Add validator lib

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/validator/validator_numeric_test.go

@@ -0,0 +1,95 @@
+// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package validator
+
+import (
+	"testing"
+
+	"go.gearno.de/x/ref"
+)
+
+func TestMin(t *testing.T) {
+	tests := []struct {
+		name      string
+		value     any
+		min       int
+		wantError bool
+	}{
+		{"valid int", 10, 5, false},
+		{"exact min", 5, 5, false},
+		{"below min", 3, 5, true},
+		{"valid int pointer", ref.Ref(10), 5, false},
+		{"nil pointer", (*int)(nil), 5, false}, // Skip validation
+		{"non-numeric", "test", 5, true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := Min(tt.min)(tt.value)
+			if (err != nil) != tt.wantError {
+				t.Errorf("Min() error = %v, wantError %v", err, tt.wantError)
+			}
+		})
+	}
+}
+
+func TestMax(t *testing.T) {
+	tests := []struct {
+		name      string
+		value     any
+		max       int
+		wantError bool
+	}{
+		{"valid int", 5, 10, false},
+		{"exact max", 10, 10, false},
+		{"above max", 15, 10, true},
+		{"valid int pointer", ref.Ref(5), 10, false},
+		{"nil pointer", (*int)(nil), 10, false}, // Skip validation
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := Max(tt.max)(tt.value)
+			if (err != nil) != tt.wantError {
+				t.Errorf("Max() error = %v, wantError %v", err, tt.wantError)
+			}
+		})
+	}
+}
+
+func TestRange(t *testing.T) {
+	tests := []struct {
+		name      string
+		value     any
+		min       int
+		max       int
+		wantError bool
+	}{
+		{"in range", 5, 1, 10, false},
+		{"at min", 1, 1, 10, false},
+		{"at max", 10, 1, 10, false},
+		{"below range", 0, 1, 10, true},
+		{"above range", 11, 1, 10, true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := Range(tt.min, tt.max)(tt.value)
+			if (err != nil) != tt.wantError {
+				t.Errorf("Range() error = %v, wantError %v", err, tt.wantError)
+			}
+		})
+	}
+}