Use case sensitivity when parsing string to TimeUnit enum

Author: russcam

Diff for: src/Nest/CommonAbstractions/Extensions/Extensions.cs

@@ -72,7 +72,7 @@ internal static IEnumerable<T> DistinctBy<T, TKey>(this IEnumerable<T> items, Fu
 		}
 
 		internal static ConcurrentDictionary<string, object> _enumCache = new ConcurrentDictionary<string, object>();
-		internal static T? ToEnum<T>(this string str) where T : struct
+		internal static T? ToEnum<T>(this string str, StringComparison comparison = StringComparison.OrdinalIgnoreCase) where T : struct
 		{
 			var enumType = typeof(T);
 			var key = $"{enumType.Name}.{str}";
@@ -82,7 +82,7 @@ internal static IEnumerable<T> DistinctBy<T, TKey>(this IEnumerable<T> items, Fu
 
 			foreach (var name in Enum.GetNames(enumType))
 			{
-				if (name.Equals(str, StringComparison.OrdinalIgnoreCase))
+				if (name.Equals(str, comparison))
 				{
 					var v = (T)Enum.Parse(enumType, name, true);
 					_enumCache.TryAdd(key, v);
@@ -99,7 +99,6 @@ internal static IEnumerable<T> DistinctBy<T, TKey>(this IEnumerable<T> items, Fu
 				}
 
 				var alternativeEnumMemberAttribute = enumFieldInfo.GetCustomAttribute<AlternativeEnumMemberAttribute>();
-
 				if (alternativeEnumMemberAttribute?.Value == str)
 				{
 					var v = (T) Enum.Parse(enumType, name);

Diff for: src/Nest/CommonOptions/DateMath/DateMath.cs

@@ -71,7 +71,7 @@ public static DateMath FromString(string dateMath)
 
 			if (match.Groups["rounding"].Success)
 			{
-				var rounding = match.Groups["rounding"].Value.Substring(1).ToEnum<TimeUnit>();
+				var rounding = match.Groups["rounding"].Value.Substring(1).ToEnum<TimeUnit>(StringComparison.Ordinal);
 				if (rounding.HasValue)
 					return math.RoundTo(rounding.Value);
 			}

Diff for: src/Nest/CommonOptions/TimeUnit/Time.cs

@@ -51,7 +51,7 @@ public Time(string timeUnit)
 
 			this.Factor = double.Parse(match.Groups["factor"].Value, CultureInfo.InvariantCulture);
 			this.Interval = match.Groups["interval"].Success
-				? match.Groups["interval"].Value.ToEnum<TimeUnit>()
+				? match.Groups["interval"].Value.ToEnum<TimeUnit>(StringComparison.Ordinal)
 				: TimeUnit.Millisecond;
 
 			this.Milliseconds = GetMilliseconds(this.Interval.Value, this.Factor.Value);