Add mechanism to escape C# keywords for path parts (#5563)

Author: stevejgordon

src/ApiGenerator/Domain/Code/LowLevel/LowLevelClientMethod.cs

@@ -33,9 +33,8 @@ public string UrlInCode
 			{
 				string Evaluator(Match m)
 				{
-
 					var arg = m.Groups[^1].Value.ToCamelCase();
-					return $"{{{arg}:{arg}}}";
+					return $"{{{arg.ReservedKeywordReplacer()}:{arg}}}";
 				}
 
 				var url = Path.TrimStart('/');

src/ApiGenerator/Domain/Specification/UrlPart.cs

@@ -139,17 +139,14 @@ public string InterfaceName
 		}
 
 		public string Name { get; set; }
-		public string NameAsArgument => Name.ToCamelCase();
+		public string NameAsArgument => Name.ToCamelCase().ReservedKeywordReplacer();
 		public IEnumerable<string> Options { get; set; }
 		public bool Required { get; set; }
 		public bool Deprecated { get; set; }
 		public string Type { get; set; }
 
-		private string CleanUpDescription(string value)
-		{
-			if (string.IsNullOrWhiteSpace(value)) return value;
 
-			return value.Replace("use `_all` or empty string", "use the special string `_all` or Indices.All");
-		}
+
+		private static string CleanUpDescription(string value) => string.IsNullOrWhiteSpace(value) ? value : value.Replace("use `_all` or empty string", "use the special string `_all` or Indices.All");
 	}
 }

src/ApiGenerator/Domain/Specification/UrlPath.cs

@@ -55,25 +55,24 @@ orderby path.IndexOf($"{{{name}}}", StringComparison.Ordinal)
 
 		public string TypedSubClassBaseArguments => string.Join(", ", Parts.Select(p => p.NameAsArgument));
 
-		private static string[] ResolvabeFromT = { "index"};
+		private static readonly string[] ResolvableFromT = { "index"};
 
+		public bool HasResolvableArguments => Parts.Any(p => ResolvableFromT.Contains(p.Name));
+		public string AutoResolveConstructorArguments => string.Join(", ", Parts.Where(p  => !ResolvableFromT.Contains(p.Name)).Select(p => $"{p.HighLevelTypeName} {p.NameAsArgument}"));
 
-		public bool HasResolvableArguments => Parts.Any(p => ResolvabeFromT.Contains(p.Name));
-		public string AutoResolveConstructorArguments => string.Join(", ", Parts.Where(p  => !ResolvabeFromT.Contains(p.Name)).Select(p => $"{p.HighLevelTypeName} {p.NameAsArgument}"));
-
-		public string AutoResolveBaseArguments(string generic) => string.Join(", ", Parts.Select(p => !ResolvabeFromT.Contains(p.Name) ? p.Name : $"typeof({generic})"));
+		public string AutoResolveBaseArguments(string generic) => string.Join(", ", Parts.Select(p => !ResolvableFromT.Contains(p.Name) ? p.Name : $"typeof({generic})"));
 
 		public string DocumentPathBaseArgument(string generic) => string.Join(", ",
 			_additionalPartsForConstructor.Select(p => p.Name =="id" ? $"id ?? Nest.Id.From(documentWithId)"
-				: ResolvabeFromT.Contains(p.Name) ? $"{p.Name} ?? typeof({generic})" : p.Name));
+				: ResolvableFromT.Contains(p.Name) ? $"{p.Name} ?? typeof({generic})" : p.Name));
 
 		public string DocumentPathConstructorArgument(string generic) => string.Join(", ",
 			new [] { $"{generic} documentWithId" }.Concat(_additionalPartsForConstructor.Select(p => $"{p.HighLevelTypeName} {p.NameAsArgument} = null")));
 
 		public string GetXmlDocs(string indent, bool skipResolvable = false, bool documentConstructor = false)
 		{
 			var doc = $@"///<summary>{Path}</summary>";
-			var parts = Parts.Where(p => !skipResolvable || !ResolvabeFromT.Contains(p.Name)).ToList();
+			var parts = Parts.Where(p => !skipResolvable || !ResolvableFromT.Contains(p.Name)).ToList();
 			if (!parts.Any()) return doc;
 
 			doc += indent;

src/ApiGenerator/Extensions.cs

@@ -43,7 +43,10 @@ public static string ToCamelCase(this string s)
 			return pascal[0].ToLower() + pascal.Substring(1);
 		}
 
-		public static string SplitPascalCase(this string s) =>
-			Regex.Replace(s, "([A-Z]+[a-z]*)", " $1").Trim();
+		private static readonly Dictionary<string, string> ReservedNames = new() { { "namespace", "@namespace" } };
+
+		public static string ReservedKeywordReplacer(this string name) => ReservedNames.ContainsKey(name) ? ReservedNames[name] : name;
+		
+		public static string SplitPascalCase(this string s) => Regex.Replace(s, "([A-Z]+[a-z]*)", " $1").Trim();
 	}
 }