ErrLookup › astral-sh/ruff
astral-sh/ruff
An extremely fast Python linter and code formatter, written in Rust. · Rust · 2,843 source files
Analyzed at 5bb508f594 on 2026-09-19. 303 documented errors.
| Code / Message | Type | Severity | Tags |
|---|---|---|---|
| every BDD constraint should have a source-order entry | panic | critical | ty, type-inference, constraint-solver, bdd, source-order, panic, ice, rust |
| `parsed_module` should have assigned a node index | panic | critical | ty, diagnostics, autofix, ast-node-index, final-method, panic, ice, rust |
| Expected simple statement to be an assert | exception | error | |
| clause vector should not be empty | panic | critical | ty, constraint-solver, bdd, dnf, backtracking, panic, ice, rust |
| Could not find the ruff binary in any of the following… | exception | error | python, pip, packaging, binary, installation, ruff |
| Mandatory `value_type` field is missing in `#[option]`… | exception | error | |
| The system does not support writing files | exception | error | io, rust, read-only, unsupported, ty, write |
| Virtual path does not exist | exception | error | |
| dynamic class definitions should only be used for… | panic | error | rust, panic, expect, ty, dynamic-class, source-span, invariant |
| A new type index cannot be generic. | exception | error | |
| Mandatory `example` field is missing in `#[option]`… | exception | error | |
| prefix has already been defined before | exception | error | |
| unexpected annotation type | panic | error | diagnostics, rendering, panic, multiline-annotation, annotate-snippets |
| Expected live-declarations length to fit into a u32 | panic | error | rust, ty, use-def, panic, integer-overflow, internal-invariant |
| Variable-length arguments are not supported | exception | info | ruff, flake8-pytest-style, autofix, unittest |
| Unable to parse filename | panic | error | |
| binding definition should have retained declarations | panic | error | rust, ty, use-def, panic, definition-classification, internal-invariant |
| Implement Ipy escape command support | panic | critical | ty, typechecker, notebook, ipython, panic, unimplemented |
| Could not find mdtest executable after successful… | exception | error | mdtest, cargo, testing, ty, python-tooling |
| Expected a Title | panic | error | diagnostics, rendering, panic, title, annotate-snippets |
| Expected CmpOp::Is | CmpOp::IsNot | panic | error | rust, panic, ruff, pyflakes, f632, internal-invariant |
| invalid default warning pattern | panic | error | rust, panic, configuration, flake8-pytest-style |
| Compound statement cannot be inlined | exception | warning | ruff, autofix, indentation, flake8-return |
| anchor should not be NodeIndex::NONE | panic | error | rust, panic, expect, ty, dynamic-class, node-index, invariant |
-32603 request handler | error_code | error | lsp, internal-error, panic, rust |
NotFound failed to resolve uv executable | error_code | error | ty, uv, path, executable-not-found, environment |
| Missing argument `first` | exception | error | linter, rust, pytest-style, argument-missing |
| extra use-def data should have been retained | panic | error | rust, ty, use-def, panic, stale-state, internal-invariant |
| `find_name_in_mro` should return `Some` for a class literal | panic | error | rust, ty, types, mro, member-lookup, typeshed, panic |
| Binding must have a statement to convert into a list… | exception | warning | ruff, autofix, perflint, list-comprehension |
| Annotation range ` ` is beyond the end of buffer | panic | error | diagnostics, rendering, panic, span, out-of-range |
| Server notebook document could not be converted to ty's… | panic | critical | notebook, lsp, panic, jupyter, serde |
| TypedDict code generation should use a TypedDict instance | panic | error | rust, panic, expect, ty, typeddict, classification, invariant |
| Workspace URI is not a file path | error_code | error | lsp, workspace, uri, file-path |
| Brackets are not balanced for type | validation | error | codegen, python, rust-ast, developer-tooling |
| Cannot find `:` in `else` statement | exception | error | linter, autofix, rust, tokenizer, flake8-return |
| ParamSpec sub-call should only contain a single… | panic | error | rust, ty, call-inference, paramspec, union, panic |
| File name should be non-null because path is guaranteed to… | panic | critical | site-packages, filesystem, panic, environment |
| Missing #[prefix = "..."] attribute | exception | error | proc-macro, compile-time, rust, attribute |
| Expected Stmt::ImportFrom | panic | error | rust, panic, ruff, lint-fix, internal-invariant |
| ValueValidation | validation | error | cli, config, toml |
| client exited without proper shutdown sequence | exception | warning | lsp, shutdown, protocol |
InternalError Notebook document expected from notebook source kind | exception | error | lsp, ruff-server, notebook, internal-error, state-desync |
| System should be writable | panic | error | rust, ty, ruff-db, fixes, filesystem, system-abstraction |
| checked bindings are stable across fixpoint iterations | panic | error | rust, ty, call-inference, overloads, fixpoint, nondeterminism, panic |
| `python_extension` is not expected to be combined with the… | panic | error | lsp, configuration, panic, vscode, server |
| Unknown keyword argument | exception | info | ruff, flake8-pytest-style, autofix, keyword-arguments |
| Patch span ` ` is beyond the end of buffer | panic | error | diagnostics, rendering, panic, patch, diff, out-of-range |
| accumulator should not be empty | panic | error | rust, panic, expect, ty, constraints, accumulator, algorithm, unreachable |
| Expected Stmt::Import | Stmt::ImportFrom | panic | error | rust, panic, ruff, isort, internal-invariant |
| Can't use built-in ` ` constructor | exception | info | ruff, refurb, autofix, shadowing |
| Boolean conversion is not supported for union | validation | warning | python, type-checking, ty, union-type, bool-conversion |
| DynamicClassAnchor::Definition should only be used for… | panic | error | rust, panic, expect, ty, dynamic-class, definition, invariant |
| last_target should have a corresponding entry | panic | error | rust, panic, invariant, flake8-simplify |
| running commands is not supported by this system | exception | error | uv, platform, subprocess, unsupported |
| Will return Some() when called on class literal | panic | error | rust, panic, expect, ty, typeddict, typeshed, member-lookup |
| Should only ever pass a positive integer to… | panic | error | rust, ty, subscript, panic, negative-index |
| No edits to make | exception | info | ruff, autofix, pyflakes, unused-import |
| typevar should be interned before ordering | panic | error | rust, panic, expect, ty, constraints, typevar, interning, ordering |
| uv synchronization worker terminated unexpectedly | exception | error | uv, worker, ipc, broken-pipe |
| Expected a ty `File`, found a ruff `SourceFile` | panic | error | diagnostics, ty, ruff, panic, file-handling |
| Received exit notification before a shutdown request | error_code | error | lsp, lifecycle, shutdown, protocol |
| string annotation offset should point to ExprStringLiteral | panic | error | rust, panic, expect, ty, dynamic-class, string-annotation, node-index |
| expected doc attribute to be in the form of #[doc = "..."] | exception | error | proc-macro, compile-time, rust, attribute-parsing |
| {err} | error_code | error | lsp, anyhow, error-handling, server |
| module to include at least one segment | panic | info | rust, panic, isort, invariant |
| tried to get QoS of thread which has opted out of QoS | panic | critical | macos, qos, threads, panic, lsp |
| Expected `NamedTuple` definition to be an assignment | panic | error | rust, panic, expect, ty, namedtuple, dynamic-class, definition |
| Unable to fix multiline statement | exception | info | ruff, flake8-simplify, sim117, autofix |
| Expected at least one reference | panic | error | rust, panic, empty-collection, flake8-type-checking |
| storage-free owned constraint sets must have terminal roots | panic | error | rust, panic, expect, ty, constraints, owned-set, merge, invariant |
| indented block to start with indentation | exception | warning | ruff, autofix, pylint, indentation, elif |
| Expected ScopeKind::Function | panic | error | rust, panic, ruff, pep8-naming, internal-invariant |
| Cannot insert `TYPE_CHECKING` block inline | exception | error | autofix, imports, typing, ruff |
| matched `Type::Divergent` above | panic | error | rust, ty, types, negation, divergent, panic |
| TypedDictParams should be available for… | panic | error | rust, panic, expect, ty, typeddict, classification, fields |
| Expected Expression::Tuple | Expression::List | exception | warning | rust, ruff, lint-autofix, flake8-comprehensions |
| `object` should always be a non-generic class in typeshed | panic | error | rust, panic, expect, ty, typeshed, environment, object |
| every TDD constraint should have a source order | panic | error | rust, panic, expect, ty, constraints, tdd, source-order, determinism |
| PySourceType always parses into a module | panic | critical | rust, panic, parser, invariant, internal |
| JSON parsing failure | error_code | error | lsp, json, serialization, invalid-params |
| Required import `from collections.abc import Set` specified… | validation | error | |
| tried to set QoS of thread which has opted out of QoS | panic | critical | macos, qos, threads, panic, lsp |
| non-terminal BDD should have source_order | panic | error | rust, panic, expect, ty, constraints, bdd, source-order, invariant |
| stream did not contain valid UTF-8 | error_code | error | filesystem, memory-fs, utf8, encoding |
| Expected one inner if statement | exception | info | ruff, flake8-simplify, sim102, autofix |
| Text document path does not point to a text document | exception | error | lsp, document-sync, notebook, server |
| Expected ScopeKind::Function | ScopeKind::Lambda | panic | error | rust, panic, ruff, unused-arguments, internal-invariant |
| Failed to send notification | console | error | lsp, channel, transport, shutdown, ruff-server |
| `uv sync` failed to run with exit code | console | error | subprocess, uv, environment-setup, cli |
| argument index should not be out of range | panic | error | rust, ty, diagnostics, call-arguments, index-out-of-bounds, panic |
| there must be a first type if there are conflicting types | panic | error | rust, ty, places, declared-types, panic, builder-invariant |
| Expected live-bindings length to fit into a u32 | panic | error | internal, invariant, panic, integer-overflow, data-structure |
| Invalid collection element type | validation | error | codegen, rust-ast, nested-generics, developer-tooling |
| `isinstance` should have two arguments | panic | error | rust, panic, ast, flake8-simplify |
| invalid default exception pattern | panic | critical | rust, panic, flake8-pytest-style, settings, default-config |
| Expected to handle named fields | panic | error | rust, proc-macro, configuration, named-fields |
| node should be non-terminal | panic | error | rust, panic, expect, ty, constraints, bdd, storage, invariant |
| expected doc comment to be in the form of `///… | exception | error | proc-macro, compile-time, rust, markdown |
| Expected : pattern | validation | error | cli, per-file-ignores, argument-parsing, ruff-linter |