feat: implement milestone 2 write operations (#16)

Add support for 10 MongoDB write operations:

Insert:
- insertOne(document, options)
- insertMany(documents, options)

Update:
- updateOne(filter, update, options)
- updateMany(filter, update, options)
- replaceOne(filter, replacement, options)

Delete:
- deleteOne(filter, options)
- deleteMany(filter, options)

Atomic find-and-modify:
- findOneAndUpdate(filter, update, options)
- findOneAndReplace(filter, replacement, options)
- findOneAndDelete(filter, options)

Supported options include:
- writeConcern (w, j; wtimeout parsed but ignored in driver v2)
- upsert, hint, collation, arrayFilters, let
- bypassDocumentValidation, comment, ordered
- sort, projection, returnDocument

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: h3n4l

README.md

@@ -121,20 +121,56 @@ Results are returned in Extended JSON (Relaxed) format:
 | BinData() | `BinData(subtype, base64)` | |
 | RegExp() | `RegExp("pattern", "flags")`, `/pattern/flags` | |
 
-### Milestone 2: Write Operations (Planned)
+### Milestone 2: Write Operations (Current)
+
+#### Insert Commands
+
+| Command | Syntax | Status |
+|---------|--------|--------|
+| db.collection.insertOne() | `insertOne(document, options)` | Supported |
+| db.collection.insertMany() | `insertMany(documents, options)` | Supported |
+
+#### Update Commands
+
+| Command | Syntax | Status |
+|---------|--------|--------|
+| db.collection.updateOne() | `updateOne(filter, update, options)` | Supported |
+| db.collection.updateMany() | `updateMany(filter, update, options)` | Supported |
+| db.collection.replaceOne() | `replaceOne(filter, replacement, options)` | Supported |
+
+#### Delete Commands
+
+| Command | Syntax | Status |
+|---------|--------|--------|
+| db.collection.deleteOne() | `deleteOne(filter, options)` | Supported |
+| db.collection.deleteMany() | `deleteMany(filter, options)` | Supported |
+
+#### Atomic Find-and-Modify Commands
 
 | Command | Syntax | Status |
 |---------|--------|--------|
-| db.collection.insertOne() | `insertOne(document)` | Not yet supported |
-| db.collection.insertMany() | `insertMany(documents)` | Not yet supported |
-| db.collection.updateOne() | `updateOne(filter, update)` | Not yet supported |
-| db.collection.updateMany() | `updateMany(filter, update)` | Not yet supported |
-| db.collection.deleteOne() | `deleteOne(filter)` | Not yet supported |
-| db.collection.deleteMany() | `deleteMany(filter)` | Not yet supported |
-| db.collection.replaceOne() | `replaceOne(filter, replacement)` | Not yet supported |
-| db.collection.findOneAndUpdate() | `findOneAndUpdate(filter, update)` | Not yet supported |
-| db.collection.findOneAndReplace() | `findOneAndReplace(filter, replacement)` | Not yet supported |
-| db.collection.findOneAndDelete() | `findOneAndDelete(filter)` | Not yet supported |
+| db.collection.findOneAndUpdate() | `findOneAndUpdate(filter, update, options)` | Supported |
+| db.collection.findOneAndReplace() | `findOneAndReplace(filter, replacement, options)` | Supported |
+| db.collection.findOneAndDelete() | `findOneAndDelete(filter, options)` | Supported |
+
+#### Write Operation Options
+
+| Option | Applies To | Description |
+|--------|-----------|-------------|
+| `writeConcern` | All write ops | Write concern settings (`w`, `j`, `wtimeout`*) |
+| `bypassDocumentValidation` | Insert, Update, Replace, FindOneAndUpdate/Replace | Skip schema validation |
+| `comment` | All write ops | Comment for server logs |
+| `ordered` | insertMany | Execute inserts sequentially (default: true) |
+| `upsert` | Update, Replace, FindOneAndUpdate/Replace | Insert if no match found |
+| `hint` | Update, Replace, Delete, FindOneAnd* | Force index usage |
+| `collation` | Update, Replace, Delete, FindOneAnd* | String comparison rules |
+| `arrayFilters` | updateOne, updateMany, findOneAndUpdate | Array element filtering |
+| `let` | Update, Replace, Delete, FindOneAnd* | Variables for expressions |
+| `sort` | updateOne, replaceOne, FindOneAnd* | Document selection order |
+| `projection` | FindOneAnd* | Fields to return |
+| `returnDocument` | FindOneAndUpdate/Replace | Return "before" or "after" |
+
+*Note: `wtimeout` is parsed but ignored as it's not supported in MongoDB Go driver v2.
 
 ### Milestone 3: Administrative Operations (Planned)
 

error_test.go

@@ -32,13 +32,13 @@ func TestPlannedOperation(t *testing.T) {
 	gc := gomongo.NewClient(client)
 	ctx := context.Background()
 
-	// insertOne is a planned M2 operation - should return PlannedOperationError
-	_, err := gc.Execute(ctx, dbName, "db.users.insertOne({ name: 'test' })")
+	// createIndex is a planned M3 operation - should return PlannedOperationError
+	_, err := gc.Execute(ctx, dbName, "db.users.createIndex({ name: 1 })")
 	require.Error(t, err)
 
 	var plannedErr *gomongo.PlannedOperationError
 	require.ErrorAs(t, err, &plannedErr)
-	require.Equal(t, "insertOne()", plannedErr.Operation)
+	require.Equal(t, "createIndex()", plannedErr.Operation)
 }
 
 func TestUnsupportedOperation(t *testing.T) {
@@ -78,8 +78,9 @@ func TestUnsupportedOptionError(t *testing.T) {
 func TestMethodRegistryStats(t *testing.T) {
 	total := gomongo.MethodRegistryStats()
 
-	// Registry should contain M2 (10) + M3 (22) = 32 planned methods
-	require.Equal(t, 32, total, "expected 32 planned methods in registry (M2: 10, M3: 22)")
+	// Registry should contain M3 (22) planned methods
+	// M2 write operations have been implemented and removed from the registry
+	require.Equal(t, 22, total, "expected 22 planned methods in registry (M3: 22)")
 
 	// Log stats for visibility
 	t.Logf("Method Registry Stats: total=%d planned methods", total)

internal/executor/executor.go

@@ -40,6 +40,26 @@ func Execute(ctx context.Context, client *mongo.Client, database string, op *tra
 		return executeEstimatedDocumentCount(ctx, client, database, op)
 	case translator.OpDistinct:
 		return executeDistinct(ctx, client, database, op)
+	case translator.OpInsertOne:
+		return executeInsertOne(ctx, client, database, op)
+	case translator.OpInsertMany:
+		return executeInsertMany(ctx, client, database, op)
+	case translator.OpUpdateOne:
+		return executeUpdateOne(ctx, client, database, op)
+	case translator.OpUpdateMany:
+		return executeUpdateMany(ctx, client, database, op)
+	case translator.OpReplaceOne:
+		return executeReplaceOne(ctx, client, database, op)
+	case translator.OpDeleteOne:
+		return executeDeleteOne(ctx, client, database, op)
+	case translator.OpDeleteMany:
+		return executeDeleteMany(ctx, client, database, op)
+	case translator.OpFindOneAndUpdate:
+		return executeFindOneAndUpdate(ctx, client, database, op)
+	case translator.OpFindOneAndReplace:
+		return executeFindOneAndReplace(ctx, client, database, op)
+	case translator.OpFindOneAndDelete:
+		return executeFindOneAndDelete(ctx, client, database, op)
 	default:
 		return nil, fmt.Errorf("unsupported operation: %s", statement)
 	}