derive Copy where possible (#6844)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Chores**
* Made many lightweight/internal types trivially copyable to simplify
value handling across the codebase.
* Added a workspace lint to surface missing copy implementations as
warnings.
  * Extended buffer support with explicit retain/release hooks.

* **Bug Fixes**
* Improved diagnostics and debug output for thread/lock acquisition
scenarios.

<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Cargo.toml

@@ -222,6 +222,7 @@ wasm-bindgen = "0.2.106"
 unsafe_code = "allow"
 unsafe_op_in_unsafe_fn = "deny"
 elided_lifetimes_in_paths = "warn"
+missing_copy_implementations = "warn"
 
 [workspace.lints.clippy]
 # alloc_instead_of_core = "warn"

crates/codegen/src/compile.rs

@@ -113,13 +113,14 @@ struct Compiler {
     in_annotation: bool,
 }
 
+#[derive(Clone, Copy)]
 enum DoneWithFuture {
     No,
     DoneWithDoc,
     Yes,
 }
 
-#[derive(Debug, Clone)]
+#[derive(Clone, Copy, Debug)]
 pub struct CompileOpts {
     /// How optimized the bytecode output should be; any optimize > 0 does
     /// not emit assert statements

crates/codegen/src/error.rs

@@ -3,7 +3,7 @@ use core::fmt::Display;
 use rustpython_compiler_core::SourceLocation;
 use thiserror::Error;
 
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub enum PatternUnreachableReason {
     NameCapture,
     Wildcard,

crates/codegen/src/ir.rs

@@ -85,7 +85,7 @@ impl ops::IndexMut<BlockIdx> for Vec<Block> {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Clone, Copy, Debug)]
 pub struct InstructionInfo {
     pub instr: AnyInstruction,
     pub arg: OpArg,
@@ -95,8 +95,8 @@ pub struct InstructionInfo {
     pub except_handler: Option<ExceptHandlerInfo>,
 }
 
-/// Exception handler information for an instruction
-#[derive(Debug, Clone)]
+/// Exception handler information for an instruction.
+#[derive(Clone, Copy, Debug)]
 pub struct ExceptHandlerInfo {
     /// Block to jump to when exception occurs
     pub handler_block: BlockIdx,
@@ -742,13 +742,13 @@ fn generate_exception_table(blocks: &[Block], block_to_index: &[u32]) -> Box<[u8
             // instr_size includes EXTENDED_ARG instructions
             let instr_size = instr.arg.instr_size() as u32;
 
-            match (&current_entry, &instr.except_handler) {
+            match (&current_entry, instr.except_handler) {
                 // No current entry, no handler - nothing to do
                 (None, None) => {}
 
                 // No current entry, handler starts - begin new entry
                 (None, Some(handler)) => {
-                    current_entry = Some((handler.clone(), instr_index));
+                    current_entry = Some((handler, instr_index));
                 }
 
                 // Current entry exists, same handler - continue
@@ -767,7 +767,7 @@ fn generate_exception_table(blocks: &[Block], block_to_index: &[u32]) -> Box<[u8
                         curr_handler.stack_depth as u16,
                         curr_handler.preserve_lasti,
                     ));
-                    current_entry = Some((handler.clone(), instr_index));
+                    current_entry = Some((handler, instr_index));
                 }
 
                 // Current entry exists, no handler - finish current entry

crates/codegen/src/symboltable.rs

@@ -758,7 +758,7 @@ impl SymbolTableAnalyzer {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Clone, Copy, Debug)]
 enum SymbolUsage {
     Global,
     Nonlocal,

crates/common/src/cformat.rs

@@ -14,7 +14,7 @@ use rustpython_literal::{float, format::Case};
 
 use crate::wtf8::{CodePoint, Wtf8, Wtf8Buf};
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum CFormatErrorType {
     UnmatchedKeyParentheses,
     MissingModuloSign,
@@ -27,7 +27,7 @@ pub enum CFormatErrorType {
 // also contains how many chars the parsing function consumed
 pub type ParsingError = (CFormatErrorType, usize);
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub struct CFormatError {
     pub typ: CFormatErrorType, // FIXME
     pub index: usize,

crates/common/src/encodings.rs

@@ -262,6 +262,7 @@ pub mod errors {
     use super::*;
     use core::fmt::Write;
 
+    #[derive(Clone, Copy)]
     pub struct Strict;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for Strict {
@@ -286,6 +287,7 @@ pub mod errors {
         }
     }
 
+    #[derive(Clone, Copy)]
     pub struct Ignore;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for Ignore {
@@ -310,6 +312,7 @@ pub mod errors {
         }
     }
 
+    #[derive(Clone, Copy)]
     pub struct Replace;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for Replace {
@@ -338,6 +341,7 @@ pub mod errors {
         }
     }
 
+    #[derive(Clone, Copy)]
     pub struct XmlCharRefReplace;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for XmlCharRefReplace {
@@ -358,6 +362,7 @@ pub mod errors {
         }
     }
 
+    #[derive(Clone, Copy)]
     pub struct BackslashReplace;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for BackslashReplace {
@@ -394,6 +399,7 @@ pub mod errors {
         }
     }
 
+    #[derive(Clone, Copy)]
     pub struct NameReplace;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for NameReplace {
@@ -422,6 +428,7 @@ pub mod errors {
         }
     }
 
+    #[derive(Clone, Copy)]
     pub struct SurrogateEscape;
 
     impl<Ctx: EncodeContext> EncodeErrorHandler<Ctx> for SurrogateEscape {

crates/common/src/fileutils.rs

@@ -46,7 +46,7 @@ pub mod windows {
 
     pub const SECS_BETWEEN_EPOCHS: i64 = 11644473600; // Seconds between 1.1.1601 and 1.1.1970
 
-    #[derive(Default)]
+    #[derive(Clone, Copy, Default)]
     pub struct StatStruct {
         pub st_dev: libc::c_ulong,
         pub st_ino: u64,
@@ -256,6 +256,7 @@ pub mod windows {
         m as _
     }
 
+    #[derive(Clone, Copy)]
     #[repr(C)]
     pub struct FILE_STAT_BASIC_INFORMATION {
         pub FileId: i64,
@@ -275,8 +276,9 @@ pub mod windows {
         pub FileId128: [u64; 2],
     }
 
-    #[repr(C)]
     #[allow(dead_code)]
+    #[derive(Clone, Copy)]
+    #[repr(C)]
     pub enum FILE_INFO_BY_NAME_CLASS {
         FileStatByNameInfo,
         FileStatLxByNameInfo,

crates/common/src/format.rs

@@ -110,7 +110,7 @@ impl FormatParse for FormatSign {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum FormatGrouping {
     Comma,
     Underscore,
@@ -136,7 +136,7 @@ impl From<&FormatGrouping> for char {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum FormatType {
     String,
     Binary,
@@ -199,7 +199,7 @@ impl FormatParse for FormatType {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub struct FormatSpec {
     conversion: Option<FormatConversion>,
     fill: Option<CodePoint>,
@@ -845,7 +845,7 @@ impl Deref for AsciiStr<'_> {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum FormatSpecError {
     DecimalDigitsTooMany,
     PrecisionTooBig,
@@ -862,7 +862,7 @@ pub enum FormatSpecError {
     NotImplemented(char, &'static str),
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum FormatParseError {
     UnmatchedBracket,
     MissingStartBracket,

crates/common/src/hash.rs

@@ -25,6 +25,7 @@ pub const SEED_BITS: usize = core::mem::size_of::<u64>() * 2 * 8;
 
 // pub const CUTOFF: usize = 7;
 
+#[derive(Clone, Copy)]
 pub struct HashSecret {
     k0: u64,
     k1: u64,

crates/common/src/int.rs

@@ -29,7 +29,7 @@ pub fn float_to_ratio(value: f64) -> Option<(BigInt, BigInt)> {
     })
 }
 
-#[derive(Debug, Eq, PartialEq)]
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum BytesToIntError {
     InvalidLiteral { base: u32 },
     InvalidBase,

crates/common/src/lock/cell_lock.rs

@@ -201,10 +201,14 @@ fn deadlock(lock_kind: &str, ty: &str) -> ! {
     panic!("deadlock: tried to {lock_kind}lock a Cell{ty} twice")
 }
 
+#[derive(Clone, Copy)]
 pub struct SingleThreadId(());
+
 unsafe impl GetThreadId for SingleThreadId {
     const INIT: Self = Self(());
+
     fn nonzero_thread_id(&self) -> NonZero<usize> {
-        NonZero::new(1).unwrap()
+        // Safety: This is constant.
+        unsafe { NonZero::new_unchecked(1) }
     }
 }

crates/common/src/lock/thread_mutex.rs

@@ -121,19 +121,23 @@ impl<R: RawMutex, G: GetThreadId, T: ?Sized> ThreadMutex<R, G, T> {
         }
     }
 }
-// Whether ThreadMutex::try_lock failed because the mutex was already locked on another thread or
-// on the current thread
+
+#[derive(Clone, Copy)]
 pub enum TryLockThreadError {
+    /// Failed to lock because mutex was already locked on another thread.
     Other,
+    /// Failed to lock because mutex was already locked on current thread.
     Current,
 }
 
 struct LockedPlaceholder(&'static str);
+
 impl fmt::Debug for LockedPlaceholder {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.write_str(self.0)
     }
 }
+
 impl<R: RawMutex, G: GetThreadId, T: ?Sized + fmt::Debug> fmt::Debug for ThreadMutex<R, G, T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self.try_lock() {

crates/common/src/str.rs

@@ -449,6 +449,7 @@ pub fn to_ascii(value: &str) -> AsciiString {
     unsafe { AsciiString::from_ascii_unchecked(ascii) }
 }
 
+#[derive(Clone, Copy)]
 pub struct UnicodeEscapeCodepoint(pub CodePoint);
 
 impl fmt::Display for UnicodeEscapeCodepoint {

crates/compiler-core/src/bytecode.rs

@@ -32,7 +32,7 @@ mod oparg;
 
 /// Exception table entry for zero-cost exception handling
 /// Format: (start, size, target, depth<<1|lasti)
-#[derive(Clone, Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub struct ExceptionTableEntry {
     /// Start instruction offset (inclusive)
     pub start: u32,
@@ -47,7 +47,7 @@ pub struct ExceptionTableEntry {
 }
 
 impl ExceptionTableEntry {
-    pub fn new(start: u32, end: u32, target: u32, depth: u16, push_lasti: bool) -> Self {
+    pub const fn new(start: u32, end: u32, target: u32, depth: u16, push_lasti: bool) -> Self {
         Self {
             start,
             end,

crates/compiler-core/src/marshal.rs

@@ -6,7 +6,7 @@ use rustpython_wtf8::Wtf8;
 
 pub const FORMAT_VERSION: u32 = 5;
 
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub enum MarshalError {
     /// Unexpected End Of File
     Eof,
@@ -42,6 +42,7 @@ impl core::error::Error for MarshalError {}
 
 type Result<T, E = MarshalError> = core::result::Result<T, E>;
 
+#[derive(Clone, Copy)]
 #[repr(u8)]
 enum Type {
     // Null = b'0',

crates/compiler-core/src/mode.rs

@@ -22,7 +22,7 @@ impl core::str::FromStr for Mode {
 }
 
 /// Returned when a given mode is not valid.
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct ModeParseError;
 
 impl core::fmt::Display for ModeParseError {

crates/sre_engine/src/constants.rs

@@ -14,9 +14,10 @@
 use bitflags::bitflags;
 
 pub const SRE_MAGIC: usize = 20230612;
-#[derive(num_enum::TryFromPrimitive, Debug, PartialEq, Eq)]
-#[repr(u32)]
+
 #[allow(non_camel_case_types, clippy::upper_case_acronyms)]
+#[derive(num_enum::TryFromPrimitive, Copy, Clone, Debug, PartialEq, Eq)]
+#[repr(u32)]
 pub enum SreOpcode {
     FAILURE = 0,
     SUCCESS = 1,
@@ -63,9 +64,9 @@ pub enum SreOpcode {
     RANGE_UNI_IGNORE = 42,
 }
 
-#[derive(num_enum::TryFromPrimitive, Debug, PartialEq, Eq)]
-#[repr(u32)]
 #[allow(non_camel_case_types, clippy::upper_case_acronyms)]
+#[derive(num_enum::TryFromPrimitive, Clone, Copy, Debug, PartialEq, Eq)]
+#[repr(u32)]
 pub enum SreAtCode {
     BEGINNING = 0,
     BEGINNING_LINE = 1,
@@ -81,9 +82,9 @@ pub enum SreAtCode {
     UNI_NON_BOUNDARY = 11,
 }
 
-#[derive(num_enum::TryFromPrimitive, Debug)]
-#[repr(u32)]
 #[allow(non_camel_case_types, clippy::upper_case_acronyms)]
+#[derive(num_enum::TryFromPrimitive, Clone, Copy, Debug)]
+#[repr(u32)]
 pub enum SreCatCode {
     DIGIT = 0,
     NOT_DIGIT = 1,
@@ -120,6 +121,7 @@ bitflags! {
 }
 
 bitflags! {
+    #[derive(Clone, Copy)]
     pub struct SreInfo: u32 {
         const PREFIX = 1;
         const LITERAL = 2;

crates/vm/src/anystr.rs

@@ -16,13 +16,13 @@ pub struct SplitArgs<T: TryFromObject> {
     maxsplit: isize,
 }
 
-#[derive(FromArgs)]
+#[derive(Clone, Copy, FromArgs)]
 pub struct SplitLinesArgs {
     #[pyarg(any, default = false)]
     pub keepends: bool,
 }
 
-#[derive(FromArgs)]
+#[derive(Clone, Copy, FromArgs)]
 pub struct ExpandTabsArgs {
     #[pyarg(any, default = 8)]
     tabsize: isize,

crates/vm/src/builtins/descriptor.rs

@@ -168,7 +168,7 @@ impl Representable for PyMethodDescriptor {
     }
 }
 
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub enum MemberKind {
     Bool = 14,
     ObjectEx = 16,
@@ -176,11 +176,13 @@ pub enum MemberKind {
 
 pub type MemberSetterFunc = Option<fn(&VirtualMachine, PyObjectRef, PySetterValue) -> PyResult<()>>;
 
+#[derive(Clone, Copy)]
 pub enum MemberGetter {
     Getter(fn(&VirtualMachine, PyObjectRef) -> PyResult),
     Offset(usize),
 }
 
+#[derive(Clone, Copy)]
 pub enum MemberSetter {
     Setter(MemberSetterFunc),
     Offset(usize),

crates/vm/src/builtins/module.rs

@@ -9,7 +9,7 @@ use crate::{
 };
 
 #[pyclass(module = false, name = "module")]
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct PyModuleDef {
     // pub index: usize,
     pub name: &'static PyStrInterned,
@@ -26,7 +26,7 @@ pub type ModuleCreate =
     fn(&VirtualMachine, &PyObject, &'static PyModuleDef) -> PyResult<PyRef<PyModule>>;
 pub type ModuleExec = fn(&VirtualMachine, &Py<PyModule>) -> PyResult<()>;
 
-#[derive(Default)]
+#[derive(Clone, Copy, Default)]
 pub struct PyModuleSlots {
     pub create: Option<ModuleCreate>,
     pub exec: Option<ModuleExec>,
@@ -83,7 +83,7 @@ impl PyModuleDef {
 
 #[allow(clippy::new_without_default)] // avoid Default implementation
 #[pyclass(module = false, name = "module")]
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct PyModule {
     // PyObject *md_dict;
     pub def: Option<&'static PyModuleDef>,

crates/vm/src/builtins/namespace.rs

@@ -14,8 +14,8 @@ use crate::{
 ///
 /// SimpleNamespace(**kwargs)
 #[pyclass(module = "types", name = "SimpleNamespace")]
-#[derive(Debug, Default)]
-pub struct PyNamespace {}
+#[derive(Copy, Clone, Debug, Default)]
+pub struct PyNamespace;
 
 impl PyPayload for PyNamespace {
     #[inline]

crates/vm/src/builtins/object.rs

@@ -18,7 +18,7 @@ use itertools::Itertools;
 /// When called, it accepts no arguments and returns a new featureless
 /// instance that has no instance attributes and cannot be given any.
 #[pyclass(module = false, name = "object")]
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct PyBaseObject;
 
 impl PyPayload for PyBaseObject {

crates/vm/src/builtins/singletons.rs

@@ -9,7 +9,7 @@ use crate::{
 };
 
 #[pyclass(module = false, name = "NoneType")]
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct PyNone;
 
 impl PyPayload for PyNone {
@@ -75,7 +75,7 @@ impl AsNumber for PyNone {
 }
 
 #[pyclass(module = false, name = "NotImplementedType")]
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct PyNotImplemented;
 
 impl PyPayload for PyNotImplemented {

crates/vm/src/builtins/slice.rs

@@ -301,7 +301,7 @@ impl Representable for PySlice {
 }
 
 #[pyclass(module = false, name = "EllipsisType")]
-#[derive(Debug)]
+#[derive(Copy, Clone, Debug)]
 pub struct PyEllipsis;
 
 impl PyPayload for PyEllipsis {

crates/vm/src/builtins/zip.rs

@@ -24,7 +24,7 @@ impl PyPayload for PyZip {
     }
 }
 
-#[derive(FromArgs)]
+#[derive(Clone, Copy, FromArgs)]
 pub struct PyZipNewArgs {
     #[pyarg(named, optional)]
     strict: OptionalArg<bool>,

crates/vm/src/dict_inner.rs

@@ -124,7 +124,7 @@ struct DictEntry<T> {
 }
 static_assertions::assert_eq_size!(DictEntry<PyObjectRef>, Option<DictEntry<PyObjectRef>>);
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub struct DictSize {
     indices_size: usize,
     pub entries_size: usize,

crates/vm/src/function/method.rs

@@ -63,7 +63,7 @@ macro_rules! define_methods {
     };
 }
 
-#[derive(Clone)]
+#[derive(Clone, Copy)]
 pub struct PyMethodDef {
     pub name: &'static str, // TODO: interned
     pub func: &'static dyn PyNativeFn,
@@ -270,7 +270,7 @@ impl core::fmt::Debug for PyMethodDef {
 // This is not a part of CPython API.
 // But useful to support dynamically generated methods
 #[pyclass(name, module = false, ctx = "method_def")]
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct HeapMethodDef {
     method: PyMethodDef,
 }

crates/vm/src/function/number.rs

@@ -14,7 +14,7 @@ use num_traits::PrimInt;
 /// method, this method will first be called to convert the object into a float.
 /// If `__complex__()` is not defined then it falls back to `__float__()`. If
 /// `__float__()` is not defined it falls back to `__index__()`.
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 #[repr(transparent)]
 pub struct ArgIntoComplex {
     value: Complex64,
@@ -52,7 +52,7 @@ impl TryFromObject for ArgIntoComplex {
 /// If the object is not a Python floating point object but has a `__float__()`
 /// method, this method will first be called to convert the object into a float.
 /// If `__float__()` is not defined then it falls back to `__index__()`.
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 #[repr(transparent)]
 pub struct ArgIntoFloat {
     value: f64,
@@ -95,7 +95,7 @@ impl TryFromObject for ArgIntoFloat {
 /// By default an object is considered true unless its class defines either a
 /// `__bool__()` method that returns False or a `__len__()` method that returns
 /// zero, when called with the object.
-#[derive(Debug, Default, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
 pub struct ArgIntoBool {
     value: bool,
 }

crates/vm/src/protocol/buffer.rs

@@ -14,6 +14,7 @@ use alloc::borrow::Cow;
 use core::{fmt::Debug, ops::Range};
 use itertools::Itertools;
 
+#[derive(Clone, Copy)]
 pub struct BufferMethods {
     pub obj_bytes: fn(&PyBuffer) -> BorrowedValue<'_, [u8]>,
     pub obj_bytes_mut: fn(&PyBuffer) -> BorrowedValueMut<'_, [u8]>,

crates/vm/src/protocol/mapping.rs

@@ -48,7 +48,7 @@ impl PyMappingSlots {
 }
 
 #[allow(clippy::type_complexity)]
-#[derive(Default)]
+#[derive(Clone, Copy, Default)]
 pub struct PyMappingMethods {
     pub length: Option<fn(PyMapping<'_>, &VirtualMachine) -> PyResult<usize>>,
     pub subscript: Option<fn(PyMapping<'_>, &PyObject, &VirtualMachine) -> PyResult>,

crates/vm/src/protocol/sequence.rs

@@ -70,7 +70,7 @@ impl PySequenceSlots {
 }
 
 #[allow(clippy::type_complexity)]
-#[derive(Default)]
+#[derive(Clone, Copy, Default)]
 pub struct PySequenceMethods {
     pub length: Option<fn(PySequence<'_>, &VirtualMachine) -> PyResult<usize>>,
     pub concat: Option<fn(PySequence<'_>, &PyObject, &VirtualMachine) -> PyResult>,

crates/vm/src/sliceable.rs

@@ -252,6 +252,7 @@ impl<T: Clone> SliceableSequenceOp for [T] {
     }
 }
 
+#[derive(Clone, Copy)]
 pub enum SequenceIndex {
     Int(isize),
     Slice(SaturatedSlice),
@@ -403,6 +404,7 @@ impl SaturatedSlice {
     }
 }
 
+#[derive(Clone, Copy)]
 pub struct SaturatedSliceIter {
     index: isize,
     step: isize,

crates/vm/src/stdlib/marshal.rs

@@ -25,6 +25,7 @@ mod decl {
     #[pyattr(name = "version")]
     use marshal::FORMAT_VERSION;
 
+    #[derive(Clone, Copy)]
     pub struct DumpError;
 
     impl marshal::Dumpable for PyObjectRef {

crates/vm/src/stdlib/os.rs

@@ -35,7 +35,7 @@ impl crate::convert::IntoPyException for rustix::io::Errno {
 }
 
 #[allow(dead_code)]
-#[derive(FromArgs, Default)]
+#[derive(FromArgs, Default, Copy, Clone)]
 pub struct TargetIsDirectory {
     #[pyarg(any, default = false)]
     pub(crate) target_is_directory: bool,

crates/vm/src/stdlib/typevar.rs

@@ -988,9 +988,9 @@ pub(crate) mod typevar {
 
     #[pyattr]
     #[pyclass(name = "Generic", module = "typing")]
-    #[derive(Debug, PyPayload)]
+    #[derive(Copy, Clone, Debug, PyPayload)]
     #[allow(dead_code)]
-    pub struct Generic {}
+    pub struct Generic;
 
     #[pyclass(flags(BASETYPE))]
     impl Generic {

crates/vm/src/stdlib/typing.rs

@@ -49,7 +49,7 @@ pub(crate) mod decl {
     }
 
     #[pyclass(no_attr, name = "NoDefaultType", module = "typing")]
-    #[derive(Debug, PyPayload)]
+    #[derive(Clone, Copy, Debug, PyPayload)]
     pub struct NoDefault;
 
     #[pyclass(with(Constructor, Representable), flags(BASETYPE))]

crates/wasm/src/vm_class.rs

@@ -102,6 +102,7 @@ pub(crate) fn weak_vm(vm: &VirtualMachine) -> Weak<StoredVirtualMachine> {
     STORED_VMS.with_borrow(|vms| Rc::downgrade(vms.get(id).expect("VirtualMachine is not valid")))
 }
 
+#[derive(Clone, Copy)]
 #[wasm_bindgen(js_name = vmStore)]
 pub struct VMStore;
 

examples/dis.rs

@@ -60,7 +60,7 @@ fn main() -> Result<(), lexopt::Error> {
 
     for script in &scripts {
         if script.exists() && script.is_file() {
-            let res = display_script(script, mode, opts.clone(), expand_code_objects);
+            let res = display_script(script, mode, opts, expand_code_objects);
             if let Err(e) = res {
                 error!("Error while compiling {script:?}: {e}");
             }