icydb_core/value/
storage_key.rs

1//! Module: value::storage_key
2//! Responsibility: fixed-width scalar key encoding for persistent ordering.
3//! Does not own: typed primary-key semantics (`Id<E>`) or query coercion rules.
4//! Boundary: shared by value normalization and data/index persistence layers.
5//!
6//! `StorageKey` is a storage-normalized scalar and MUST NOT be used as a
7//! public primary-key abstraction.
8
9#![expect(clippy::cast_possible_truncation)]
10
11use super::Value;
12use crate::{
13    error::InternalError,
14    traits::Repr,
15    types::{Account, Principal, Subaccount, Timestamp, Ulid},
16};
17use candid::CandidType;
18use derive_more::Display;
19use serde::{Deserialize, Serialize};
20use std::cmp::Ordering;
21use thiserror::Error as ThisError;
22
23///
24/// StorageKeyEncodeError
25/// Errors returned when encoding a storage key for persistence.
26///
27
28#[derive(Debug, ThisError)]
29pub enum StorageKeyEncodeError {
30    #[error("account owner principal exceeds max length: {len} bytes (limit {max})")]
31    AccountOwnerTooLarge { len: usize, max: usize },
32
33    #[error("account payload length mismatch: {len} bytes (expected {expected})")]
34    AccountLengthMismatch { len: usize, expected: usize },
35
36    #[error("value kind '{kind}' is not storage-key encodable")]
37    UnsupportedValueKind { kind: &'static str },
38
39    #[error("principal exceeds max length: {len} bytes (limit {max})")]
40    PrincipalTooLarge { len: usize, max: usize },
41}
42
43impl From<StorageKeyEncodeError> for InternalError {
44    fn from(err: StorageKeyEncodeError) -> Self {
45        Self::serialize_unsupported(err.to_string())
46    }
47}
48
49///
50/// StorageKeyDecodeError
51/// Errors returned when decoding a persisted storage key payload.
52///
53
54#[derive(Debug, ThisError)]
55pub enum StorageKeyDecodeError {
56    #[error("corrupted StorageKey: invalid size")]
57    InvalidSize,
58
59    #[error("corrupted StorageKey: invalid tag")]
60    InvalidTag,
61
62    #[error("corrupted StorageKey: invalid principal length")]
63    InvalidPrincipalLength,
64
65    #[error("corrupted StorageKey: non-zero {field} padding")]
66    NonZeroPadding { field: &'static str },
67
68    #[error("corrupted StorageKey: invalid account payload ({reason})")]
69    InvalidAccountPayload { reason: &'static str },
70}
71
72///
73/// StorageKey
74///
75/// Storage-normalized scalar key used by persistence and indexing.
76///
77/// This type defines the *only* on-disk representation for scalar keys.
78/// It is deliberately separated from typed primary-key values (`Id<E>`).
79///
80
81#[derive(CandidType, Clone, Copy, Debug, Deserialize, Display, Eq, Hash, PartialEq, Serialize)]
82pub enum StorageKey {
83    Account(Account),
84    Int(i64),
85    Principal(Principal),
86    Subaccount(Subaccount),
87    Timestamp(Timestamp),
88    Uint(u64),
89    Ulid(Ulid),
90    Unit,
91}
92
93// Local helper to evaluate storage-key encodability from the scalar registry.
94macro_rules! value_is_storage_key_encodable_from_registry {
95    ( @args $value:expr; @entries $( ($scalar:ident, $family:expr, $value_pat:pat, is_numeric_value = $is_numeric:expr, supports_numeric_coercion = $supports_numeric_coercion:expr, supports_arithmetic = $supports_arithmetic:expr, supports_equality = $supports_equality:expr, supports_ordering = $supports_ordering:expr, is_keyable = $is_keyable:expr, is_storage_key_encodable = $is_storage_key_encodable:expr) ),* $(,)? ) => {
96        match $value {
97            $( $value_pat => $is_storage_key_encodable, )*
98            _ => false,
99        }
100    };
101}
102
103impl StorageKey {
104    // ── Variant tags (DO NOT reorder) ────────────────────────────────
105    pub(crate) const TAG_ACCOUNT: u8 = 0;
106    pub(crate) const TAG_INT: u8 = 1;
107    pub(crate) const TAG_PRINCIPAL: u8 = 2;
108    pub(crate) const TAG_SUBACCOUNT: u8 = 3;
109    pub(crate) const TAG_TIMESTAMP: u8 = 4;
110    pub(crate) const TAG_UINT: u8 = 5;
111    pub(crate) const TAG_ULID: u8 = 6;
112    pub(crate) const TAG_UNIT: u8 = 7;
113
114    /// Fixed serialized size in bytes (protocol invariant).
115    /// DO NOT CHANGE without migration.
116    pub const STORED_SIZE_BYTES: u64 = 64;
117    pub const STORED_SIZE_USIZE: usize = Self::STORED_SIZE_BYTES as usize;
118
119    const TAG_SIZE: usize = 1;
120    pub(crate) const TAG_OFFSET: usize = 0;
121
122    pub(crate) const PAYLOAD_OFFSET: usize = Self::TAG_SIZE;
123    const PAYLOAD_SIZE: usize = Self::STORED_SIZE_USIZE - Self::TAG_SIZE;
124
125    pub(crate) const INT_SIZE: usize = 8;
126    pub(crate) const UINT_SIZE: usize = 8;
127    pub(crate) const TIMESTAMP_SIZE: usize = 8;
128    pub(crate) const ULID_SIZE: usize = 16;
129    pub(crate) const SUBACCOUNT_SIZE: usize = 32;
130    const ACCOUNT_MAX_SIZE: usize = 62;
131
132    pub const fn try_from_value(value: &Value) -> Result<Self, StorageKeyEncodeError> {
133        // Storage encodability is a persistent compatibility contract.
134        // Changing admission is a breaking change and may require index migration.
135        // This is intentionally distinct from schema keyability.
136        let is_storage_key_encodable =
137            scalar_registry!(value_is_storage_key_encodable_from_registry, value);
138        if !is_storage_key_encodable {
139            return Err(StorageKeyEncodeError::UnsupportedValueKind {
140                kind: Self::value_kind_label(value),
141            });
142        }
143
144        match value {
145            Value::Account(v) => Ok(Self::Account(*v)),
146            Value::Int(v) => Ok(Self::Int(*v)),
147            Value::Principal(v) => Ok(Self::Principal(*v)),
148            Value::Subaccount(v) => Ok(Self::Subaccount(*v)),
149            Value::Timestamp(v) => Ok(Self::Timestamp(*v)),
150            Value::Uint(v) => Ok(Self::Uint(*v)),
151            Value::Ulid(v) => Ok(Self::Ulid(*v)),
152            Value::Unit => Ok(Self::Unit),
153
154            _ => Err(StorageKeyEncodeError::UnsupportedValueKind {
155                kind: Self::value_kind_label(value),
156            }),
157        }
158    }
159
160    const fn value_kind_label(value: &Value) -> &'static str {
161        match value {
162            Value::Account(_) => "Account",
163            Value::Blob(_) => "Blob",
164            Value::Bool(_) => "Bool",
165            Value::Date(_) => "Date",
166            Value::Decimal(_) => "Decimal",
167            Value::Duration(_) => "Duration",
168            Value::Enum(_) => "Enum",
169            Value::Float32(_) => "Float32",
170            Value::Float64(_) => "Float64",
171            Value::Int(_) => "Int",
172            Value::Int128(_) => "Int128",
173            Value::IntBig(_) => "IntBig",
174            Value::List(_) => "List",
175            Value::Map(_) => "Map",
176            Value::Null => "Null",
177            Value::Principal(_) => "Principal",
178            Value::Subaccount(_) => "Subaccount",
179            Value::Text(_) => "Text",
180            Value::Timestamp(_) => "Timestamp",
181            Value::Uint(_) => "Uint",
182            Value::Uint128(_) => "Uint128",
183            Value::UintBig(_) => "UintBig",
184            Value::Ulid(_) => "Ulid",
185            Value::Unit => "Unit",
186        }
187    }
188
189    const fn tag(&self) -> u8 {
190        match self {
191            Self::Account(_) => Self::TAG_ACCOUNT,
192            Self::Int(_) => Self::TAG_INT,
193            Self::Principal(_) => Self::TAG_PRINCIPAL,
194            Self::Subaccount(_) => Self::TAG_SUBACCOUNT,
195            Self::Timestamp(_) => Self::TAG_TIMESTAMP,
196            Self::Uint(_) => Self::TAG_UINT,
197            Self::Ulid(_) => Self::TAG_ULID,
198            Self::Unit => Self::TAG_UNIT,
199        }
200    }
201
202    /// Sentinel key representing the maximum storable value.
203    #[must_use]
204    pub fn max_storable() -> Self {
205        Self::Account(Account::max_storable())
206    }
207
208    /// Global minimum key for scan bounds.
209    pub const MIN: Self = Self::Account(Account::from_parts(Principal::from_slice(&[]), None));
210
211    #[must_use]
212    pub const fn lower_bound() -> Self {
213        Self::MIN
214    }
215
216    #[must_use]
217    pub const fn upper_bound() -> Self {
218        Self::Unit
219    }
220
221    const fn variant_rank(&self) -> u8 {
222        self.tag()
223    }
224
225    const fn from_account_encode_error(
226        err: crate::types::AccountEncodeError,
227    ) -> StorageKeyEncodeError {
228        match err {
229            crate::types::AccountEncodeError::OwnerEncode(inner) => {
230                Self::from_principal_encode_error(inner)
231            }
232            crate::types::AccountEncodeError::OwnerTooLarge { len, max } => {
233                StorageKeyEncodeError::AccountOwnerTooLarge { len, max }
234            }
235        }
236    }
237
238    const fn from_principal_encode_error(
239        err: crate::types::PrincipalEncodeError,
240    ) -> StorageKeyEncodeError {
241        match err {
242            crate::types::PrincipalEncodeError::TooLarge { len, max } => {
243                StorageKeyEncodeError::PrincipalTooLarge { len, max }
244            }
245        }
246    }
247
248    /// Encode this key into its fixed-size on-disk representation.
249    pub fn to_bytes(self) -> Result<[u8; Self::STORED_SIZE_USIZE], StorageKeyEncodeError> {
250        // Phase 1: write variant tag and select fixed payload window.
251        let mut buf = [0u8; Self::STORED_SIZE_USIZE];
252        buf[Self::TAG_OFFSET] = self.tag();
253        let payload = &mut buf[Self::PAYLOAD_OFFSET..=Self::PAYLOAD_SIZE];
254
255        // Phase 2: encode variant payload into the normalized fixed-width frame.
256        match self {
257            Self::Account(v) => {
258                let bytes = v.to_bytes().map_err(Self::from_account_encode_error)?;
259                if bytes.len() != Self::ACCOUNT_MAX_SIZE {
260                    return Err(StorageKeyEncodeError::AccountLengthMismatch {
261                        len: bytes.len(),
262                        expected: Self::ACCOUNT_MAX_SIZE,
263                    });
264                }
265                payload[..bytes.len()].copy_from_slice(&bytes);
266            }
267            Self::Int(v) => {
268                let biased = v.cast_unsigned() ^ (1u64 << 63);
269                payload[..Self::INT_SIZE].copy_from_slice(&biased.to_be_bytes());
270            }
271            Self::Uint(v) => payload[..Self::UINT_SIZE].copy_from_slice(&v.to_be_bytes()),
272            Self::Timestamp(v) => {
273                payload[..Self::TIMESTAMP_SIZE].copy_from_slice(&v.repr().to_be_bytes());
274            }
275            Self::Principal(v) => {
276                let bytes = v.to_bytes().map_err(Self::from_principal_encode_error)?;
277                let len = bytes.len();
278                payload[0] =
279                    u8::try_from(len).map_err(|_| StorageKeyEncodeError::PrincipalTooLarge {
280                        len,
281                        max: Principal::MAX_LENGTH_IN_BYTES as usize,
282                    })?;
283                payload[1..=len].copy_from_slice(&bytes[..len]);
284            }
285            Self::Subaccount(v) => payload[..Self::SUBACCOUNT_SIZE].copy_from_slice(&v.to_array()),
286            Self::Ulid(v) => payload[..Self::ULID_SIZE].copy_from_slice(&v.to_bytes()),
287            Self::Unit => {}
288        }
289
290        Ok(buf)
291    }
292
293    pub fn try_from_bytes(bytes: &[u8]) -> Result<Self, StorageKeyDecodeError> {
294        // Phase 1: enforce frame size before reading tag/payload.
295        if bytes.len() != Self::STORED_SIZE_USIZE {
296            return Err(StorageKeyDecodeError::InvalidSize);
297        }
298
299        let tag = bytes[Self::TAG_OFFSET];
300        let payload = &bytes[Self::PAYLOAD_OFFSET..=Self::PAYLOAD_SIZE];
301
302        let ensure_zero_padding = |used: usize, ctx: &'static str| {
303            if payload[used..].iter().all(|&b| b == 0) {
304                Ok(())
305            } else {
306                Err(StorageKeyDecodeError::NonZeroPadding { field: ctx })
307            }
308        };
309
310        // Phase 2: decode tagged payload and enforce zero-padding invariants.
311        match tag {
312            Self::TAG_ACCOUNT => {
313                let end = Account::STORED_SIZE as usize;
314                ensure_zero_padding(end, "account")?;
315                Ok(Self::Account(
316                    Account::try_from_bytes(&payload[..end]).map_err(|reason| {
317                        StorageKeyDecodeError::InvalidAccountPayload { reason }
318                    })?,
319                ))
320            }
321            Self::TAG_INT => {
322                let mut buf = [0u8; Self::INT_SIZE];
323                buf.copy_from_slice(&payload[..Self::INT_SIZE]);
324                ensure_zero_padding(Self::INT_SIZE, "int")?;
325                Ok(Self::Int(
326                    (u64::from_be_bytes(buf) ^ (1u64 << 63)).cast_signed(),
327                ))
328            }
329            Self::TAG_PRINCIPAL => {
330                let len = payload[0] as usize;
331                if len > Principal::MAX_LENGTH_IN_BYTES as usize {
332                    return Err(StorageKeyDecodeError::InvalidPrincipalLength);
333                }
334                ensure_zero_padding(1 + len, "principal")?;
335                Ok(Self::Principal(Principal::from_slice(&payload[1..=len])))
336            }
337            Self::TAG_SUBACCOUNT => {
338                ensure_zero_padding(Self::SUBACCOUNT_SIZE, "subaccount")?;
339                let mut buf = [0u8; Self::SUBACCOUNT_SIZE];
340                buf.copy_from_slice(&payload[..Self::SUBACCOUNT_SIZE]);
341                Ok(Self::Subaccount(Subaccount::from_array(buf)))
342            }
343            Self::TAG_TIMESTAMP => {
344                ensure_zero_padding(Self::TIMESTAMP_SIZE, "timestamp")?;
345                let mut buf = [0u8; Self::TIMESTAMP_SIZE];
346                buf.copy_from_slice(&payload[..Self::TIMESTAMP_SIZE]);
347                Ok(Self::Timestamp(Timestamp::from_repr(i64::from_be_bytes(
348                    buf,
349                ))))
350            }
351            Self::TAG_UINT => {
352                ensure_zero_padding(Self::UINT_SIZE, "uint")?;
353                let mut buf = [0u8; Self::UINT_SIZE];
354                buf.copy_from_slice(&payload[..Self::UINT_SIZE]);
355                Ok(Self::Uint(u64::from_be_bytes(buf)))
356            }
357            Self::TAG_ULID => {
358                ensure_zero_padding(Self::ULID_SIZE, "ulid")?;
359                let mut buf = [0u8; Self::ULID_SIZE];
360                buf.copy_from_slice(&payload[..Self::ULID_SIZE]);
361                Ok(Self::Ulid(Ulid::from_bytes(buf)))
362            }
363            Self::TAG_UNIT => {
364                ensure_zero_padding(0, "unit")?;
365                Ok(Self::Unit)
366            }
367            _ => Err(StorageKeyDecodeError::InvalidTag),
368        }
369    }
370
371    /// Convert this storage-normalized key into a semantic Value.
372    ///
373    /// Intended ONLY for diagnostics, explain output, planner invariants,
374    /// and fingerprinting. Must not be used for query semantics.
375    #[must_use]
376    pub const fn as_value(&self) -> Value {
377        match self {
378            Self::Account(v) => Value::Account(*v),
379            Self::Int(v) => Value::Int(*v),
380            Self::Principal(v) => Value::Principal(*v),
381            Self::Subaccount(v) => Value::Subaccount(*v),
382            Self::Timestamp(v) => Value::Timestamp(*v),
383            Self::Uint(v) => Value::Uint(*v),
384            Self::Ulid(v) => Value::Ulid(*v),
385            Self::Unit => Value::Unit,
386        }
387    }
388}
389
390impl Ord for StorageKey {
391    fn cmp(&self, other: &Self) -> Ordering {
392        match (self, other) {
393            (Self::Account(a), Self::Account(b)) => a.cmp(b),
394            (Self::Int(a), Self::Int(b)) => a.cmp(b),
395            (Self::Principal(a), Self::Principal(b)) => a.cmp(b),
396            (Self::Uint(a), Self::Uint(b)) => a.cmp(b),
397            (Self::Ulid(a), Self::Ulid(b)) => a.cmp(b),
398            (Self::Subaccount(a), Self::Subaccount(b)) => a.cmp(b),
399            (Self::Timestamp(a), Self::Timestamp(b)) => a.cmp(b),
400            _ => self.variant_rank().cmp(&other.variant_rank()),
401        }
402    }
403}
404
405impl PartialOrd for StorageKey {
406    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
407        Some(self.cmp(other))
408    }
409}
410
411impl TryFrom<&[u8]> for StorageKey {
412    type Error = StorageKeyDecodeError;
413    fn try_from(bytes: &[u8]) -> Result<Self, Self::Error> {
414        Self::try_from_bytes(bytes)
415    }
416}
417
418///
419/// TESTS
420///
421
422#[cfg(test)]
423mod tests {
424    use super::{StorageKey, StorageKeyDecodeError, StorageKeyEncodeError};
425    use crate::{
426        types::{
427            Account, Date, Decimal, Duration, Float32, Float64, Int, Int128, Nat, Nat128,
428            Principal, Subaccount, Timestamp, Ulid,
429        },
430        value::{Value, ValueEnum},
431    };
432
433    macro_rules! sample_value_for_scalar {
434        (Account) => {
435            Value::Account(Account::dummy(7))
436        };
437        (Blob) => {
438            Value::Blob(vec![1u8, 2u8, 3u8])
439        };
440        (Bool) => {
441            Value::Bool(true)
442        };
443        (Date) => {
444            Value::Date(Date::new(2024, 1, 2))
445        };
446        (Decimal) => {
447            Value::Decimal(Decimal::new(123, 2))
448        };
449        (Duration) => {
450            Value::Duration(Duration::from_secs(1))
451        };
452        (Enum) => {
453            Value::Enum(ValueEnum::loose("example"))
454        };
455        (Float32) => {
456            Value::Float32(Float32::try_new(1.25).expect("Float32 sample should be finite"))
457        };
458        (Float64) => {
459            Value::Float64(Float64::try_new(2.5).expect("Float64 sample should be finite"))
460        };
461        (Int) => {
462            Value::Int(-7)
463        };
464        (Int128) => {
465            Value::Int128(Int128::from(123i128))
466        };
467        (IntBig) => {
468            Value::IntBig(Int::from(99i32))
469        };
470        (Principal) => {
471            Value::Principal(Principal::from_slice(&[1u8, 2u8, 3u8]))
472        };
473        (Subaccount) => {
474            Value::Subaccount(Subaccount::new([1u8; 32]))
475        };
476        (Text) => {
477            Value::Text("example".to_string())
478        };
479        (Timestamp) => {
480            Value::Timestamp(Timestamp::from_secs(1))
481        };
482        (Uint) => {
483            Value::Uint(7)
484        };
485        (Uint128) => {
486            Value::Uint128(Nat128::from(9u128))
487        };
488        (UintBig) => {
489            Value::UintBig(Nat::from(11u64))
490        };
491        (Ulid) => {
492            Value::Ulid(Ulid::from_u128(42))
493        };
494        (Unit) => {
495            Value::Unit
496        };
497    }
498
499    fn registry_storage_encodable_cases() -> Vec<(Value, bool)> {
500        macro_rules! collect_cases {
501            ( @entries $( ($scalar:ident, $family:expr, $value_pat:pat, is_numeric_value = $is_numeric:expr, supports_numeric_coercion = $supports_numeric_coercion:expr, supports_arithmetic = $supports_arithmetic:expr, supports_equality = $supports_equality:expr, supports_ordering = $supports_ordering:expr, is_keyable = $is_keyable:expr, is_storage_key_encodable = $is_storage_key_encodable:expr) ),* $(,)? ) => {
502                vec![ $( (sample_value_for_scalar!($scalar), $is_storage_key_encodable) ),* ]
503            };
504            ( @args $($ignore:tt)*; @entries $( ($scalar:ident, $family:expr, $value_pat:pat, is_numeric_value = $is_numeric:expr, supports_numeric_coercion = $supports_numeric_coercion:expr, supports_arithmetic = $supports_arithmetic:expr, supports_equality = $supports_equality:expr, supports_ordering = $supports_ordering:expr, is_keyable = $is_keyable:expr, is_storage_key_encodable = $is_storage_key_encodable:expr) ),* $(,)? ) => {
505                vec![ $( (sample_value_for_scalar!($scalar), $is_storage_key_encodable) ),* ]
506            };
507        }
508
509        scalar_registry!(collect_cases)
510    }
511
512    #[test]
513    fn storage_key_try_from_value_matches_registry_flag() {
514        for (value, expected_encodable) in registry_storage_encodable_cases() {
515            assert_eq!(
516                StorageKey::try_from_value(&value).is_ok(),
517                expected_encodable,
518                "value: {value:?}"
519            );
520        }
521    }
522
523    #[test]
524    fn storage_key_known_encodability_contracts() {
525        assert!(StorageKey::try_from_value(&Value::Unit).is_ok());
526        assert!(StorageKey::try_from_value(&Value::Decimal(Decimal::new(1, 0))).is_err());
527        assert!(StorageKey::try_from_value(&Value::Text("x".to_string())).is_err());
528        assert!(StorageKey::try_from_value(&Value::Account(Account::dummy(1))).is_ok());
529    }
530
531    #[test]
532    fn storage_key_unsupported_values_report_kind() {
533        let decimal_err = StorageKey::try_from_value(&Value::Decimal(Decimal::new(1, 0)))
534            .expect_err("Decimal is not storage-key encodable");
535        assert!(matches!(
536            decimal_err,
537            StorageKeyEncodeError::UnsupportedValueKind { kind } if kind == "Decimal"
538        ));
539
540        let text_err = StorageKey::try_from_value(&Value::Text("x".to_string()))
541            .expect_err("Text is not storage-key encodable");
542        assert!(matches!(
543            text_err,
544            StorageKeyEncodeError::UnsupportedValueKind { kind } if kind == "Text"
545        ));
546    }
547
548    #[test]
549    fn storage_keys_sort_deterministically_across_mixed_variants() {
550        let mut keys = vec![
551            StorageKey::try_from_value(&Value::Unit).expect("Unit is encodable"),
552            StorageKey::try_from_value(&Value::Ulid(Ulid::from_u128(2)))
553                .expect("Ulid is encodable"),
554            StorageKey::try_from_value(&Value::Uint(2)).expect("Uint is encodable"),
555            StorageKey::try_from_value(&Value::Timestamp(Timestamp::from_secs(2)))
556                .expect("Timestamp is encodable"),
557            StorageKey::try_from_value(&Value::Subaccount(Subaccount::new([3u8; 32])))
558                .expect("Subaccount is encodable"),
559            StorageKey::try_from_value(&Value::Principal(Principal::from_slice(&[9u8])))
560                .expect("Principal is encodable"),
561            StorageKey::try_from_value(&Value::Int(-1)).expect("Int is encodable"),
562            StorageKey::try_from_value(&Value::Account(Account::dummy(3)))
563                .expect("Account is encodable"),
564        ];
565
566        keys.sort();
567
568        let expected = vec![
569            StorageKey::Account(Account::dummy(3)),
570            StorageKey::Int(-1),
571            StorageKey::Principal(Principal::from_slice(&[9u8])),
572            StorageKey::Subaccount(Subaccount::new([3u8; 32])),
573            StorageKey::Timestamp(Timestamp::from_secs(2)),
574            StorageKey::Uint(2),
575            StorageKey::Ulid(Ulid::from_u128(2)),
576            StorageKey::Unit,
577        ];
578
579        assert_eq!(keys, expected);
580    }
581
582    #[test]
583    fn storage_key_decode_rejects_invalid_size_as_structured_error() {
584        let err =
585            StorageKey::try_from_bytes(&[]).expect_err("decode should reject invalid key size");
586        assert!(matches!(err, StorageKeyDecodeError::InvalidSize));
587    }
588
589    #[test]
590    fn storage_key_decode_rejects_invalid_tag_as_structured_error() {
591        let mut bytes = [0u8; StorageKey::STORED_SIZE_USIZE];
592        bytes[StorageKey::TAG_OFFSET] = 0xFF;
593
594        let err = StorageKey::try_from_bytes(&bytes).expect_err("decode should reject invalid tag");
595        assert!(matches!(err, StorageKeyDecodeError::InvalidTag));
596    }
597
598    #[test]
599    fn storage_key_decode_rejects_non_zero_padding_with_segment_context() {
600        let mut bytes = [0u8; StorageKey::STORED_SIZE_USIZE];
601        bytes[StorageKey::TAG_OFFSET] = StorageKey::TAG_UNIT;
602        bytes[StorageKey::PAYLOAD_OFFSET] = 1;
603
604        let err = StorageKey::try_from_bytes(&bytes)
605            .expect_err("decode should reject non-zero padding for unit payload");
606        assert!(matches!(
607            err,
608            StorageKeyDecodeError::NonZeroPadding { field } if field == "unit"
609        ));
610    }
611}
icydb_core/value/storage_key.rs

icydb_core/value/
storage_key.rs
