feat(spectypes): add CIString, LCString, and UCString types with tests

pkg/spectypes/sql_ci_types.go

@@ -0,0 +1,177 @@
+package spectypes
+
+import (
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// CIString is a string that stores, scans, and returns its value exactly as
+// given (no case normalization), but compares case-insensitively via Equal
+// and EqualString. Use it as a bun model field type for columns (e.g.
+// citext, or codes matched case-insensitively) where you want Go-side
+// case-insensitive comparisons without forcing the stored/returned value to
+// a particular case.
+type CIString string
+
+// Value implements driver.Valuer. The value is passed through unchanged.
+func (s CIString) Value() (driver.Value, error) {
+	return string(s), nil
+}
+
+// Scan implements sql.Scanner. The value is stored unchanged.
+func (s *CIString) Scan(value any) error {
+	switch v := value.(type) {
+	case string:
+		*s = CIString(v)
+	case []byte:
+		*s = CIString(v)
+	case nil:
+		*s = ""
+	default:
+		return fmt.Errorf("cannot scan %T into CIString", value)
+	}
+	return nil
+}
+
+// String implements fmt.Stringer.
+func (s CIString) String() string { return string(s) }
+
+// Equal reports whether s and other are equal, ignoring case.
+func (s CIString) Equal(other CIString) bool {
+	return strings.EqualFold(string(s), string(other))
+}
+
+// EqualString reports whether s equals other, ignoring case.
+func (s CIString) EqualString(other string) bool {
+	return strings.EqualFold(string(s), other)
+}
+
+// Compare returns -1, 0, or +1 if s is less than, equal to, or greater than
+// other, ignoring case. Useful with slices.SortFunc or similar.
+func (s CIString) Compare(other CIString) int {
+	return strings.Compare(strings.ToLower(string(s)), strings.ToLower(string(other)))
+}
+
+// Less reports whether s sorts before other, ignoring case. Suitable for
+// sort.Slice or slices.SortFunc comparisons.
+func (s CIString) Less(other CIString) bool {
+	return s.Compare(other) < 0
+}
+
+// LCString is a string that always stores, scans, and returns as lowercase.
+// Use it as a bun model field type for columns that must be normalized to
+// lowercase (e.g. codes, slugs, emails) rather than merely compared
+// case-insensitively; see CIString if the original case must be preserved.
+type LCString string
+
+// Value implements driver.Valuer, always lowercase.
+func (s LCString) Value() (driver.Value, error) {
+	return strings.ToLower(string(s)), nil
+}
+
+// Scan implements sql.Scanner, always lowercase.
+func (s *LCString) Scan(value any) error {
+	switch v := value.(type) {
+	case string:
+		*s = LCString(strings.ToLower(v))
+	case []byte:
+		*s = LCString(strings.ToLower(string(v)))
+	case nil:
+		*s = ""
+	default:
+		return fmt.Errorf("cannot scan %T into LCString", value)
+	}
+	return nil
+}
+
+// String implements fmt.Stringer, always lowercase.
+func (s LCString) String() string { return strings.ToLower(string(s)) }
+
+// Equal reports whether s and other are equal (case-insensitively, since
+// both normalize to lowercase).
+func (s LCString) Equal(other LCString) bool {
+	return s.String() == other.String()
+}
+
+// EqualString reports whether s equals other, ignoring case.
+func (s LCString) EqualString(other string) bool {
+	return s.String() == strings.ToLower(other)
+}
+
+// MarshalJSON implements json.Marshaler, always lowercase. Needed because
+// encoding/json marshals a bare string-kind type as-is and does not call
+// Value/String, so a value constructed directly (not scanned from the DB)
+// would otherwise serialize with its original case.
+func (s LCString) MarshalJSON() ([]byte, error) {
+	return json.Marshal(strings.ToLower(string(s)))
+}
+
+// UnmarshalJSON implements json.Unmarshaler, always lowercase.
+func (s *LCString) UnmarshalJSON(b []byte) error {
+	var str string
+	if err := json.Unmarshal(b, &str); err != nil {
+		return err
+	}
+	*s = LCString(strings.ToLower(str))
+	return nil
+}
+
+// UCString is a string that always stores, scans, and returns as uppercase.
+// Use it as a bun model field type for columns that must be normalized to
+// uppercase (e.g. table prefix codes) rather than merely compared
+// case-insensitively; see CIString if the original case must be preserved.
+type UCString string
+
+// Value implements driver.Valuer, always uppercase.
+func (s UCString) Value() (driver.Value, error) {
+	return strings.ToUpper(string(s)), nil
+}
+
+// Scan implements sql.Scanner, always uppercase.
+func (s *UCString) Scan(value any) error {
+	switch v := value.(type) {
+	case string:
+		*s = UCString(strings.ToUpper(v))
+	case []byte:
+		*s = UCString(strings.ToUpper(string(v)))
+	case nil:
+		*s = ""
+	default:
+		return fmt.Errorf("cannot scan %T into UCString", value)
+	}
+	return nil
+}
+
+// String implements fmt.Stringer, always uppercase.
+func (s UCString) String() string { return strings.ToUpper(string(s)) }
+
+// Equal reports whether s and other are equal (case-insensitively, since
+// both normalize to uppercase).
+func (s UCString) Equal(other UCString) bool {
+	return s.String() == other.String()
+}
+
+// EqualString reports whether s equals other, ignoring case.
+func (s UCString) EqualString(other string) bool {
+	return s.String() == strings.ToUpper(other)
+}
+
+// MarshalJSON implements json.Marshaler, always uppercase. Needed because
+// encoding/json marshals a bare string-kind type as-is and does not call
+// Value/String, so a value constructed directly (not scanned from the DB)
+// would otherwise serialize with its original case.
+func (s UCString) MarshalJSON() ([]byte, error) {
+	return json.Marshal(strings.ToUpper(string(s)))
+}
+
+// UnmarshalJSON implements json.Unmarshaler, always uppercase.
+func (s *UCString) UnmarshalJSON(b []byte) error {
+	var str string
+	if err := json.Unmarshal(b, &str); err != nil {
+		return err
+	}
+	*s = UCString(strings.ToUpper(str))
+	return nil
+}

pkg/spectypes/sql_ci_types_test.go

@@ -0,0 +1,379 @@
+package spectypes
+
+import (
+	"encoding/json"
+	"sort"
+	"testing"
+)
+
+func TestCIString_Scan(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    interface{}
+		expected CIString
+	}{
+		{name: "plain string", input: "MixedCase", expected: "MixedCase"},
+		{name: "bytes as string", input: []byte("FromBytes"), expected: "FromBytes"},
+		{name: "nil value", input: nil, expected: ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var s CIString
+			if err := s.Scan(tt.input); err != nil {
+				t.Fatalf("Scan failed: %v", err)
+			}
+			if s != tt.expected {
+				t.Errorf("expected %q, got %q", tt.expected, s)
+			}
+		})
+	}
+}
+
+func TestCIString_Scan_InvalidType(t *testing.T) {
+	var s CIString
+	if err := s.Scan(123); err == nil {
+		t.Fatal("expected error scanning int into CIString, got nil")
+	}
+}
+
+func TestCIString_Value(t *testing.T) {
+	s := CIString("MixedCase")
+	v, err := s.Value()
+	if err != nil {
+		t.Fatalf("Value failed: %v", err)
+	}
+	if v != "MixedCase" {
+		t.Errorf("expected %q, got %q (case must be preserved)", "MixedCase", v)
+	}
+}
+
+func TestCIString_String(t *testing.T) {
+	s := CIString("MixedCase")
+	if s.String() != "MixedCase" {
+		t.Errorf("expected %q, got %q", "MixedCase", s.String())
+	}
+}
+
+func TestCIString_Equal(t *testing.T) {
+	tests := []struct {
+		name     string
+		a, b     CIString
+		expected bool
+	}{
+		{name: "same case", a: "ABC", b: "ABC", expected: true},
+		{name: "different case", a: "ABC", b: "abc", expected: true},
+		{name: "mixed case", a: "AbC", b: "aBc", expected: true},
+		{name: "not equal", a: "ABC", b: "XYZ", expected: false},
+		{name: "both empty", a: "", b: "", expected: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := tt.a.Equal(tt.b); got != tt.expected {
+				t.Errorf("Equal(%q, %q) = %v, want %v", tt.a, tt.b, got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestCIString_EqualString(t *testing.T) {
+	s := CIString("ABC")
+	if !s.EqualString("abc") {
+		t.Error("expected EqualString to match case-insensitively")
+	}
+	if s.EqualString("xyz") {
+		t.Error("expected EqualString to not match different strings")
+	}
+}
+
+func TestCIString_Compare(t *testing.T) {
+	tests := []struct {
+		name     string
+		a, b     CIString
+		expected int
+	}{
+		{name: "equal same case", a: "abc", b: "abc", expected: 0},
+		{name: "equal different case", a: "ABC", b: "abc", expected: 0},
+		{name: "less", a: "abc", b: "xyz", expected: -1},
+		{name: "less different case", a: "ABC", b: "xyz", expected: -1},
+		{name: "greater", a: "xyz", b: "abc", expected: 1},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := tt.a.Compare(tt.b); got != tt.expected {
+				t.Errorf("Compare(%q, %q) = %v, want %v", tt.a, tt.b, got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestCIString_Less(t *testing.T) {
+	if !CIString("abc").Less("xyz") {
+		t.Error("expected abc < xyz")
+	}
+	if CIString("xyz").Less("abc") {
+		t.Error("expected xyz not < abc")
+	}
+	if CIString("ABC").Less("abc") {
+		t.Error("expected ABC not < abc (equal ignoring case)")
+	}
+}
+
+func TestCIString_Sort(t *testing.T) {
+	vals := []CIString{"banana", "Apple", "cherry", "apple"}
+	sort.Slice(vals, func(i, j int) bool { return vals[i].Less(vals[j]) })
+
+	// After a case-insensitive sort, "Apple"/"apple" must be adjacent and first,
+	// followed by banana then cherry.
+	if !vals[0].EqualString("apple") || !vals[1].EqualString("apple") {
+		t.Errorf("expected the two apple variants first, got %v", vals)
+	}
+	if !vals[2].EqualString("banana") {
+		t.Errorf("expected banana third, got %v", vals)
+	}
+	if !vals[3].EqualString("cherry") {
+		t.Errorf("expected cherry fourth, got %v", vals)
+	}
+}
+
+func TestLCString_Scan(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    interface{}
+		expected LCString
+	}{
+		{name: "mixed case string", input: "MixedCase", expected: "mixedcase"},
+		{name: "bytes mixed case", input: []byte("FromBytes"), expected: "frombytes"},
+		{name: "nil value", input: nil, expected: ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var s LCString
+			if err := s.Scan(tt.input); err != nil {
+				t.Fatalf("Scan failed: %v", err)
+			}
+			if s != tt.expected {
+				t.Errorf("expected %q, got %q", tt.expected, s)
+			}
+		})
+	}
+}
+
+func TestLCString_Scan_InvalidType(t *testing.T) {
+	var s LCString
+	if err := s.Scan(123); err == nil {
+		t.Fatal("expected error scanning int into LCString, got nil")
+	}
+}
+
+func TestLCString_Value(t *testing.T) {
+	s := LCString("MixedCase")
+	v, err := s.Value()
+	if err != nil {
+		t.Fatalf("Value failed: %v", err)
+	}
+	if v != "mixedcase" {
+		t.Errorf("expected %q, got %q", "mixedcase", v)
+	}
+}
+
+func TestLCString_String(t *testing.T) {
+	s := LCString("MixedCase")
+	if s.String() != "mixedcase" {
+		t.Errorf("expected %q, got %q", "mixedcase", s.String())
+	}
+}
+
+func TestLCString_Equal(t *testing.T) {
+	if !LCString("ABC").Equal(LCString("abc")) {
+		t.Error("expected ABC and abc to be equal")
+	}
+	if LCString("ABC").Equal(LCString("xyz")) {
+		t.Error("expected ABC and xyz to not be equal")
+	}
+}
+
+func TestLCString_EqualString(t *testing.T) {
+	if !LCString("ABC").EqualString("abc") {
+		t.Error("expected EqualString to match case-insensitively")
+	}
+}
+
+func TestUCString_Scan(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    interface{}
+		expected UCString
+	}{
+		{name: "mixed case string", input: "MixedCase", expected: "MIXEDCASE"},
+		{name: "bytes mixed case", input: []byte("FromBytes"), expected: "FROMBYTES"},
+		{name: "nil value", input: nil, expected: ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var s UCString
+			if err := s.Scan(tt.input); err != nil {
+				t.Fatalf("Scan failed: %v", err)
+			}
+			if s != tt.expected {
+				t.Errorf("expected %q, got %q", tt.expected, s)
+			}
+		})
+	}
+}
+
+func TestUCString_Scan_InvalidType(t *testing.T) {
+	var s UCString
+	if err := s.Scan(123); err == nil {
+		t.Fatal("expected error scanning int into UCString, got nil")
+	}
+}
+
+func TestUCString_Value(t *testing.T) {
+	s := UCString("MixedCase")
+	v, err := s.Value()
+	if err != nil {
+		t.Fatalf("Value failed: %v", err)
+	}
+	if v != "MIXEDCASE" {
+		t.Errorf("expected %q, got %q", "MIXEDCASE", v)
+	}
+}
+
+func TestUCString_String(t *testing.T) {
+	s := UCString("MixedCase")
+	if s.String() != "MIXEDCASE" {
+		t.Errorf("expected %q, got %q", "MIXEDCASE", s.String())
+	}
+}
+
+func TestUCString_Equal(t *testing.T) {
+	if !UCString("ABC").Equal(UCString("abc")) {
+		t.Error("expected ABC and abc to be equal")
+	}
+	if UCString("ABC").Equal(UCString("xyz")) {
+		t.Error("expected ABC and xyz to not be equal")
+	}
+}
+
+func TestUCString_EqualString(t *testing.T) {
+	if !UCString("ABC").EqualString("abc") {
+		t.Error("expected EqualString to match case-insensitively")
+	}
+}
+
+// TestLCString_MarshalJSON_NotFromDB verifies a value constructed directly
+// in Go (never passed through Scan) still normalizes on JSON marshal.
+func TestLCString_MarshalJSON_NotFromDB(t *testing.T) {
+	s := LCString("MixedCase")
+	b, err := json.Marshal(s)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(b) != `"mixedcase"` {
+		t.Errorf("expected %s, got %s", `"mixedcase"`, b)
+	}
+}
+
+func TestLCString_UnmarshalJSON(t *testing.T) {
+	var s LCString
+	if err := json.Unmarshal([]byte(`"MixedCase"`), &s); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+	if s != "mixedcase" {
+		t.Errorf("expected %q, got %q", "mixedcase", s)
+	}
+}
+
+func TestLCString_JSON_StructField(t *testing.T) {
+	type wrapper struct {
+		Code LCString `json:"code"`
+	}
+	in := wrapper{Code: "MixedCase"}
+	b, err := json.Marshal(in)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(b) != `{"code":"mixedcase"}` {
+		t.Errorf("expected %s, got %s", `{"code":"mixedcase"}`, b)
+	}
+
+	var out wrapper
+	if err := json.Unmarshal([]byte(`{"code":"AnotherMixedCase"}`), &out); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+	if out.Code != "anothermixedcase" {
+		t.Errorf("expected %q, got %q", "anothermixedcase", out.Code)
+	}
+}
+
+// TestUCString_MarshalJSON_NotFromDB verifies a value constructed directly
+// in Go (never passed through Scan) still normalizes on JSON marshal.
+func TestUCString_MarshalJSON_NotFromDB(t *testing.T) {
+	s := UCString("MixedCase")
+	b, err := json.Marshal(s)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(b) != `"MIXEDCASE"` {
+		t.Errorf("expected %s, got %s", `"MIXEDCASE"`, b)
+	}
+}
+
+func TestUCString_UnmarshalJSON(t *testing.T) {
+	var s UCString
+	if err := json.Unmarshal([]byte(`"MixedCase"`), &s); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+	if s != "MIXEDCASE" {
+		t.Errorf("expected %q, got %q", "MIXEDCASE", s)
+	}
+}
+
+func TestUCString_JSON_StructField(t *testing.T) {
+	type wrapper struct {
+		Code UCString `json:"code"`
+	}
+	in := wrapper{Code: "MixedCase"}
+	b, err := json.Marshal(in)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(b) != `{"code":"MIXEDCASE"}` {
+		t.Errorf("expected %s, got %s", `{"code":"MIXEDCASE"}`, b)
+	}
+
+	var out wrapper
+	if err := json.Unmarshal([]byte(`{"code":"AnotherMixedCase"}`), &out); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+	if out.Code != "ANOTHERMIXEDCASE" {
+		t.Errorf("expected %q, got %q", "ANOTHERMIXEDCASE", out.Code)
+	}
+}
+
+// TestCIString_JSON_PreservesCase confirms CIString needs no custom JSON
+// methods: it should never normalize case, only its DB Value/Scan and the
+// Equal/EqualString comparisons apply case-insensitivity.
+func TestCIString_JSON_PreservesCase(t *testing.T) {
+	s := CIString("MixedCase")
+	b, err := json.Marshal(s)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(b) != `"MixedCase"` {
+		t.Errorf("expected %s, got %s", `"MixedCase"`, b)
+	}
+
+	var out CIString
+	if err := json.Unmarshal([]byte(`"AnotherMixedCase"`), &out); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+	if out != "AnotherMixedCase" {
+		t.Errorf("expected case to be preserved, got %q", out)
+	}
+}