Refactored methods into pure functions.

filters/filter.go

@@ -29,7 +29,7 @@ type Filter struct {
 
 // MarshalJSON converts the filter to JSON with standard fields, tag filters
 // (prefixed with "#"), and extensions merged into a single object.
-func (f *Filter) MarshalJSON() ([]byte, error) {
+func MarshalJSON(f Filter) ([]byte, error) {
 	outputMap := make(map[string]interface{})
 
 	// Add standard fields
@@ -86,7 +86,7 @@ func (f *Filter) MarshalJSON() ([]byte, error) {
 
 // UnmarshalJSON parses JSON into the filter, separating standard fields,
 // tag filters (keys starting with "#"), and extensions.
-func (f *Filter) UnmarshalJSON(data []byte) error {
+func UnmarshalJSON(data []byte, f *Filter) error {
 	// Decode into raw map
 	raw := make(FilterExtensions)
 	if err := json.Unmarshal(data, &raw); err != nil {
@@ -182,7 +182,7 @@ func (f *Filter) UnmarshalJSON(data []byte) error {
 // Matches returns true if the event satisfies all filter conditions.
 // Supports prefix matching for IDs and authors, and tag filtering.
 // Does not account for custom extensions.
-func (f *Filter) Matches(event *events.Event) bool {
+func Matches(f Filter, event events.Event) bool {
 	// Check ID
 	if len(f.IDs) > 0 {
 		if !matchesPrefix(event.ID, f.IDs) {

filters/filter_json_test.go

@@ -584,7 +584,7 @@ var roundTripTestCases = []FilterRoundTripTestCase{
 func TestFilterMarshalJSON(t *testing.T) {
 	for _, tc := range marshalTestCases {
 		t.Run(tc.name, func(t *testing.T) {
-			result, err := tc.filter.MarshalJSON()
+			result, err := MarshalJSON(tc.filter)
 			assert.NoError(t, err)
 
 			var expectedMap, actualMap map[string]interface{}
@@ -602,7 +602,7 @@ func TestFilterUnmarshalJSON(t *testing.T) {
 	for _, tc := range unmarshalTestCases {
 		t.Run(tc.name, func(t *testing.T) {
 			var result Filter
-			err := result.UnmarshalJSON([]byte(tc.input))
+			err := UnmarshalJSON([]byte(tc.input), &result)
 			assert.NoError(t, err)
 
 			expectEqualFilters(t, result, tc.expected)
@@ -613,11 +613,11 @@ func TestFilterUnmarshalJSON(t *testing.T) {
 func TestFilterRoundTrip(t *testing.T) {
 	for _, tc := range roundTripTestCases {
 		t.Run(tc.name, func(t *testing.T) {
-			jsonBytes, err := tc.filter.MarshalJSON()
+			jsonBytes, err := MarshalJSON(tc.filter)
 			assert.NoError(t, err)
 
 			var result Filter
-			err = result.UnmarshalJSON(jsonBytes)
+			err = UnmarshalJSON(jsonBytes, &result)
 			assert.NoError(t, err)
 
 			expectEqualFilters(t, result, tc.filter)

filters/filter_match_test.go

@@ -391,7 +391,7 @@ func TestEventFilterMatching(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			actualIDs := []string{}
 			for _, event := range testEvents {
-				if tc.filter.Matches(&event) {
+				if Matches(tc.filter, event) {
 					actualIDs = append(actualIDs, event.ID[:8])
 				}
 			}
@@ -416,5 +416,5 @@ func TestEventFilterMatchingSkipMalformedTags(t *testing.T) {
 		},
 	}
 
-	assert.True(t, filter.Matches(&event))
+	assert.True(t, Matches(filter, event))
 }