From 9781a28df7874e8d918fcbd67f8e686ddadd01a2 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Tue, 27 Aug 2019 12:31:02 -0300
Subject: [PATCH] add enum support

---
 examples/hello.v    |  6 ++++++
 src/ast.zig         | 20 ++++++++++++++++++++
 src/ast_printer.zig | 14 ++++++++++++++
 src/parser.zig      | 20 ++++++++++++++++++++
 4 files changed, 60 insertions(+)

diff --git a/examples/hello.v b/examples/hello.v
index ba91ed7..b0f03c1 100644
--- a/examples/hello.v
+++ b/examples/hello.v
@@ -79,3 +79,9 @@ pub mut:
 pub mut mut: 
 	f int
 }
+
+enum Color {
+	red green blue
+	cyan
+	alpha
+}
diff --git a/src/ast.zig b/src/ast.zig
index bbb4956..773d9c5 100644
--- a/src/ast.zig
+++ b/src/ast.zig
@@ -5,6 +5,7 @@ const Token = tokens.Token;
 pub const NodeList = std.ArrayList(*Node);
 pub const StmtList = std.ArrayList(*Stmt);
 pub const ExprList = std.ArrayList(*Expr);
+pub const TokenList = std.ArrayList(Token);
 pub const ParamList = std.ArrayList(ParamDecl);
 pub const ConstList = std.ArrayList(SingleConst);
 
@@ -13,6 +14,7 @@ pub const NodeType = enum {
     FnDecl,
     ConstDecl,
     Struct,
+    Enum,
     Block,
     Stmt,
 };
@@ -239,11 +241,17 @@ pub const Struct = struct {
     fields: FieldList,
 };
 
+pub const Enum = struct {
+    name: Token,
+    fields: TokenList,
+};
+
 pub const Node = union(NodeType) {
     Root: NodeList,
     FnDecl: FnDecl,
     ConstDecl: ConstList,
     Struct: Struct,
+    Enum: Enum,
 
     Block: StmtList,
 
@@ -266,4 +274,16 @@ pub const Node = union(NodeType) {
 
         return node;
     }
+
+    pub fn mkEnumDecl(allocator: *std.mem.Allocator, name: Token, fields: TokenList) !*Node {
+        var node = try allocator.create(Node);
+        node.* = Node{
+            .Enum = Enum{
+                .name = name,
+                .fields = fields,
+            },
+        };
+
+        return node;
+    }
 };
diff --git a/src/ast_printer.zig b/src/ast_printer.zig
index 5e41240..6360035 100644
--- a/src/ast_printer.zig
+++ b/src/ast_printer.zig
@@ -81,6 +81,20 @@ pub fn printNode(node: *Node, ident: usize) void {
             print(ident, "))\n");
         },
 
+        .Enum => |decl| {
+            print(ident, "(enum {} (\n", decl.name.lexeme);
+
+            for (decl.fields.toSlice()) |field| {
+                print(
+                    ident + 1,
+                    "{}\n",
+                    field.lexeme,
+                );
+            }
+
+            print(ident, "))\n");
+        },
+
         .Root => {
             for (node.Root.toSlice()) |child| {
                 printNode(child, ident + 1);
diff --git a/src/parser.zig b/src/parser.zig
index 0675378..197b69f 100644
--- a/src/parser.zig
+++ b/src/parser.zig
@@ -582,11 +582,31 @@ pub const Parser = struct {
         }
     }
 
+    fn parseEnumDecl(self: *@This()) !*Node {
+        _ = try self.consumeSingle(.Enum);
+
+        var fields = ast.TokenList.init(self.allocator);
+        errdefer fields.deinit();
+
+        const name = try self.consumeSingle(.Identifier);
+
+        _ = try self.consumeSingle(.LeftBrace);
+
+        while (!self.check(.RightBrace)) {
+            try fields.append(try self.consumeSingle(.Identifier));
+        }
+
+        _ = try self.consumeSingle(.RightBrace);
+
+        return try Node.mkEnumDecl(self.allocator, name, fields);
+    }
+
     fn parseTopDecl(self: *@This()) !*Node {
         return switch (self.peek().ttype) {
             .Fn => try self.parseFnDecl(),
             .Const => try self.parseConstDecl(),
             .Struct => try self.parseStructDecl(),
+            .Enum => try self.parseEnumDecl(),
 
             else => |ttype| blk: {
                 self.doError("expected Fn, Const, Struct, got {}\n", ttype);