Add validator lib

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

pkg/validator/checkeach_slice_test.go

@@ -0,0 +1,201 @@
+// 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"
+)
+
+// CustomType simulates types like gid.GID
+type CustomType string
+
+func TestCheckEach_EmptyTypedSlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with []gid.GID{} (empty slice of custom type)
+	emptySlice := []CustomType{}
+
+	v.CheckEach(emptySlice, "items", func(index int, item any) {
+		// This callback should never be called for an empty slice
+		t.Error("callback should not be called for empty slice")
+	})
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error for empty slice: %v", v.Error())
+	}
+}
+
+func TestCheckEach_NonEmptyTypedSlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with []gid.GID{"abc", "def"}
+	slice := []CustomType{"abc", "def"}
+
+	callCount := 0
+	v.CheckEach(slice, "items", func(index int, item any) {
+		callCount++
+		// Verify the item is the correct type
+		str, ok := item.(CustomType)
+		if !ok {
+			t.Errorf("expected CustomType, got %T", item)
+		}
+		if index == 0 && str != "abc" {
+			t.Errorf("expected 'abc', got %s", str)
+		}
+		if index == 1 && str != "def" {
+			t.Errorf("expected 'def', got %s", str)
+		}
+	})
+
+	if callCount != 2 {
+		t.Errorf("expected callback to be called 2 times, got %d", callCount)
+	}
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error: %v", v.Error())
+	}
+}
+
+func TestCheckEach_NilTypedSlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with var x []gid.GID (nil slice)
+	var nilSlice []CustomType
+
+	v.CheckEach(nilSlice, "items", func(index int, item any) {
+		// This callback should never be called for a nil slice
+		t.Error("callback should not be called for nil slice")
+	})
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error for nil slice: %v", v.Error())
+	}
+}
+
+func TestCheckEach_PointerToNonEmptySlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with *[]gid.GID (pointer to slice)
+	slice := []CustomType{"abc", "def", "ghi"}
+	ptrToSlice := &slice
+
+	callCount := 0
+	v.CheckEach(ptrToSlice, "items", func(index int, item any) {
+		callCount++
+		str, ok := item.(CustomType)
+		if !ok {
+			t.Errorf("expected CustomType, got %T", item)
+		}
+		expectedValues := []CustomType{"abc", "def", "ghi"}
+		if str != expectedValues[index] {
+			t.Errorf("at index %d: expected %s, got %s", index, expectedValues[index], str)
+		}
+	})
+
+	if callCount != 3 {
+		t.Errorf("expected callback to be called 3 times, got %d", callCount)
+	}
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error for pointer to slice: %v", v.Error())
+	}
+}
+
+func TestCheckEach_PointerToEmptySlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with *[]gid.GID{} (pointer to empty slice)
+	slice := []CustomType{}
+	ptrToSlice := &slice
+
+	v.CheckEach(ptrToSlice, "items", func(index int, item any) {
+		t.Error("callback should not be called for empty slice")
+	})
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error for pointer to empty slice: %v", v.Error())
+	}
+}
+
+func TestCheckEach_NilPointerToSlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with var x *[]gid.GID (nil pointer to slice)
+	var nilPtrToSlice *[]CustomType
+
+	v.CheckEach(nilPtrToSlice, "items", func(index int, item any) {
+		t.Error("callback should not be called for nil pointer to slice")
+	})
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error for nil pointer to slice: %v", v.Error())
+	}
+}
+
+func TestCheckEach_DoublePointerToSlice(t *testing.T) {
+	v := New()
+
+	// Simulate what happens with **[]gid.GID (double pointer to slice)
+	slice := []CustomType{"x", "y"}
+	ptrToSlice := &slice
+	doublePtrToSlice := &ptrToSlice
+
+	callCount := 0
+	v.CheckEach(doublePtrToSlice, "items", func(index int, item any) {
+		callCount++
+		str, ok := item.(CustomType)
+		if !ok {
+			t.Errorf("expected CustomType, got %T", item)
+		}
+		expectedValues := []CustomType{"x", "y"}
+		if str != expectedValues[index] {
+			t.Errorf("at index %d: expected %s, got %s", index, expectedValues[index], str)
+		}
+	})
+
+	if callCount != 2 {
+		t.Errorf("expected callback to be called 2 times, got %d", callCount)
+	}
+
+	if v.HasErrors() {
+		t.Errorf("unexpected error for double pointer to slice: %v", v.Error())
+	}
+}
+
+func TestCheckEach_NonSliceValue(t *testing.T) {
+	v := New()
+
+	// Pass a non-slice value
+	notASlice := "this is a string"
+
+	v.CheckEach(notASlice, "items", func(index int, item any) {
+		t.Error("callback should not be called for non-slice value")
+	})
+
+	if !v.HasErrors() {
+		t.Error("expected error for non-slice value")
+	}
+
+	errors := v.Errors()
+	if len(errors) != 1 {
+		t.Errorf("expected 1 error, got %d", len(errors))
+	}
+	if errors[0].Code != ErrorCodeInvalidFormat {
+		t.Errorf("expected error code %s, got %s", ErrorCodeInvalidFormat, errors[0].Code)
+	}
+	if errors[0].Message != "expected a slice" {
+		t.Errorf("expected message 'expected a slice', got '%s'", errors[0].Message)
+	}
+}