feat: add strutil (#10)

* add strutil

* add strutil unit tests

* update strutil unit tests

strutil/doc.go

@@ -0,0 +1,2 @@
+// Package strutil is common string utils for Go.
+package strutil

strutil/str.go

@@ -0,0 +1,20 @@
+package strutil
+
+import "strings"
+
+// EqualsIgnoreCase check if str1 is equal to str2 ignoring case sensitivity
+func EqualsIgnoreCase(str1, str2 string) bool {
+	// SA6005 - Inefficient string comparison with strings.ToLower or strings.ToUpper
+	// if strings.ToLower(s1) == strings.ToLower(s2) { ... }
+	return strings.EqualFold(str1, str2)
+}
+
+// ContainsIgnoreCase check if str1 contains str2 ignoring case sensitivity
+func ContainsIgnoreCase(str1, str2 string) bool {
+	return strings.Contains(strings.ToLower(str1), strings.ToLower(str2))
+}
+
+// IsEmpty check if value is empty string or blank string.
+func IsEmpty(str string) bool {
+	return strings.TrimSpace(str) == ""
+}

strutil/str_test.go

@@ -0,0 +1,68 @@
+package strutil
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestContainsIgnoreCase(t *testing.T) {
+	tests := []struct {
+		title    string
+		input    string
+		input2   string
+		expected bool
+	}{
+		{"should be true", "test lower case", "LoWer", true},
+		{"should be false", "test lower case", "LLL", false},
+		{"should be true", "TEST UPPER CASE", "upper", true},
+	}
+
+	for _, v := range tests {
+		t.Run(fmt.Sprintf("'%s' contains '%s' %s", v.input, v.input2, v.title), func(t *testing.T) {
+			got := ContainsIgnoreCase(v.input, v.input2)
+			assert.Equal(t, v.expected, got)
+		})
+	}
+}
+
+func TestEqualsIgnoreCase(t *testing.T) {
+	tests := []struct {
+		title    string
+		input    string
+		input2   string
+		expected bool
+	}{
+		{"should be true", "lower", "LoWer", true},
+		{"should be true", "lower", "LOWER", true},
+		{"should be true", "UPPER", "upper", true},
+		{"should be false", "UPPER", "u", false},
+	}
+
+	for _, v := range tests {
+		t.Run(fmt.Sprintf("'%s' equals '%s' %s", v.input, v.input2, v.title), func(t *testing.T) {
+			got := EqualsIgnoreCase(v.input, v.input2)
+			assert.Equal(t, v.expected, got)
+		})
+	}
+}
+
+func TestIsEmpty(t *testing.T) {
+	tests := []struct {
+		title    string
+		input    string
+		expected bool
+	}{
+		{"should be empty", "", true},
+		{"blank string should be empty", "   ", true},
+		{"line break should be empty", "  \n ", true},
+	}
+
+	for _, v := range tests {
+		t.Run(v.title, func(t *testing.T) {
+			got := IsEmpty(v.input)
+			assert.Equal(t, v.expected, got)
+		})
+	}
+}