning(d: &SourceDiagnostic) -> Value {
+    let at = &d.diagnostic;
+    assert!(d.related.is_empty());
+    json!({"severity":"warning","code":at.code,"message":at.message,"coordinate_space":"input",
+        "location":{"path":d.path,"start":at.span.start,"end":at.span.end,"line":at.line,"column":at.column},
+        "related":[],"object_id":at.object_id.unwrap().to_string(),"field":at.field})
+}
+fn rich(layer: Layer, crlf: bool) -> (SourceBundle, Project, Vec<SourceDiagnostic>) {
+    let (ordinary, typed, work) = match layer {
+        Layer::Oa => (
+            include_str!(
+                "../../oa-core/src/language/analysis_source/lower/fixtures/ordinary-oa.arcadia"
+            ),
+            include_str!(
+                "../../oa-core/src/language/analysis_source/lower/fixtures/typed-oa.arcadia"
+            ),
+            "oa_activity",
+        ),
+        Layer::Sa => (
+            include_str!(
+                "../../oa-core/src/language/analysis_source/lower/fixtures/ordinary-sa.arcadia"
+            ),
+            include_str!(
+                "../../oa-core/src/language/analysis_source/lower/fixtures/typed-sa.arcadia"
+            ),
+            "sa_function",
+        ),
+    };
+    let mut expected = independent_model::project(layer);
+    let mut main = ordinary
+        .replace("\r\n", "\n")
+        .replacen("arcadia 7;", "arcadia 8;", 1);
+    assert!(main.starts_with("arcadia 8;"));
+    // Forward typed uses refer back into nested ordinary Work in this file.
+    main = main.replacen("{\n", "{\n    include \"typed.arcadia\";\n", 1);
+    if layer == Layer::Sa {
+        let system = Element {
+            id: id(999),
+            alias: "system".into(),
+            name: "System".into(),
+            description: String::new(),
+            parent: None,
+            body: ElementBody::Sa(SaBody::System),
+        };
+        let at = main.rfind('}').unwrap();
+        main.insert_str(
+            at,
+            &format!(
+                "    sa_system system \"System\" id \"{}\" {{}}\n",
+                system.id
+            ),
+        );
+        assert!(expected.elements.insert(system.id, system).is_none());
+    }
+    let mut typed = typed.replace("\r\n", "\n");
+    // Textual argument order is independent of the model's parameter-ID map.
+    assert!(typed.contains("@combine(a: @receive_time, b: @dispatch_time)"));
+    typed = typed.replace(
+        "@combine(a: @receive_time, b: @dispatch_time)",
+        "@combine(b: @dispatch_time, a: @receive_time)",
+    );
+    if crlf {
+        main = format!("// 港🌊\r\n{}", main.replace('\n', "\r\n"));
+        typed = typed.replace('\n', "\r\n");
+    }
+    let bundle = SourceBundle {
+        entry: "main.arcadia".into(),
+        files: BTreeMap::from([
+            ("main.arcadia".into(), main),
+            ("typed.arcadia".into(), typed),
+        ]),
+    };
+    // Two nested leaves, so four warnings, unlike the earlier one-Work fixture.
+    // Existing validation orders both allocation warnings before coverage warnings.
+    let mut warnings = Vec::new();
+    for allocation in [true, false] {
+        for (alias, display) in [("receive", "Receive"), ("dispatch", "Dispatch")] {
+            let element = expected
+                .elements
+                .values()
+                .find(|e| e.alias == alias)
+                .unwrap();
+            let literal = format!("{work} {alias} \"{display}\" id \"{}\" {{}}", element.id);
+            let source = &bundle.files["main.arcadia"];
+            let span = authored_span(source, &literal);
+            let prefix = &source[..span.start];
+            warnings.push(SourceDiagnostic {
+                path: "main.arcadia".into(), related: Vec::new(),
+                diagnostic: language::Diagnostic {
+                    severity: validation::Severity::Warning,
+                    code: if allocation { "unallocated_leaf" } else { "work_without_behavior_context" }.into(),
+                    object_id: Some(element.id),
+                    field: allocation.then(|| "allocation".into()),
+                    message: if allocation { format!("Allocate leaf '{display}' to a performer.") } else {
+                        "Include this leaf activity/function in a process/chain or scenario through a work action or exchange occurrence.".into()
+                    },
+                    span, line: prefix.bytes().filter(|b| *b == b'\n').count() + 1,
+                    column: prefix.rsplit('\n').next().unwrap().chars().count() + 1,
+                },
+            });
+        }
+    }
+    (bundle, expected, warnings)
+}
+
+#[test]
+fn mixed_cli_complete_oa_sa_models_reports_and_unchanged_bytes() {
+    for layer in [Layer::Oa, Layer::Sa] {
+        for crlf in [false, true] {
+            let (mut bundle, expected, _) = rich(layer, crlf);
+            // Escaped include path and a decoy in a comment exercise real grammar discovery.
+            let main = bundle.files.get_mut("main.arcadia").unwrap();
+            *main = main.replace("typed.arcadia", "typed\\u002earcadia");
+            let comment = if crlf {
+                "// include \"missing.arcadia\"; 港🌊\r\n"
+            } else {
+                "// include \"missing.arcadia\"; 港🌊\n"
+            };
+            main.insert_str(0, comment);
+            // Rebuild only warning locations from unique authored declaration literals,
+            // never from parsed diagnostics or emitted reports.
+            let (_, _, mut warnings) = rich(layer, crlf);
+            for d in &mut warnings {
+                let e = &expected.elements[&d.diagnostic.object_id.unwrap()];
+                let work = if layer == Layer::Oa {
+                    "oa_activity"
+                } else {
+                    "sa_function"
+                };
+                let literal = format!("{work} {} \"{}\" id \"{}\" {{}}", e.alias, e.name, e.id);
+                let span = authored_span(main, &literal);
+                let prefix = &main[..span.start];
+                d.diagnostic.span = span;
+                d.diagnostic.line = prefix.bytes().filter(|b| *b == b'\n').count() + 1;
+                d.diagnostic.column = prefix.rsplit('\n').next().unwrap().chars().count() + 1;
+            }
+            let f = Fixture::new();
+            for (path, text) in &bundle.files {
+                f.put(path, text);
+            }
+            f.put("unrelated/keep.bin", [0, 255, 13, 10]);
+            let snapshot = source_files::load_mixed_source(&f.entry(), oa_cli::LIMITS).unwrap();
+            assert!(snapshot.diagnostics().is_empty());
+            assert_eq!(snapshot.bundle(), &bundle);
+            let checked = language::check_mixed_bundle(snapshot.bundle(), oa_cli::LIMITS)
+                .unwrap_or_else(|e| panic!("{e:#?}"));
+            assert_eq!(checked.project(), &expected);
+            assert_eq!(checked.warnings(), warnings);
+            f.expect(0, warnings.iter().map(warning).collect());
+        }
+    }
+}
+
+#[test]
+fn mixed_cli_missing_id_classes_and_schema_are_exact_refusals() {
+    let ordinary = format!("oa_entity e \"Entity\" id \"{}\" {{}}", id(2));
+    let typed = format!(
+        "calculation f \"Calculation\" id \"{}\" {{ input x id \"{}\" : Number; result Number; body $x; }}",
+        id(3),
+        id(1)
+    );
+    let valid = document(&format!("{ordinary}\n{typed}"));
+    let f = Fixture::new();
+    f.put("main.arcadia", &valid);
+    f.expect(0, vec![]);
+    for (needle, replacement, anchor) in [
+        (format!("id \"{}\"", id(1)), String::new(), "project"),
+        (format!("id \"{}\"", id(2)), String::new(), "oa_entity"),
+        (format!("id \"{}\"", id(3)), String::new(), "calculation"),
+        (
+            format!("input x id \"{}\"", id(1)),
+            "input x".into(),
+            "calculation",
+        ),
+    ] {
+        let source = valid.replacen(&needle, &replacement, 1);
+        let begin = source.find(anchor).unwrap();
+        let start = if anchor == "calculation" {
+            begin
+        } else {
+            begin + source[begin..].find('{').unwrap()
+        };
+        f.put("main.arcadia", &source);
+        f.expect(
+            1,
+            vec![diagnostic(
+                &source,
+                "main.arcadia",
+                Span {
+                    start,
+                    end: start + 1,
+                },
+                "invalid_source",
+                "Mixed source8 requires explicit UUIDs.",
+            )],
+        );
+    }
+    for schema in [3, 7, 9] {
+        let source = document("").replacen("arcadia 8", &format!("arcadia {schema}"), 1);
+        f.put("main.arcadia", &source);
+        f.expect(
+            1,
+            vec![diagnostic(
+                &source,
+                "main.arcadia",
+                Span { start: 8, end: 9 },
+                "invalid_source",
+                "Mixed source requires arcadia 8.",
+            )],
+        );
+    }
+}
+
+#[test]
+fn mixed_cli_final_semantic_refusal_keeps_original_cross_file_coordinates() {
+    let f = Fixture::new();
+    f.put("main.arcadia", document("include \"part.arcadia\";"));
+    let part = format!(
+        "// 港🌊\r\ncalculation f \"Calculation\" id \"{}\" {{ input x id \"{}\" : Number; result Number; body @missing(x: $x); }}\r\n",
+        id(2),
+        id(1)
+    );
+    let start = part.find("@missing").unwrap() + 1;
+    f.put("part.arcadia", &part);
+    f.expect(
+        1,
+        vec![diagnostic(
+            &part,
+            "part.arcadia",
+            Span {
+                start,
+                end: start + 7,
+            },
+            "invalid_source",
+            "Unknown global reference '@missing'.",
+        )],
+    );
+}
+
+#[test]
+fn mixed_cli_disk_discovery_and_cycle_refusals_preserve_every_entry() {
+    let f = Fixture::new();
+    let source = document("include \"part.arcadia\";");
+    let span = authored_span(&source, "include \"part.arcadia\";");
+    f.put("main.arcadia", &source);
+    let missing = f.0.canonicalize().unwrap().join("part.arcadia");
+    let os_error = fs::symlink_metadata(&missing).unwrap_err();
+    f.expect(
+        3,
+        vec![diagnostic(
+            &source,
+            "main.arcadia",
+            span,
+            "missing_include",
+            &format!(
+                "Cannot load 'part.arcadia': Source file operation failed at {}: {os_error}",
+                missing.display()
+            ),
+        )],
+    );
+    f.put("part.arcadia", [0xff]);
+    f.expect(
+        1,
+        vec![diagnostic(
+            &source,
+            "main.arcadia",
+            span,
+            "source_encoding",
+            "'part.arcadia' is not UTF-8 source.",
+        )],
+    );
+    let part = "include \"main.arcadia\";";
+    f.put("part.arcadia", part);
+    f.expect(
+        1,
+        vec![diagnostic(
+            part,
+            "part.arcadia",
+            Span { start: 0, end: 23 },
+            "include_cycle",
+            "Include cycle: main.arcadia -> part.arcadia -> main.arcadia.",
+        )],
+    );
+    let escape = document("include \"../escape.arcadia\";");
+    f.put("main.arcadia", &escape);
+    f.expect(
+        3,
+        vec![diagnostic(
+            &escape,
+            "main.arcadia",
+            authored_span(&escape, "include \"../escape.arcadia\";"),
+            "invalid_path",
+            "Include escapes the source project root.",
+        )],
+    );
+    f.put("main.arcadia", document(""));
+    let journal = f.0.join(".arcadia-save-main.arcadia.journal");
+    fs::create_dir(&journal).unwrap();
+    fs::write(journal.join("sentinel"), b"keep").unwrap();
+    let physical =
+        f.0.canonicalize()
+            .unwrap()
+            .join(".arcadia-save-main.arcadia.journal");
+    f.expect(
+        3,
+        vec![diagnostic(
+            &document(""),
+            "main.arcadia",
+            Span { start: 0, end: 0 },
+            "pending_save",
+            &format!(
+                "A save was interrupted. Review and recover {} before saving this project.",
+                physical.display()
+            ),
+        )],
+    );
+}
+
+#[test]
+fn mixed_cli_usage_and_human_output_never_suggest_an_edit_candidate() {
+    let f = Fixture::new();
+    f.put("main.arcadia", document(""));
+    let output = f.run(&[]);
+    assert!(output.status.success());
+    assert!(output.stdout.is_empty());
+    assert_eq!(
+        output.stderr,
+        b"checked: mixed source8 check; no files changed\n"
+    );
+    for options in [
+        vec!["--write", "--json"],
+        vec!["--unknown", "--json"],
+        vec!["--json", "--json"],
+    ] {
+        let output = f.run(&options);
+        assert_eq!(output.status.code(), Some(2));
+        assert!(output.stderr.is_empty());
+        let message = if options[0] == "--write" {
+            oa_cli::HELP.to_string()
+        } else if options[0] == "--unknown" {
+            "Unknown or repeated option: --unknown".into()
+        } else {
+            "Unknown or repeated option: --json".into()
+        };
+        assert_eq!(
+            serde_json::from_slice::<Value>(&output.stdout).unwrap(),
+            json!({"format_version":1,"entry":"","operation":"usage","status":"rejected","exit_code":2,"written":false,
+            "diagnostics":[{"severity":"error","code":"usage","message":message,"coordinate_space":"operation","location":null,"related":[],"object_id":null,"field":null}],"changes":[],"identities_to_stabilize":0,"migration":null,"notes":[]})
+        );
+    }
+}
+
+#[test]
+fn mixed_cli_direct_disk_error_uses_existing_operation_error_envelope() {
+    let f = Fixture::new();
+    f.put(".arcadia-save-reserved.arcadia", document(""));
+    let before = f.inventory();
+    let entry = f.0.join(".arcadia-save-reserved.arcadia");
+    let output = Command::new(env!("CARGO_BIN_EXE_arcadia"))
+        .arg("check-mixed")
+        .arg(&entry)
+        .arg("--json")
+        .output()
+        .unwrap();
+    assert_eq!(f.inventory(), before);
+    assert_eq!(output.status.code(), Some(3));
+    assert!(output.stderr.is_empty());
+    assert_eq!(
+        serde_json::from_slice::<Value>(&output.stdout).unwrap(),
+        json!({"format_version":1,"entry":entry.to_string_lossy(),"operation":"check-mixed","status":"rejected","exit_code":3,"written":false,
+        "diagnostics":[{"severity":"error","code":"unsafe_path","message":"Unsafe source path: Non-canonical, reserved or overlong path '.arcadia-save-reserved.arcadia'.","coordinate_space":"operation","location":null,"related":[],"object_id":null,"field":null}],"changes":[],"identities_to_stabilize":0,"migration":null,"notes":[]})
+    );
+}