Add Buildable gyb

Author: kimdv

Sources/SwiftSyntaxBuilder/DeclBuildables.swift renamed to Sources/SwiftSyntaxBuilder/DeclBuildables.swift.gyb

@@ -1,3 +1,10 @@
+%{
+  from gyb_syntax_support import *
+  from gyb_syntax_support.kinds import lowercase_first_word, kind_to_type
+  # -*- mode: Swift -*-
+  # Ignore the following admonition it applies to the resulting .swift file only
+}%
+//// Automatically Generated From DeclBuildables.swift.gyb.
 //===----------------------------------------------------------------------===//
 //
 // This source file is part of the Swift.org open source project
@@ -185,3 +192,55 @@ public struct Struct: DeclBuildable {
     return DeclSyntax(structDecl)
   }
 }
+
+// MARK: Generated
+
+% for node in SYNTAX_NODES:
+%   if node.is_buildable():
+%     protocol = 'SyntaxBuildable'
+%     return_type = 'Syntax'
+%     build_type = 'Syntax'
+%     if node.base_kind == 'Expr':
+%       protocol = 'ExprBuildable'
+%       return_type = 'ExprSyntax'
+%       build_type = 'Expr'
+%     elif node.base_kind == 'Decl':
+%       protocol = 'DeclBuildable'
+%       return_type = 'DeclSyntax'
+%       build_type = 'Decl'
+%     end
+public struct ${node.syntax_kind}: ${protocol} {
+%     child_params = []
+%     for child in node.children:
+%         param_type = child.type_name
+%         if child.is_optional:
+%            param_type = param_type + "?"
+%         end
+%         child_params.append("%s: %s" % (child.swift_name, param_type))
+%     end
+%     for child_param in child_params:
+  let ${child_param}
+%     end
+
+  public init(
+    ${',\n    '.join(child_params)}
+  ) {
+%     for child in node.children:
+    self.${lowercase_first_word(child.name)} = ${lowercase_first_word(child.name)}
+%     end
+  }
+
+  public func build${build_type}(format: Format, leadingTrivia: Trivia) -> ${return_type} {
+    let ${node.swift_syntax_kind} = SyntaxFactory.make${node.syntax_kind}(
+%     child_params = []
+%     for child in node.children:
+%       child_params.append("%s: %s" % (child.swift_name, child.swift_name))
+%     end
+      ${',\n      '.join(child_params)}
+    ).withLeadingTrivia(leadingTrivia)
+    return ${return_type}(${node.swift_syntax_kind})
+  }
+}
+
+%   end
+% end