lib/ini: add function IsValidVarName

The IsValidVarName check if "v" is valid variable name, where the
first character must be a letter and the rest should contains only
letter, digit, period, hyphen, or underscore.
If "v" is valid it will return true.

2 files changed, 40 insertions, 0 deletions

diff --git a/lib/ini/common.go b/lib/ini/common.go
index 82ed27c4..efe6efe0 100644
--- a/lib/ini/common.go
+++ b/lib/ini/common.go
@@ -6,9 +6,30 @@ package ini
 
 import (
 	"strings"
+	"unicode"
 )
 
 //
+// IsValidVarName check if "v" is valid variable name, where the
+// first character must be a letter and the rest should contains only letter,
+// digit, period, hyphen, or underscore.
+// If "v" is valid it will return true.
+//
+func IsValidVarName(v string) bool {
+	for x, r := range v {
+		if x == 0 && !unicode.IsLetter(r) {
+			return false
+		}
+		if unicode.IsLetter(r) || unicode.IsDigit(r) ||
+			r == tokHyphen || r == tokDot || r == tokUnderscore {
+			continue
+		}
+		return false
+	}
+	return true
+}
+
+//
 // IsValueBoolTrue will return true if variable contains boolean value for
 // true. The following conditions is boolean true for value: "" (empty
 // string), "true", "yes", "ya", "t", "1" (all of string is case insensitive).
diff --git a/lib/ini/common_example_test.go b/lib/ini/common_example_test.go
new file mode 100644
index 00000000..27149096
--- /dev/null
+++ b/lib/ini/common_example_test.go
@@ -0,0 +1,19 @@
+package ini
+
+import "fmt"
+
+func ExampleIsValidVarName() {
+	fmt.Println(IsValidVarName("1abcd"))
+	fmt.Println(IsValidVarName("-abcd"))
+	fmt.Println(IsValidVarName("_abcd"))
+	fmt.Println(IsValidVarName(".abcd"))
+	fmt.Println(IsValidVarName("a@bcd"))
+	fmt.Println(IsValidVarName("a-b_c.d"))
+	//Output:
+	//false
+	//false
+	//false
+	//false
+	//false
+	//true
+}