harn_parser/diagnostic_codes/
repairs.rs

1//! Repair vocabulary attached to a diagnostic code.
2//!
3//! A diagnostic says what is wrong; a repair says what an agent or editor may
4//! do about it and how far that action is allowed to reach. The safety ladder
5//! here is a contract surface — `harn fix --safety <class>` and IDE auto-apply
6//! ceilings both compare against it — so the wire strings are as stable as the
7//! codes themselves.
8//!
9//! Split out of `diagnostic_codes.rs` (#6126), which had reached its
10//! source-length ceiling and could not accept another code. The registry keeps
11//! the codes; this module keeps everything that answers "and what do I do".
12
13use std::{fmt, str::FromStr};
14
15use super::Code;
16
17/// Autonomy ceiling of a proposed repair.
18///
19/// Agents and IDEs use this class to auto-apply, suggest, or escalate a fix. Variants
20/// are ordered from least to most disruptive — call sites can compare
21/// with `<=` to enforce a configured ceiling like
22/// `"apply anything up to behavior-preserving"`.
23///
24/// The wire-format strings (`format-only`, `behavior-preserving`, …) are
25/// the contract surface; renaming a variant string is a breaking change.
26#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
27pub enum RepairSafety {
28    /// Whitespace, trivia, or canonical layout only. No code structure
29    /// changes; safe to auto-apply.
30    FormatOnly,
31    /// Intended not to change observable runtime behavior (e.g. delete an
32    /// unreachable branch, drop a redundant cast).
33    BehaviorPreserving,
34    /// Confined to the current local scope or file. Runtime behavior may
35    /// change, but the blast radius does not cross a declaration boundary
36    /// or a public surface.
37    ScopeLocal,
38    /// Touches a signature, export, or call-site surface that other files
39    /// or external consumers can observe.
40    SurfaceChanging,
41    /// Required capabilities or sandbox profile may change as a result of
42    /// applying the repair (e.g. swapping `provider: "openai"` for a
43    /// capability flag widens the routing surface).
44    CapabilityChanging,
45    /// Planning hint only — agents should propose, never auto-apply.
46    /// Aligned with the `AutonomyTier::Suggest`/`ActWithApproval` rungs
47    /// in `trust_graph.rs`.
48    NeedsHuman,
49}
50
51impl RepairSafety {
52    pub const ALL: &'static [RepairSafety] = &[
53        RepairSafety::FormatOnly,
54        RepairSafety::BehaviorPreserving,
55        RepairSafety::ScopeLocal,
56        RepairSafety::SurfaceChanging,
57        RepairSafety::CapabilityChanging,
58        RepairSafety::NeedsHuman,
59    ];
60
61    /// Stable wire-format string. The contract surface — do not rename
62    /// without coordinating with `harn fix --safety <…>` callers and
63    /// downstream LSP/IDE clients.
64    pub const fn as_str(self) -> &'static str {
65        match self {
66            RepairSafety::FormatOnly => "format-only",
67            RepairSafety::BehaviorPreserving => "behavior-preserving",
68            RepairSafety::ScopeLocal => "scope-local",
69            RepairSafety::SurfaceChanging => "surface-changing",
70            RepairSafety::CapabilityChanging => "capability-changing",
71            RepairSafety::NeedsHuman => "needs-human",
72        }
73    }
74
75    /// True when `self` sits at or below `ceiling`. Used by
76    /// `harn fix --apply --safety <ceiling>` and IDE auto-apply policies
77    /// to decide whether a repair clears the configured autonomy bar.
78    pub const fn is_at_most(self, ceiling: RepairSafety) -> bool {
79        (self as u8) <= (ceiling as u8)
80    }
81}
82
83impl fmt::Display for RepairSafety {
84    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
85        f.write_str(self.as_str())
86    }
87}
88
89/// Error returned when parsing an unknown repair-safety string.
90#[derive(Debug, Clone, Copy, PartialEq, Eq)]
91pub struct ParseRepairSafetyError;
92
93impl fmt::Display for ParseRepairSafetyError {
94    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
95        f.write_str("unknown Harn repair-safety class")
96    }
97}
98
99impl std::error::Error for ParseRepairSafetyError {}
100
101impl FromStr for RepairSafety {
102    type Err = ParseRepairSafetyError;
103
104    fn from_str(value: &str) -> Result<Self, Self::Err> {
105        RepairSafety::ALL
106            .iter()
107            .copied()
108            .find(|safety| safety.as_str() == value)
109            .ok_or(ParseRepairSafetyError)
110    }
111}
112
113/// Namespaced kebab-case repair identifier (e.g. `imports/fix-path`).
114///
115/// Wraps a `Cow` so registry-driven values reuse a `'static` literal and
116/// per-site overrides can still attach an owned string. The wire-format
117/// string is the contract surface — never normalize or reformat on read.
118#[derive(Debug, Clone, PartialEq, Eq, Hash)]
119pub struct RepairId(std::borrow::Cow<'static, str>);
120
121impl RepairId {
122    pub const fn from_static(s: &'static str) -> Self {
123        RepairId(std::borrow::Cow::Borrowed(s))
124    }
125
126    pub fn from_owned(s: String) -> Self {
127        RepairId(std::borrow::Cow::Owned(s))
128    }
129
130    pub fn as_str(&self) -> &str {
131        &self.0
132    }
133}
134
135impl fmt::Display for RepairId {
136    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
137        f.write_str(&self.0)
138    }
139}
140
141/// A structured repair proposal attached to a diagnostic.
142///
143/// `id` and `summary` are agent-readable metadata; `safety` is the
144/// dispatch dimension that decides whether the repair clears an
145/// autonomy ceiling. The concrete edits, when known statically, live on
146/// the diagnostic's `fix: Option<Vec<FixEdit>>`; this `Repair` is the
147/// classifier above those edits, not a replacement for them.
148#[derive(Debug, Clone)]
149pub struct Repair {
150    pub id: RepairId,
151    pub summary: String,
152    pub safety: RepairSafety,
153}
154
155impl Repair {
156    pub fn from_template(template: &RepairTemplate) -> Self {
157        Repair {
158            id: RepairId::from_static(template.id),
159            summary: template.summary.to_string(),
160            safety: template.safety,
161        }
162    }
163}
164
165/// Static-lifetime repair template bound to a diagnostic code.
166///
167/// Stored in the registry alongside `Code`. Construction sites can
168/// materialize a `Repair` via [`Repair::from_template`] or override
169/// `summary` for instance-specific detail by building a `Repair`
170/// directly.
171#[derive(Debug, Clone, Copy)]
172pub struct RepairTemplate {
173    pub id: &'static str,
174    pub summary: &'static str,
175    pub safety: RepairSafety,
176}
177
178impl Code {
179    /// Look up the default repair template attached to this diagnostic
180    /// code, or `None` if no actionable fix shape is registered.
181    pub const fn repair_template(self) -> Option<&'static RepairTemplate> {
182        match self {
183            // --- TYP: type mismatches & coercions -------------------------
184            Code::TypeMismatch
185            | Code::ReturnTypeMismatch
186            | Code::AssignmentTypeMismatch
187            | Code::ArgumentTypeMismatch
188            | Code::VariableTypeMismatch
189            | Code::ClosureReturnTypeMismatch
190            | Code::FieldTypeMismatch
191            | Code::MethodTypeMismatch
192            | Code::InvalidIndexType => Some(&REPAIR_INSERT_EXPLICIT_CONVERSION),
193            Code::StringInterpolationRewrite => Some(&REPAIR_REWRITE_STRING_INTERPOLATION),
194            Code::UnknownTypeName => Some(&REPAIR_IMPORTS_FIX_PATH),
195            Code::ImplicitAnyParameter => Some(&REPAIR_TYPES_ANNOTATE_PARAMETER),
196            Code::InvalidCast => Some(&REPAIR_CASTS_REMOVE_UNCHECKED),
197
198            // --- NAM / IMP: imports & names -------------------------------
199            Code::UndefinedVariable
200            | Code::UndefinedFunction
201            | Code::UnknownField
202            | Code::UnknownMethod
203            | Code::UnknownBuiltin
204            | Code::UnknownDeclaration => Some(&REPAIR_BINDINGS_RENAME_TO_CLOSEST),
205            Code::InvalidMainSignature => Some(&REPAIR_BINDINGS_THREAD_HARNESS_NEEDS_PARAM),
206            Code::DeprecatedFunction => Some(&REPAIR_STDLIB_MIGRATE_RENAMED),
207            Code::ModuleImportUnresolved | Code::ImportResolutionFailed => {
208                Some(&REPAIR_IMPORTS_FIX_PATH)
209            }
210            Code::ModuleImportUnused => Some(&REPAIR_IMPORTS_REMOVE_UNUSED),
211            Code::ModuleImportOrder => Some(&REPAIR_IMPORTS_REORDER),
212
213            // --- CAP / RCV: capabilities & error recovery -----------------
214            Code::CapabilityResultUnchecked => Some(&REPAIR_ERRORS_CHECK_OR_RESCUE),
215            Code::CapabilityBindingInvalid => Some(&REPAIR_MANUAL_REVIEW_CAPABILITY),
216            Code::EffectInheritanceViolation => Some(&REPAIR_POLICY_NARROW_CHILD_EFFECTS),
217            Code::RescueOutsideFunction | Code::TryOutsideFunction => {
218                Some(&REPAIR_ERRORS_WRAP_IN_FN)
219            }
220
221            // --- LLM / PRM: model + prompt contract -----------------------
222            Code::DeprecatedLlmOption => Some(&REPAIR_LLM_MIGRATE_DEPRECATED_OPTION),
223            Code::LlmSchemaMissing => Some(&REPAIR_LLM_ADD_SCHEMA),
224            Code::LlmProviderIdentityBranch | Code::PromptProviderIdentityBranch => {
225                Some(&REPAIR_LLM_USE_CAPABILITY_FLAG)
226            }
227            Code::PromptInjectionRisk => Some(&REPAIR_PROMPTS_ESCAPE_INJECTION),
228            Code::PromptToolSurfaceUnknown | Code::PromptToolSurfaceDeferredReference => {
229                Some(&REPAIR_PROMPTS_ADD_TOOL_TO_SURFACE)
230            }
231            Code::PromptVariantExplosion => Some(&REPAIR_MANUAL_NEEDS_HUMAN),
232
233            // --- STD: stdlib usage ----------------------------------------
234            Code::DeprecatedStdlibSymbol => Some(&REPAIR_STDLIB_MIGRATE_RENAMED),
235            Code::LintMissingStdlibMetadata => Some(&REPAIR_DOC_ADD_STDLIB_METADATA),
236
237            // --- OWN: ownership & mutability ------------------------------
238            Code::ImmutableAssignment => Some(&REPAIR_BINDINGS_MAKE_MUTABLE),
239            Code::MutableNeverReassigned => Some(&REPAIR_BINDINGS_MAKE_IMMUTABLE),
240
241            // --- MAT: match exhaustiveness --------------------------------
242            Code::NonExhaustiveMatch => Some(&REPAIR_MATCH_ADD_MISSING_ARMS),
243            Code::DuplicateMatchArm => Some(&REPAIR_MATCH_REMOVE_DUPLICATE_ARM),
244
245            // --- ORC: orchestration ---------------------------------------
246            Code::UnreachableCode => Some(&REPAIR_DEAD_CODE_REMOVE),
247
248            // --- FMT: formatter -------------------------------------------
249            Code::FormatterWouldReformat | Code::FormatterTrailingComma => {
250                Some(&REPAIR_FORMAT_REFORMAT)
251            }
252
253            // --- LNT: lints with structured fixes -------------------------
254            Code::LintUnusedVariable
255            | Code::LintUnusedPatternBinding
256            | Code::LintUnusedParameter => Some(&REPAIR_BINDINGS_RENAME_UNUSED),
257            Code::LintCapabilityParameterName => Some(&REPAIR_BINDINGS_NAME_CAPABILITY_PARAMETER),
258            Code::LintUnusedImport => Some(&REPAIR_IMPORTS_REMOVE_UNUSED),
259            Code::LintUnusedFunction | Code::LintUnusedType => {
260                Some(&REPAIR_DECLARATIONS_REMOVE_UNUSED)
261            }
262            Code::LintMutableNeverReassigned => Some(&REPAIR_BINDINGS_MAKE_IMMUTABLE),
263            Code::LintImportOrder => Some(&REPAIR_IMPORTS_REORDER),
264            Code::LintBlankLineBetweenItems
265            | Code::LintTrailingComma
266            | Code::LintUnnecessaryParentheses
267            | Code::LintRequireFileHeader => Some(&REPAIR_FORMAT_REFORMAT),
268            Code::LintLegacyDocComment => Some(&REPAIR_DOC_COMMENT_MIGRATE),
269            Code::LintEmptyBlock => Some(&REPAIR_BLOCK_REMOVE_EMPTY),
270            Code::LintUnnecessaryElseReturn | Code::LintLetThenReturn => {
271                Some(&REPAIR_CONTROL_FLOW_FLATTEN)
272            }
273            Code::LintNilCoalesceNoop
274            | Code::LintNilCoalesceSelfFallback
275            | Code::LintRedundantNilTernary
276            | Code::LintUnnecessarySafeNavigation
277            | Code::LintUnnecessaryNonNullAssert
278            | Code::LintPreferOptionalShorthand
279            | Code::LintComparisonToBool
280            | Code::LintPointlessComparison
281            | Code::LintConstantLogicalOperand => Some(&REPAIR_EXPRESSION_SIMPLIFY),
282            Code::LintUnnecessaryCast => Some(&REPAIR_CASTS_REMOVE_REDUNDANT),
283            Code::LintRedundantClone => Some(&REPAIR_CLONE_REMOVE_REDUNDANT),
284            Code::LintEagerCollectionConversion => Some(&REPAIR_COLLECTION_PREFER_LAZY),
285            Code::LintDeadCodeAfterReturn => Some(&REPAIR_DEAD_CODE_REMOVE),
286            Code::LintRenamedStdlibSymbol => Some(&REPAIR_STDLIB_MIGRATE_RENAMED),
287            Code::LintAmbientClockBuiltin => Some(&REPAIR_BINDINGS_THREAD_HARNESS_CLOCK),
288            Code::LintAmbientFsBuiltin => Some(&REPAIR_BINDINGS_THREAD_HARNESS_FS),
289            Code::LintAmbientEnvBuiltin => Some(&REPAIR_BINDINGS_THREAD_HARNESS_ENV),
290            Code::LintAmbientRandomBuiltin => Some(&REPAIR_BINDINGS_THREAD_HARNESS_RANDOM),
291            Code::LintAmbientNetBuiltin => Some(&REPAIR_BINDINGS_THREAD_HARNESS_NET),
292            Code::LintAmbientStdioBuiltin => Some(&REPAIR_BINDINGS_THREAD_HARNESS),
293            Code::LintAmbientHarnessMethod => Some(&REPAIR_BINDINGS_THREAD_HARNESS_METHOD),
294            Code::LintBroadHarnessParameter => Some(&REPAIR_BINDINGS_ATTENUATE_HARNESS),
295            Code::LintDeprecatedLlmOptions => Some(&REPAIR_LLM_MIGRATE_DEPRECATED_OPTION),
296            Code::LintTemplateProviderIdentityBranch => Some(&REPAIR_LLM_USE_CAPABILITY_FLAG),
297            Code::LintPromptInjectionRisk => Some(&REPAIR_PROMPTS_ESCAPE_INJECTION),
298            Code::LintShadowVariable => Some(&REPAIR_BINDINGS_RENAME_SHADOW),
299            Code::LintNamingConvention => Some(&REPAIR_STYLE_RENAME_TO_CONVENTION),
300            Code::LintUnhandledApprovalResult => Some(&REPAIR_ERRORS_CHECK_OR_RESCUE),
301            Code::LintMissingHarndoc => Some(&REPAIR_DOC_ADD_HARNDOC),
302            Code::LintDuplicateMatchArm => Some(&REPAIR_MATCH_REMOVE_DUPLICATE_ARM),
303            // HARN-LNT-029 is the lint face of the boundary-validation rule, so
304            // its repair has to validate. HARN-LNT-060 below is a different
305            // complaint — an inline options dict bypassing the typed option
306            // constructors — where naming the shape is the whole fix and no
307            // untrusted payload is involved.
308            Code::LintUntypedDictAccess => Some(&REPAIR_TYPES_VALIDATE_BOUNDARY_VALUE),
309            Code::LintUnnormalizedOptions => Some(&REPAIR_TYPES_ADD_SHAPE_ANNOTATION),
310            Code::LintMcpToolAnnotations => Some(&REPAIR_MANUAL_NEEDS_HUMAN),
311            Code::LintTemplateVariantExplosion | Code::LintLongRunningWithoutCleanup => {
312                Some(&REPAIR_MANUAL_NEEDS_HUMAN)
313            }
314
315            // Everything else: no statically known repair shape. Agents
316            // should treat these as "diagnose only" until a repair is
317            // registered.
318            _ => None,
319        }
320    }
321}
322
323// Repair-id catalog. Each `RepairTemplate` carries a kebab-case
324// namespaced id (`<namespace>/<verb-noun>`), a one-line summary written
325// in the imperative voice, and a `RepairSafety` class.
326//
327// Conventions:
328//   - Namespaces stay short: `bindings/`, `imports/`, `errors/`, `casts/`,
329//     `format/`, `llm/`, `prompts/`, `match/`, `stdlib/`, `lint/`,
330//     `doc/`, `style/`, `types/`, `manual/`.
331//   - Summary starts with a verb ("Replace…", "Remove…", "Insert…").
332//   - Safety must be the most permissive class that is still always true
333//     for every site this template attaches to. When unsure, pick the
334//     stricter class — agents tighten too-loose policies later, never
335//     too-tight ones.
336
337const REPAIR_INSERT_EXPLICIT_CONVERSION: RepairTemplate = RepairTemplate {
338    id: "casts/insert-explicit-conversion",
339    summary: "Insert an explicit conversion or correct the operand type",
340    safety: RepairSafety::ScopeLocal,
341};
342
343const REPAIR_REWRITE_STRING_INTERPOLATION: RepairTemplate = RepairTemplate {
344    id: "style/string-interpolation",
345    summary: "Rewrite string concatenation as an interpolation literal",
346    safety: RepairSafety::BehaviorPreserving,
347};
348
349const REPAIR_CASTS_REMOVE_UNCHECKED: RepairTemplate = RepairTemplate {
350    id: "casts/remove-unchecked",
351    summary: "Remove the unchecked cast or guard it with a type test",
352    safety: RepairSafety::ScopeLocal,
353};
354
355const REPAIR_CASTS_REMOVE_REDUNDANT: RepairTemplate = RepairTemplate {
356    id: "casts/remove-redundant",
357    summary: "Remove the redundant cast",
358    safety: RepairSafety::BehaviorPreserving,
359};
360
361const REPAIR_BINDINGS_RENAME_TO_CLOSEST: RepairTemplate = RepairTemplate {
362    id: "bindings/rename-to-closest",
363    summary: "Rename to the closest in-scope identifier",
364    safety: RepairSafety::ScopeLocal,
365};
366
367const REPAIR_BINDINGS_MAKE_MUTABLE: RepairTemplate = RepairTemplate {
368    id: "bindings/make-mutable",
369    summary: "Declare the binding with `let` so it can be reassigned",
370    safety: RepairSafety::ScopeLocal,
371};
372
373const REPAIR_BINDINGS_MAKE_IMMUTABLE: RepairTemplate = RepairTemplate {
374    id: "bindings/make-immutable",
375    summary: "Declare the never-reassigned binding with `const` instead of `let`",
376    safety: RepairSafety::BehaviorPreserving,
377};
378
379const REPAIR_BINDINGS_RENAME_UNUSED: RepairTemplate = RepairTemplate {
380    id: "bindings/rename-unused",
381    summary: "Mark an unused binding without changing callable arity",
382    safety: RepairSafety::BehaviorPreserving,
383};
384
385const REPAIR_BINDINGS_NAME_CAPABILITY_PARAMETER: RepairTemplate = RepairTemplate {
386    id: "bindings/name-capability-parameter",
387    summary: "Rename the capability parameter and its references after the capability it carries",
388    safety: RepairSafety::SurfaceChanging,
389};
390
391const REPAIR_BINDINGS_RENAME_SHADOW: RepairTemplate = RepairTemplate {
392    id: "bindings/rename-shadow",
393    summary: "Rename the shadowing binding to a distinct name",
394    safety: RepairSafety::ScopeLocal,
395};
396
397const REPAIR_BINDINGS_THREAD_HARNESS: RepairTemplate = RepairTemplate {
398    id: "bindings/thread-harness",
399    summary: "Thread the existing `harness` binding through local helper calls and replace the ambient stdio builtin with `harness.stdio.*`",
400    safety: RepairSafety::ScopeLocal,
401};
402
403const REPAIR_BINDINGS_THREAD_HARNESS_NEEDS_PARAM: RepairTemplate = RepairTemplate {
404    id: "bindings/thread-harness-needs-param",
405    summary: "Add a `harness: Harness` parameter where the stdio capability handle is required and update local callers",
406    safety: RepairSafety::SurfaceChanging,
407};
408
409const REPAIR_BINDINGS_THREAD_HARNESS_METHOD: RepairTemplate = RepairTemplate {
410    id: "bindings/thread-harness-method",
411    summary: "Replace the ambient runtime builtin with its typed `harness.*` method and thread authority through local callers",
412    safety: RepairSafety::ScopeLocal,
413};
414
415const REPAIR_BINDINGS_THREAD_HARNESS_CLOCK: RepairTemplate = RepairTemplate {
416    id: "bindings/thread-harness-clock",
417    summary: "Replace the ambient clock builtin with the corresponding `harness.clock.*` method",
418    safety: RepairSafety::ScopeLocal,
419};
420
421const REPAIR_BINDINGS_THREAD_HARNESS_FS: RepairTemplate = RepairTemplate {
422    id: "bindings/thread-harness-fs",
423    summary: "Replace the ambient fs builtin with the corresponding `harness.fs.*` method",
424    safety: RepairSafety::ScopeLocal,
425};
426
427const REPAIR_BINDINGS_THREAD_HARNESS_ENV: RepairTemplate = RepairTemplate {
428    id: "bindings/thread-harness-env",
429    summary: "Replace the ambient env builtin with the corresponding `harness.env.*` method",
430    safety: RepairSafety::ScopeLocal,
431};
432
433const REPAIR_BINDINGS_THREAD_HARNESS_RANDOM: RepairTemplate = RepairTemplate {
434    id: "bindings/thread-harness-random",
435    summary: "Replace the ambient random builtin with the corresponding `harness.random.*` method",
436    safety: RepairSafety::ScopeLocal,
437};
438
439const REPAIR_BINDINGS_THREAD_HARNESS_NET: RepairTemplate = RepairTemplate {
440    id: "bindings/thread-harness-net",
441    summary: "Replace the ambient net builtin with the corresponding `harness.net.*` method",
442    safety: RepairSafety::ScopeLocal,
443};
444
445const REPAIR_DECLARATIONS_REMOVE_UNUSED: RepairTemplate = RepairTemplate {
446    id: "declarations/remove-unused",
447    summary: "Remove the unused declaration",
448    safety: RepairSafety::SurfaceChanging,
449};
450
451const REPAIR_IMPORTS_FIX_PATH: RepairTemplate = RepairTemplate {
452    id: "imports/fix-path",
453    summary: "Replace the import path with a resolvable target",
454    safety: RepairSafety::ScopeLocal,
455};
456
457const REPAIR_IMPORTS_REMOVE_UNUSED: RepairTemplate = RepairTemplate {
458    id: "imports/remove-unused",
459    summary: "Remove the unused import",
460    safety: RepairSafety::BehaviorPreserving,
461};
462
463const REPAIR_IMPORTS_REORDER: RepairTemplate = RepairTemplate {
464    id: "imports/reorder",
465    summary: "Reorder imports into canonical grouping",
466    safety: RepairSafety::FormatOnly,
467};
468
469const REPAIR_ERRORS_CHECK_OR_RESCUE: RepairTemplate = RepairTemplate {
470    id: "errors/check-or-rescue",
471    summary: "Check the result or wrap the call in a `rescue` block",
472    safety: RepairSafety::ScopeLocal,
473};
474
475const REPAIR_ERRORS_WRAP_IN_FN: RepairTemplate = RepairTemplate {
476    id: "errors/wrap-in-fn",
477    summary: "Move the construct inside a function body",
478    safety: RepairSafety::SurfaceChanging,
479};
480
481const REPAIR_MATCH_ADD_MISSING_ARMS: RepairTemplate = RepairTemplate {
482    id: "match/add-missing-arms",
483    summary: "Add arms covering the missing variants",
484    safety: RepairSafety::ScopeLocal,
485};
486
487const REPAIR_MATCH_REMOVE_DUPLICATE_ARM: RepairTemplate = RepairTemplate {
488    id: "match/remove-duplicate-arm",
489    summary: "Remove the duplicated match arm",
490    safety: RepairSafety::BehaviorPreserving,
491};
492
493const REPAIR_FORMAT_REFORMAT: RepairTemplate = RepairTemplate {
494    id: "format/reformat",
495    summary: "Apply canonical formatting",
496    safety: RepairSafety::FormatOnly,
497};
498
499const REPAIR_DOC_COMMENT_MIGRATE: RepairTemplate = RepairTemplate {
500    id: "doc/migrate-comment-style",
501    summary: "Migrate the legacy comment to canonical doc syntax",
502    safety: RepairSafety::FormatOnly,
503};
504
505const REPAIR_DOC_ADD_HARNDOC: RepairTemplate = RepairTemplate {
506    id: "doc/add-harndoc",
507    summary: "Add a `///` doc comment describing this declaration",
508    safety: RepairSafety::BehaviorPreserving,
509};
510
511const REPAIR_DOC_ADD_STDLIB_METADATA: RepairTemplate = RepairTemplate {
512    id: "doc/add-stdlib-metadata",
513    summary: "Add `@effects` and `@errors` fields to the stdlib function's doc block",
514    safety: RepairSafety::BehaviorPreserving,
515};
516
517const REPAIR_BLOCK_REMOVE_EMPTY: RepairTemplate = RepairTemplate {
518    id: "blocks/remove-empty",
519    summary: "Remove the empty block or fill in an explicit body",
520    safety: RepairSafety::ScopeLocal,
521};
522
523const REPAIR_CONTROL_FLOW_FLATTEN: RepairTemplate = RepairTemplate {
524    id: "control-flow/flatten",
525    summary: "Flatten the unnecessary control flow construct",
526    safety: RepairSafety::BehaviorPreserving,
527};
528
529const REPAIR_EXPRESSION_SIMPLIFY: RepairTemplate = RepairTemplate {
530    id: "expressions/simplify",
531    summary: "Simplify the expression to its canonical form",
532    safety: RepairSafety::BehaviorPreserving,
533};
534
535const REPAIR_CLONE_REMOVE_REDUNDANT: RepairTemplate = RepairTemplate {
536    id: "clones/remove-redundant",
537    summary: "Remove the redundant clone",
538    safety: RepairSafety::BehaviorPreserving,
539};
540
541const REPAIR_COLLECTION_PREFER_LAZY: RepairTemplate = RepairTemplate {
542    id: "collections/prefer-lazy",
543    summary: "Replace the eager collection step with a lazy variant",
544    safety: RepairSafety::ScopeLocal,
545};
546
547const REPAIR_DEAD_CODE_REMOVE: RepairTemplate = RepairTemplate {
548    id: "control-flow/remove-dead",
549    summary: "Remove the unreachable code",
550    safety: RepairSafety::BehaviorPreserving,
551};
552
553const REPAIR_STDLIB_MIGRATE_RENAMED: RepairTemplate = RepairTemplate {
554    id: "stdlib/migrate-renamed",
555    summary: "Rename the call to the renamed stdlib symbol",
556    safety: RepairSafety::ScopeLocal,
557};
558
559const REPAIR_BINDINGS_ATTENUATE_HARNESS: RepairTemplate = RepairTemplate {
560    id: "bindings/attenuate-harness",
561    summary: "Replace the root Harness parameter with the single capability the helper uses",
562    safety: RepairSafety::SurfaceChanging,
563};
564
565const REPAIR_LLM_MIGRATE_DEPRECATED_OPTION: RepairTemplate = RepairTemplate {
566    id: "llm/migrate-deprecated-option",
567    summary: "Replace the deprecated option with its supported equivalent",
568    safety: RepairSafety::ScopeLocal,
569};
570
571const REPAIR_LLM_ADD_SCHEMA: RepairTemplate = RepairTemplate {
572    id: "llm/add-schema",
573    summary: "Add a typed output schema to the LLM call",
574    safety: RepairSafety::SurfaceChanging,
575};
576
577const REPAIR_LLM_USE_CAPABILITY_FLAG: RepairTemplate = RepairTemplate {
578    id: "llm/use-capability-flag",
579    summary: "Branch on a capability flag instead of provider identity",
580    safety: RepairSafety::CapabilityChanging,
581};
582
583const REPAIR_PROMPTS_ESCAPE_INJECTION: RepairTemplate = RepairTemplate {
584    id: "prompts/escape-injection",
585    summary: "Pass the untrusted input through a structured placeholder",
586    safety: RepairSafety::ScopeLocal,
587};
588
589const REPAIR_PROMPTS_ADD_TOOL_TO_SURFACE: RepairTemplate = RepairTemplate {
590    id: "prompts/add-tool-to-surface",
591    summary: "Add the referenced tool to the declared tool surface",
592    safety: RepairSafety::SurfaceChanging,
593};
594
595const REPAIR_STYLE_RENAME_TO_CONVENTION: RepairTemplate = RepairTemplate {
596    id: "style/rename-to-convention",
597    summary: "Rename to match the casing convention for this kind",
598    safety: RepairSafety::SurfaceChanging,
599};
600
601const REPAIR_TYPES_ADD_SHAPE_ANNOTATION: RepairTemplate = RepairTemplate {
602    id: "types/add-shape-annotation",
603    summary: "Annotate the dict with a concrete shape type",
604    safety: RepairSafety::SurfaceChanging,
605};
606
607/// The repair for a parameter that never got a type.
608///
609/// Surface-changing rather than scope-local: the annotation lands on a
610/// signature, and once it is there every caller is checked against it. That is
611/// the point of the repair, and it is also why it is not auto-applied under a
612/// lower ceiling. `harn fix` infers the type from the body and the call sites,
613/// so the mechanical part of the migration is covered; `unknown` is what it
614/// writes when it can prove nothing, preserving the need to narrow dynamic
615/// values before use.
616const REPAIR_TYPES_ANNOTATE_PARAMETER: RepairTemplate = RepairTemplate {
617    id: "types/annotate-parameter",
618    summary: "Annotate the parameter with the inferred type, or `unknown` and narrow it at the dynamic boundary",
619    safety: RepairSafety::SurfaceChanging,
620};
621
622/// The repair for a boundary value read without validation.
623///
624/// Since harn#6252 a binding annotation *is* enforced, so annotating a
625/// `json_parse` result does validate it — the original reason for keeping
626/// `types/add-shape-annotation` away from this rule (that the annotation was
627/// erased, and so removed the diagnostic without removing the hazard) no longer
628/// holds.
629///
630/// This still offers schema validation rather than the annotation, for a
631/// different and narrower reason: a binding assertion reports the declared type
632/// and the value's kind, while `schema_expect` reports which field failed and
633/// why. For an untrusted payload that difference is the whole diagnosis. The
634/// annotation is now a correct fix; it is not the most informative one, and a
635/// one-step automated repair should offer the most informative.
636const REPAIR_TYPES_VALIDATE_BOUNDARY_VALUE: RepairTemplate = RepairTemplate {
637    id: "types/validate-boundary-value",
638    summary: "Validate the parsed value with schema_expect() or schema_check() before reading it",
639    safety: RepairSafety::ScopeLocal,
640};
641
642const REPAIR_MANUAL_REVIEW_CAPABILITY: RepairTemplate = RepairTemplate {
643    id: "manual/review-capability-binding",
644    summary: "Review the capability binding; the fix is not mechanical",
645    safety: RepairSafety::NeedsHuman,
646};
647
648const REPAIR_POLICY_NARROW_CHILD_EFFECTS: RepairTemplate = RepairTemplate {
649    id: "policy/narrow-child-effects",
650    summary: "Narrow the child agent's effects to a subset of the parent's, or widen the parent's declared effects",
651    safety: RepairSafety::SurfaceChanging,
652};
653
654const REPAIR_MANUAL_NEEDS_HUMAN: RepairTemplate = RepairTemplate {
655    id: "manual/needs-human",
656    summary: "Plan a human-led change; auto-apply is not safe here",
657    safety: RepairSafety::NeedsHuman,
658};
659
660/// Every repair template registered by [`Code::repair_template`], in source
661/// order for catalog generation and health checks.
662pub const REPAIR_REGISTRY: &[&RepairTemplate] = &[
663    &REPAIR_INSERT_EXPLICIT_CONVERSION,
664    &REPAIR_REWRITE_STRING_INTERPOLATION,
665    &REPAIR_CASTS_REMOVE_UNCHECKED,
666    &REPAIR_CASTS_REMOVE_REDUNDANT,
667    &REPAIR_BINDINGS_RENAME_TO_CLOSEST,
668    &REPAIR_BINDINGS_MAKE_MUTABLE,
669    &REPAIR_BINDINGS_MAKE_IMMUTABLE,
670    &REPAIR_BINDINGS_RENAME_UNUSED,
671    &REPAIR_BINDINGS_NAME_CAPABILITY_PARAMETER,
672    &REPAIR_BINDINGS_RENAME_SHADOW,
673    &REPAIR_BINDINGS_THREAD_HARNESS,
674    &REPAIR_BINDINGS_THREAD_HARNESS_NEEDS_PARAM,
675    &REPAIR_BINDINGS_THREAD_HARNESS_METHOD,
676    &REPAIR_BINDINGS_THREAD_HARNESS_CLOCK,
677    &REPAIR_BINDINGS_THREAD_HARNESS_FS,
678    &REPAIR_BINDINGS_THREAD_HARNESS_ENV,
679    &REPAIR_BINDINGS_THREAD_HARNESS_RANDOM,
680    &REPAIR_BINDINGS_THREAD_HARNESS_NET,
681    &REPAIR_DECLARATIONS_REMOVE_UNUSED,
682    &REPAIR_IMPORTS_FIX_PATH,
683    &REPAIR_IMPORTS_REMOVE_UNUSED,
684    &REPAIR_IMPORTS_REORDER,
685    &REPAIR_ERRORS_CHECK_OR_RESCUE,
686    &REPAIR_ERRORS_WRAP_IN_FN,
687    &REPAIR_MATCH_ADD_MISSING_ARMS,
688    &REPAIR_MATCH_REMOVE_DUPLICATE_ARM,
689    &REPAIR_FORMAT_REFORMAT,
690    &REPAIR_DOC_COMMENT_MIGRATE,
691    &REPAIR_DOC_ADD_HARNDOC,
692    &REPAIR_DOC_ADD_STDLIB_METADATA,
693    &REPAIR_BLOCK_REMOVE_EMPTY,
694    &REPAIR_CONTROL_FLOW_FLATTEN,
695    &REPAIR_EXPRESSION_SIMPLIFY,
696    &REPAIR_CLONE_REMOVE_REDUNDANT,
697    &REPAIR_COLLECTION_PREFER_LAZY,
698    &REPAIR_DEAD_CODE_REMOVE,
699    &REPAIR_STDLIB_MIGRATE_RENAMED,
700    &REPAIR_BINDINGS_ATTENUATE_HARNESS,
701    &REPAIR_LLM_MIGRATE_DEPRECATED_OPTION,
702    &REPAIR_LLM_ADD_SCHEMA,
703    &REPAIR_LLM_USE_CAPABILITY_FLAG,
704    &REPAIR_PROMPTS_ESCAPE_INJECTION,
705    &REPAIR_PROMPTS_ADD_TOOL_TO_SURFACE,
706    &REPAIR_STYLE_RENAME_TO_CONVENTION,
707    &REPAIR_TYPES_ADD_SHAPE_ANNOTATION,
708    &REPAIR_TYPES_ANNOTATE_PARAMETER,
709    &REPAIR_TYPES_VALIDATE_BOUNDARY_VALUE,
710    &REPAIR_MANUAL_REVIEW_CAPABILITY,
711    &REPAIR_MANUAL_NEEDS_HUMAN,
712    &REPAIR_POLICY_NARROW_CHILD_EFFECTS,
713];
714
715#[cfg(test)]
716mod tests {
717    use super::super::Category;
718    use super::{Code, ParseRepairSafetyError, RepairSafety, REPAIR_REGISTRY};
719    use std::collections::HashSet;
720    use std::str::FromStr;
721
722    #[test]
723    fn parses_registered_code() {
724        assert_eq!(Code::from_str("HARN-TYP-014"), Ok(Code::TypeParameterArity));
725    }
726
727    #[test]
728    fn registry_has_unique_identifiers() {
729        let mut seen = HashSet::new();
730        for entry in Code::registry() {
731            assert!(
732                seen.insert(entry.identifier),
733                "duplicate diagnostic code {}",
734                entry.identifier
735            );
736            assert_eq!(entry.code.as_str(), entry.identifier);
737            assert_eq!(entry.code.category(), entry.category);
738            let expected_prefix = format!("HARN-{}-", entry.category);
739            assert!(entry.identifier.starts_with(&expected_prefix));
740            let suffix = entry.identifier.trim_start_matches(&expected_prefix);
741            assert_eq!(suffix.len(), 3);
742            assert!(suffix.chars().all(|ch| ch.is_ascii_digit()));
743            assert!(!entry.summary.is_empty());
744        }
745        assert!(Code::registry().len() >= 40);
746    }
747
748    #[test]
749    fn every_category_is_populated() {
750        for category in Category::ALL {
751            assert!(
752                Code::registry()
753                    .iter()
754                    .any(|entry| entry.category == *category),
755                "missing diagnostic code category {category}"
756            );
757        }
758    }
759
760    #[test]
761    fn every_code_has_non_empty_explanation() {
762        for entry in Code::registry() {
763            let body = entry.code.explanation();
764            assert!(
765                !body.trim().is_empty(),
766                "diagnostic code {} has an empty explanation file",
767                entry.identifier
768            );
769            assert!(
770                body.contains(entry.identifier),
771                "explanation for {} should reference its identifier",
772                entry.identifier
773            );
774        }
775    }
776
777    #[test]
778    fn related_codes_are_registered_and_non_self() {
779        for entry in Code::registry() {
780            for &other in entry.code.related() {
781                assert_ne!(
782                    other, entry.code,
783                    "{} lists itself as a related code",
784                    entry.identifier
785                );
786                assert!(
787                    Code::registry().iter().any(|e| e.code == other),
788                    "{} lists unregistered related code {}",
789                    entry.identifier,
790                    other
791                );
792            }
793        }
794    }
795
796    #[test]
797    fn repair_safety_string_roundtrip() {
798        for safety in RepairSafety::ALL {
799            let parsed = RepairSafety::from_str(safety.as_str()).unwrap();
800            assert_eq!(parsed, *safety);
801            assert_eq!(parsed.to_string(), safety.as_str());
802        }
803        assert_eq!(
804            RepairSafety::from_str("not-a-safety-class"),
805            Err(ParseRepairSafetyError)
806        );
807    }
808
809    #[test]
810    fn repair_safety_ordering_is_monotonic_low_to_high() {
811        // The is_at_most ceiling check relies on this ordering being
812        // least-to-most disruptive; a regression here flips the meaning
813        // of `harn fix --safety <ceiling>` for every caller.
814        let order = RepairSafety::ALL;
815        for window in order.windows(2) {
816            assert!(
817                window[0] < window[1],
818                "{:?} should be safer than {:?}",
819                window[0],
820                window[1]
821            );
822            assert!(window[0].is_at_most(window[1]));
823            assert!(!window[1].is_at_most(window[0]));
824        }
825    }
826
827    #[test]
828    fn repair_registry_has_at_least_twenty_entries() {
829        assert!(
830            REPAIR_REGISTRY.len() >= 20,
831            "expected ≥20 repair templates, found {}",
832            REPAIR_REGISTRY.len()
833        );
834    }
835
836    #[test]
837    fn repair_ids_are_kebab_case_namespaced_and_unique() {
838        let mut seen = HashSet::new();
839        for template in REPAIR_REGISTRY {
840            assert!(
841                seen.insert(template.id),
842                "duplicate repair id {}",
843                template.id
844            );
845            let (namespace, leaf) = template.id.split_once('/').unwrap_or_else(|| {
846                panic!(
847                    "repair id `{}` is missing `<namespace>/` prefix",
848                    template.id
849                )
850            });
851            assert!(
852                !namespace.is_empty() && !leaf.is_empty(),
853                "repair id `{}` has empty namespace or leaf",
854                template.id
855            );
856            for ch in template.id.chars() {
857                assert!(
858                    ch.is_ascii_lowercase() || ch.is_ascii_digit() || ch == '-' || ch == '/',
859                    "repair id `{}` has non-kebab character {ch:?}",
860                    template.id
861                );
862            }
863            assert!(
864                !template.summary.is_empty(),
865                "repair {} has empty summary",
866                template.id
867            );
868            // Summaries are imperative: start with a capital ASCII letter.
869            let first = template.summary.chars().next().unwrap();
870            assert!(
871                first.is_ascii_uppercase(),
872                "repair {} summary `{}` should start with a capital",
873                template.id,
874                template.summary
875            );
876        }
877    }
878
879    #[test]
880    fn manual_namespace_is_needs_human() {
881        for template in REPAIR_REGISTRY {
882            if let Some(("manual", _)) = template.id.split_once('/') {
883                assert_eq!(
884                    template.safety,
885                    RepairSafety::NeedsHuman,
886                    "manual/* repair {} must be NeedsHuman",
887                    template.id
888                );
889            }
890        }
891    }
892
893    #[test]
894    fn known_codes_carry_expected_safety_class() {
895        // Spot-check: the autonomy contract for several representative
896        // diagnostics. Lock in the safety class so cross-repo agents that
897        // dispatch on these don't silently drift when the catalog moves.
898        let expected: &[(Code, RepairSafety, &str)] = &[
899            (
900                Code::FormatterWouldReformat,
901                RepairSafety::FormatOnly,
902                "format/reformat",
903            ),
904            (
905                Code::ModuleImportUnused,
906                RepairSafety::BehaviorPreserving,
907                "imports/remove-unused",
908            ),
909            (
910                Code::ImmutableAssignment,
911                RepairSafety::ScopeLocal,
912                "bindings/make-mutable",
913            ),
914            (
915                Code::LintUnusedFunction,
916                RepairSafety::SurfaceChanging,
917                "declarations/remove-unused",
918            ),
919            (
920                Code::LlmProviderIdentityBranch,
921                RepairSafety::CapabilityChanging,
922                "llm/use-capability-flag",
923            ),
924            (
925                Code::PromptVariantExplosion,
926                RepairSafety::NeedsHuman,
927                "manual/needs-human",
928            ),
929            (
930                Code::NonExhaustiveMatch,
931                RepairSafety::ScopeLocal,
932                "match/add-missing-arms",
933            ),
934            (
935                Code::LintAmbientClockBuiltin,
936                RepairSafety::ScopeLocal,
937                "bindings/thread-harness-clock",
938            ),
939            (
940                Code::LintAmbientStdioBuiltin,
941                RepairSafety::ScopeLocal,
942                "bindings/thread-harness",
943            ),
944            (
945                Code::InvalidMainSignature,
946                RepairSafety::SurfaceChanging,
947                "bindings/thread-harness-needs-param",
948            ),
949        ];
950        for (code, safety, repair_id) in expected {
951            let template = code
952                .repair_template()
953                .unwrap_or_else(|| panic!("{code} should have a repair template"));
954            assert_eq!(template.safety, *safety, "{code} safety class drifted");
955            assert_eq!(template.id, *repair_id, "{code} repair id drifted");
956        }
957    }
958
959    #[test]
960    fn repair_templates_cover_at_least_twenty_codes() {
961        let covered = Code::ALL
962            .iter()
963            .filter(|code| code.repair_template().is_some())
964            .count();
965        assert!(
966            covered >= 20,
967            "expected ≥20 codes with a repair template, found {covered}"
968        );
969    }
970
971    /// A rule about validating a boundary value cannot be repaired by an
972    /// annotation.
973    ///
974    /// An annotation is erased before the value exists: annotating a
975    /// `json_parse` result reads an int out of a field declared `string` and
976    /// accepts an array as a record, with no diagnostic at either compile time
977    /// or run time. Offering it as the one-step repair for these codes would
978    /// auto-apply the escape the codes exist to close, and a repair is applied
979    /// more readily than help text is read (harn#6234).
980    ///
981    /// `LintUnnormalizedOptions` is deliberately not in this list. It is about
982    /// an inline options dict bypassing the typed option constructors, where no
983    /// untrusted payload is involved and naming the shape is the whole fix.
984    #[test]
985    fn boundary_validation_codes_offer_the_most_informative_repair() {
986        for code in [Code::BoundaryValueUnvalidated, Code::LintUntypedDictAccess] {
987            let Some(template) = code.repair_template() else {
988                continue;
989            };
990            assert_ne!(
991                template.id, "types/add-shape-annotation",
992                "{code:?} is a boundary-validation rule; an annotation validates the value \
993                 (harn#6252) but reports only the declared type and the value's kind, so the \
994                 offered one-step repair must be the one that names the failing field"
995            );
996        }
997    }
998
999    #[test]
1000    fn every_registered_repair_is_referenced_by_some_code() {
1001        let referenced: HashSet<&'static str> = Code::ALL
1002            .iter()
1003            .filter_map(|code| code.repair_template())
1004            .map(|template| template.id)
1005            .collect();
1006        for template in REPAIR_REGISTRY {
1007            assert!(
1008                referenced.contains(template.id),
1009                "repair {} is in REPAIR_REGISTRY but no Code maps to it",
1010                template.id
1011            );
1012        }
1013    }
1014
1015    #[test]
1016    fn every_referenced_repair_template_is_in_registry() {
1017        let registered: HashSet<&'static str> =
1018            REPAIR_REGISTRY.iter().map(|template| template.id).collect();
1019        for code in Code::ALL {
1020            let Some(template) = code.repair_template() else {
1021                continue;
1022            };
1023            assert!(
1024                registered.contains(template.id),
1025                "repair {} (used by {}) is missing from REPAIR_REGISTRY",
1026                template.id,
1027                code
1028            );
1029        }
1030    }
1031}
harn_parser/diagnostic_codes/repairs.rs

harn_parser/diagnostic_codes/
repairs.rs
