Fixed panics with Parse methods - resolves #29

Co-authored-by: sonnemusk <sonnemusk@gmail.com>

Author: ankane

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.4.1 (unreleased)
+
+- Fixed panics with `Parse` methods
+
 ## 0.4.0 (2026-05-18)
 
 - Changed `ent` and `pgx` packages to modules

halfvec.go

@@ -35,6 +35,15 @@ func (v HalfVector) String() string {
 
 // Parse parses a string representation of a half vector.
 func (v *HalfVector) Parse(s string) error {
+	if len(s) < 2 {
+		return fmt.Errorf("malformed halfvec literal")
+	}
+
+	if len(s) == 2 {
+		v.vec = []float32{}
+		return nil
+	}
+
 	sp := strings.Split(s[1:len(s)-1], ",")
 	v.vec = make([]float32, 0, len(sp))
 	for i := 0; i < len(sp); i++ {

sparsevec.go

@@ -95,19 +95,33 @@ func (v SparseVector) String() string {
 // Parse parses a string representation of a sparse vector.
 func (v *SparseVector) Parse(s string) error {
 	sp := strings.SplitN(s, "/", 2)
+	if len(sp) != 2 {
+		return fmt.Errorf("malformed sparsevec literal")
+	}
 
 	dim, err := strconv.ParseInt(sp[1], 10, 32)
 	if err != nil {
 		return err
 	}
 
-	elements := strings.Split(sp[0][1:len(sp[0])-1], ",")
+	if len(sp[0]) < 2 {
+		return fmt.Errorf("malformed sparsevec literal")
+	}
+
+	elements := []string{}
+	if len(sp[0]) > 2 {
+		elements = strings.Split(sp[0][1:len(sp[0])-1], ",")
+	}
+
 	v.dim = int32(dim)
 	v.indices = make([]int32, 0, len(elements))
 	v.values = make([]float32, 0, len(elements))
 
 	for i := 0; i < len(elements); i++ {
 		ep := strings.SplitN(elements[i], ":", 2)
+		if len(ep) != 2 {
+			return fmt.Errorf("malformed sparsevec literal")
+		}
 
 		n, err := strconv.ParseInt(ep[0], 10, 32)
 		if err != nil {

test/halfvec_test.go

@@ -32,6 +32,19 @@ func TestHalfVectorParse(t *testing.T) {
 	if !reflect.DeepEqual(vec.Slice(), []float32{1, 2, 3}) {
 		t.Error()
 	}
+
+	err = vec.Parse("[]")
+	if err != nil {
+		panic(err)
+	}
+	if !reflect.DeepEqual(vec.Slice(), []float32{}) {
+		t.Error()
+	}
+
+	err = vec.Parse("")
+	if err == nil || err.Error() != "malformed halfvec literal" {
+		t.Error()
+	}
 }
 
 func TestHalfVectorMarshal(t *testing.T) {

test/sparsevec_test.go

@@ -73,4 +73,27 @@ func TestSparseVectorParse(t *testing.T) {
 	if !reflect.DeepEqual(vec.Slice(), []float32{1, 0, 2, 0, 3, 0}) {
 		t.Error()
 	}
+
+	err = vec.Parse("{}/0")
+	if err != nil {
+		panic(err)
+	}
+	if !reflect.DeepEqual(vec.Slice(), []float32{}) {
+		t.Error()
+	}
+
+	err = vec.Parse("")
+	if err == nil || err.Error() != "malformed sparsevec literal" {
+		t.Error()
+	}
+
+	err = vec.Parse("/6")
+	if err == nil || err.Error() != "malformed sparsevec literal" {
+		t.Error()
+	}
+
+	err = vec.Parse("{1}/6")
+	if err == nil || err.Error() != "malformed sparsevec literal" {
+		t.Error()
+	}
 }

test/vector_test.go

@@ -32,6 +32,19 @@ func TestVectorParse(t *testing.T) {
 	if !reflect.DeepEqual(vec.Slice(), []float32{1, 2, 3}) {
 		t.Error()
 	}
+
+	err = vec.Parse("[]")
+	if err != nil {
+		panic(err)
+	}
+	if !reflect.DeepEqual(vec.Slice(), []float32{}) {
+		t.Error()
+	}
+
+	err = vec.Parse("")
+	if err == nil || err.Error() != "malformed vector literal" {
+		t.Error()
+	}
 }
 
 func TestVectorMarshal(t *testing.T) {

vector.go

@@ -45,6 +45,15 @@ func (v Vector) String() string {
 
 // Parse parses a string representation of a vector.
 func (v *Vector) Parse(s string) error {
+	if len(s) < 2 {
+		return fmt.Errorf("malformed vector literal")
+	}
+
+	if len(s) == 2 {
+		v.vec = []float32{}
+		return nil
+	}
+
 	sp := strings.Split(s[1:len(s)-1], ",")
 	v.vec = make([]float32, 0, len(sp))
 	for i := 0; i < len(sp); i++ {