From 4b48ef1a75165bfe98fb604bccf458fb37597605 Mon Sep 17 00:00:00 2001
From: alpha <alpha@kejadlen.dev>
Date: Mon, 15 Aug 2022 23:17:37 +0000
Subject: [PATCH 1/4] 10.1

FossilOrigin-Name: c1d35386c76ad60362ec68d9e94a6e4fe9cfc02c39b7c2589668a214a3f22c43
---
 ruby/lib/lox/ast_printer.rb  |  4 ++++
 ruby/lib/lox/expr.rb         |  1 +
 ruby/lib/lox/parser.rb       | 30 +++++++++++++++++++++++++++++-
 ruby/test/lox/test_parser.rb |  6 ++++++
 4 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/ruby/lib/lox/ast_printer.rb b/ruby/lib/lox/ast_printer.rb
index a303c5f..154c9b9 100644
--- a/ruby/lib/lox/ast_printer.rb
+++ b/ruby/lib/lox/ast_printer.rb
@@ -36,6 +36,10 @@ module Lox
       expr.expr.accept(self)
     end
 
+    def visit_call(call)
+      parenthesize(call.callee.accept(self), *call.args)
+    end
+
     private
 
     def parenthesize(name, *exprs)
diff --git a/ruby/lib/lox/expr.rb b/ruby/lib/lox/expr.rb
index 2737930..a3f40a2 100644
--- a/ruby/lib/lox/expr.rb
+++ b/ruby/lib/lox/expr.rb
@@ -12,6 +12,7 @@ module Lox
 
     expr :Assign, :name, :value
     expr :Binary, :left, :op, :right
+    expr :Call, :callee, :paren, :args
     expr :Grouping, :expr
     expr :Literal, :value
     expr :Logical, :left, :op, :right
diff --git a/ruby/lib/lox/parser.rb b/ruby/lib/lox/parser.rb
index 0f6ce9f..c6e8e24 100644
--- a/ruby/lib/lox/parser.rb
+++ b/ruby/lib/lox/parser.rb
@@ -215,13 +215,41 @@ module Lox
     end
 
     def unary
-      return primary unless match?(:BANG, :MINUS)
+      return call unless match?(:BANG, :MINUS)
 
       op = prev
       right = unary
       Expr::Unary.new(op, right)
     end
 
+    def call
+      expr = primary
+
+      loop do
+        if match?(:LEFT_PAREN)
+          expr = finish_call(expr)
+        else
+          break
+        end
+      end
+
+      expr
+    end
+
+    def finish_call(callee)
+      args = []
+      if !check?(:RIGHT_PAREN)
+        loop do
+          args << expression
+          break unless match?(:COMMA)
+        end
+      end
+
+      paren = consume!(:RIGHT_PAREN, "Expect ')' after arguments.")
+
+      Expr::Call.new(callee, paren, args)
+    end
+
     def primary
       return Expr::Literal.new(false) if match?(:FALSE)
       return Expr::Literal.new(true) if match?(:TRUE)
diff --git a/ruby/test/lox/test_parser.rb b/ruby/test/lox/test_parser.rb
index aaad61e..11a7904 100644
--- a/ruby/test/lox/test_parser.rb
+++ b/ruby/test/lox/test_parser.rb
@@ -75,6 +75,12 @@ class TestParser < Lox::Test
     SRC
   end
 
+  def test_call
+    assert_parsed "((var foo))", :statement, "foo();"
+    assert_parsed "((var foo) (var bar))", :statement, "foo(bar);"
+    assert_parsed "((var foo) (var bar) (var baz))", :statement, "foo(bar, baz);"
+  end
+
   private
 
   def assert_parsed(expected, name, src)

From 2a5230c9251970c2d1a444281b20d354037550b9 Mon Sep 17 00:00:00 2001
From: alpha <alpha@kejadlen.dev>
Date: Mon, 15 Aug 2022 23:19:49 +0000
Subject: [PATCH 2/4] 10.1.1

FossilOrigin-Name: c0a4d7dadf87d80ec3d0b6ef67e74d6c49d3ff2efa3179acf0ed90599b476efd
---
 ruby/lib/lox/parser.rb | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/ruby/lib/lox/parser.rb b/ruby/lib/lox/parser.rb
index c6e8e24..1e14e53 100644
--- a/ruby/lib/lox/parser.rb
+++ b/ruby/lib/lox/parser.rb
@@ -16,6 +16,8 @@ module Lox
         statements << declaration
       end
       statements
+    rescue ParseError
+      synchronize!
     end
 
     private
@@ -24,8 +26,6 @@ module Lox
       return var_declaration if match?(:VAR)
 
       statement
-    rescue ParseError
-      synchronize!
     end
 
     def var_declaration
@@ -240,6 +240,8 @@ module Lox
       args = []
       if !check?(:RIGHT_PAREN)
         loop do
+          raise ParseError.new(peek,  "Can't have more than 255 arguments.") if args.size >= 255
+
           args << expression
           break unless match?(:COMMA)
         end

From 28b9fd32d027a059b84f2d1cfe9d59dd950536cd Mon Sep 17 00:00:00 2001
From: alpha <alpha@kejadlen.dev>
Date: Mon, 15 Aug 2022 23:22:11 +0000
Subject: [PATCH 3/4] 10.1.2

FossilOrigin-Name: fae7fe1a493cd7d2c31e140204cfd581080c6bf5a70ed967107a1a5237bed129
---
 ruby/lib/lox/interpreter.rb | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ruby/lib/lox/interpreter.rb b/ruby/lib/lox/interpreter.rb
index 90f087d..703389e 100644
--- a/ruby/lib/lox/interpreter.rb
+++ b/ruby/lib/lox/interpreter.rb
@@ -138,7 +138,13 @@ module Lox
         left * right
       else fail
       end
+    end
+
+    def visit_call(expr)
+      callee = evaluate(expr.callee)
+      args = expr.args.map { evaluate(_1) }
 
+      callee.call(self, args)
     end
 
     private

From fe7e9022117eb07a8d27965447741ae9712662fd Mon Sep 17 00:00:00 2001
From: alpha <alpha@kejadlen.dev>
Date: Mon, 15 Aug 2022 23:25:36 +0000
Subject: [PATCH 4/4] 10.1.4

FossilOrigin-Name: f49d9465e02a773fe8b1add8537291fd03620b1c6f14f3b0846a4aa4d362ee5f
---
 ruby/lib/lox/interpreter.rb | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/ruby/lib/lox/interpreter.rb b/ruby/lib/lox/interpreter.rb
index 703389e..28904cc 100644
--- a/ruby/lib/lox/interpreter.rb
+++ b/ruby/lib/lox/interpreter.rb
@@ -141,10 +141,13 @@ module Lox
     end
 
     def visit_call(expr)
-      callee = evaluate(expr.callee)
+      func = evaluate(expr.callee)
       args = expr.args.map { evaluate(_1) }
 
-      callee.call(self, args)
+      raise RuntimeError.new(expr.paren, "Can only call functions and classes.") unless func.respond_to?(:call)
+      raise RuntimeError.new(expr.paren, "Expected #{func.arity} arguments but got #{args.size}.") unless args.size == func.arity
+
+      func.call(self, args)
     end
 
     private