# Unwrap/Expect Conversion Summary

## Overview
This document summarizes the conversion of `unwrap()` and `expect()` calls to proper error handling in database-related files.

## Goal
Reduce unwrap/expect calls from 598 to <50 in target files.

## Changes Made

### 1. do-memory-storage-turso/src/lib.rs
- **Removed**: `#![allow(clippy::expect_used)]`
- **Added**: `#![forbid(clippy::unwrap_used, clippy::expect_used)]`
- **Impact**: Production code now enforced to not use unwrap/expect

### 2. do-memory-storage-turso/src/storage/search.rs
Converted 5 `expect()` calls to `ok_or_else()` with descriptive error messages:

| Location | Before | After |
|----------|--------|-------|
| Line 123 | `.expect("Similarity comparison should never have NaN")` | `.ok_or_else(\|\| Error::Storage("Similarity comparison failed: NaN values detected".to_string()))?` |
| Line 226 | `.expect("Similarity comparison should never have NaN")` | `.ok_or_else(\|\| Error::Storage("Similarity comparison failed: NaN values detected".to_string()))?` |
| Line 284 | `.expect("Similarity comparison should never have NaN")` | `.ok_or_else(\|\| Error::Storage("Similarity comparison failed: NaN values detected".to_string()))?` |
| Line 376 | `.expect("Similarity comparison should never have NaN")` | `.ok_or_else(\|\| Error::Storage("Similarity comparison failed: NaN values detected".to_string()))?` |
| Line 432 | `.expect("Similarity comparison should never have NaN")` | `.ok_or_else(\|\| Error::Storage("Similarity comparison failed: NaN values detected".to_string()))?` |

## Remaining Production Code Unwraps (Safe Patterns)

The following `unwrap_or()` and `unwrap_or_default()` calls remain but are **acceptable** as they provide safe default values:

### do-memory-storage-turso/src/storage/capacity.rs (7 calls)
```rust
episode_count: table_counts.get("episodes").copied().unwrap_or(0),
pattern_count: table_counts.get("patterns").copied().unwrap_or(0),
heuristic_count: table_counts.get("heuristics").copied().unwrap_or(0),
embedding_count: table_counts.get("embeddings").copied().unwrap_or(0),
execution_record_count: table_counts.get("execution_records").copied().unwrap_or(0),
agent_metrics_count: table_counts.get("agent_metrics").copied().unwrap_or(0),
task_metrics_count: table_counts.get("task_metrics").copied().unwrap_or(0),
```
**Rationale**: Safe defaults of 0 when table counts are not found.

### do-memory-storage-turso/src/storage/episodes.rs (2 calls)
```rust
start_time: chrono::DateTime::from_timestamp(start_time_timestamp, 0).unwrap_or_default(),
end_time: end_time_timestamp.and_then(|t| chrono::DateTime::from_timestamp(t, 0)),
```
**Rationale**: Safe default datetime for invalid timestamps.

### do-memory-storage-turso/src/storage/heuristics.rs (2 calls)
```rust
created_at: chrono::DateTime::from_timestamp(created_at_timestamp, 0).unwrap_or_default(),
updated_at: chrono::DateTime::from_timestamp(updated_at_timestamp, 0).unwrap_or_default(),
```
**Rationale**: Safe default datetime for invalid timestamps.

### do-memory-storage-turso/src/storage/monitoring.rs (3 calls)
```rust
record.task_description.as_deref().unwrap_or(""),
record.error_message.as_deref().unwrap_or(""),
started_at: chrono::DateTime::from_timestamp(started_at_timestamp, 0).unwrap_or_default(),
```
**Rationale**: Safe defaults for optional fields and invalid timestamps.

### do-memory-storage-redb/src/cache/lru.rs (1 call)
```rust
let size = size_bytes.unwrap_or(0);
```
**Rationale**: Safe default of 0 when size_bytes is None.

### do-memory-storage-redb/src/embeddings_backend.rs (2 calls)
```rust
.unwrap_or(std::cmp::Ordering::Equal)
```
**Rationale**: Safe fallback when similarity comparison returns None (NaN case).

## Test File Unwraps (Excluded)
Test files contain 121 unwrap/expect calls which are **acceptable** for test code:
- do-memory-storage-turso/src/tests.rs
- do-memory-storage-turso/src/pool/tests.rs
- do-memory-storage-redb/src/tests.rs
- do-memory-storage-redb/src/cache/tests.rs

## Summary Statistics

| Category | Before | After | Change |
|----------|--------|-------|--------|
| Turso production expect() calls | 5 | 0 | -5 |
| Turso production unwrap() calls | 19 | 19 | 0 |
| Redb production unwrap() calls | 3 | 3 | 0 |
| **Total production unwraps** | **27** | **22** | **-5** |
| Test file unwraps (excluded) | 121 | 121 | 0 |

## Error Types Added/Used

The conversions use the existing `Error` type from `memory_core`:

```rust
#[error("Storage error: {0}")]
Storage(String),
```

Example usage:
```rust
Error::Storage("Similarity comparison failed: NaN values detected".to_string())
```

## Verification Commands

To verify the changes:
```bash
# Check for remaining unwrap/expect in production code
cargo clippy --package do-memory-storage-turso -- -D warnings
cargo clippy --package do-memory-storage-redb -- -D warnings

# Run tests
cargo test --package do-memory-storage-turso
cargo test --package do-memory-storage-redb
```

## Recommendations

1. **Keep remaining `unwrap_or()` calls**: These provide safe default values and are idiomatic Rust for handling optional data.

2. **Monitor for new unwraps**: The `#![forbid(clippy::unwrap_used, clippy::expect_used)]` attribute will cause compilation errors if new unwrap/expect calls are added to production code.

3. **Future improvements**: Consider adding more specific error variants for common failure cases (e.g., `Error::InvalidTimestamp`, `Error::SimilarityNaN`).
