Updated tests.

Sources/LoxCore/Interpreter.swift

@@ -253,8 +253,8 @@ final class Interpreter: ExprVisitor, StmtVisitor {
     func visitCallExpr(_ expr: Expr.Call) -> ExprVisitorReturn {
         let calleeResult = evaluate(expr: expr.callee)
 
-        guard let callee = calleeResult?.value else {
-            return calleeResult
+        guard let callee = calleeResult?.value, let function = callee as? Callable else {
+            return .failure(InterpreterError.runtime(expr.paren, "Can only call functions and classes."))
         }
 
         var arguments: Array<Any> = []
@@ -266,10 +266,6 @@ final class Interpreter: ExprVisitor, StmtVisitor {
             arguments.append(arg)
         }
 
-        guard let function = callee as? Callable else {
-            return .failure(InterpreterError.runtime(expr.paren, "Can only call functions and classes."))
-        }
-
         guard arguments.count == function.arity else {
             return .failure(InterpreterError.runtime(expr.paren, "Expected \(function.arity) arguments but got \(arguments.count)."))
         }

Sources/LoxCore/Parser.swift

@@ -44,7 +44,8 @@ final class Parser {
 
     private func declaration() -> Stmt? {
         do {
-            if match(.fun) {
+            if check(.fun) && checkNext(.identifier) {
+                try consume(.fun, message: "")
                 return try function(kind: "function")
             }
             if match(.Var) {
@@ -374,7 +375,8 @@ final class Parser {
             return Expr.Grouping(expression: expr)
         }
 
-        if match(.fun) {
+        if check(.fun) && checkNext(.leftParen) {
+            try consume(.fun, message: "")
             return try functionBody(kind: "function")
         }
 
@@ -422,6 +424,12 @@ extension Parser {
         return peek().type == tokenType
     }
 
+    func checkNext(_ tokenType: TokenType) -> Bool {
+        if isAtEnd() { return false }
+        if tokens[current + 1].type == .eof { return false }
+        return tokens[current + 1].type == tokenType
+    }
+
     func advance() -> Token {
         if !isAtEnd() {
             current += 1

temptest.lox

@@ -1,13 +1,15 @@
-fun repeat(times, fn) {
-    for (var i = 0; i < times; i = i + 1) {
-        fn();
-    }
-}
-
-var times = 10;
-repeat(times, fun () {
-    print("Repeating " + times + " times.");
-});
+fun () {};
+
+// fun repeat(times, fn) {
+//     for (var i = 0; i < times; i = i + 1) {
+//         fn();
+//     }
+// }
+
+// var times = 10;
+// repeat(times, fun () {
+//     print("Repeating " + times + " times.");
+// });
 
 // fun sayHi(first, last) {
 //   print "Hi, " + first + " " + last + "!";

test/constructor/default_arguments.lox

@@ -1,4 +1,3 @@
 class Foo {}
 
-var foo = Foo(1, 2, 3);
-print foo; // expect: Foo instance
+var foo = Foo(1, 2, 3); // expect runtime error: Expected 0 arguments but got 3.

test/constructor/extra_arguments.lox

@@ -1,11 +1,8 @@
 class Foo {
   init(a, b) {
-    print "init"; // expect: init
     this.a = a;
     this.b = b;
   }
 }
 
-var foo = Foo(1, 2, 3, 4);
-print foo.a; // expect: 1
-print foo.b; // expect: 2
+var foo = Foo(1, 2, 3, 4); // expect runtime error: Expected 2 arguments but got 4.

test/constructor/missing_arguments.lox

@@ -2,4 +2,4 @@ class Foo {
   init(a, b) {}
 }
 
-var foo = Foo(1); // expect runtime error: Not enough arguments.
+var foo = Foo(1); // expect runtime error: Expected 2 arguments but got 1.

test/function/body_must_be_block.lox

@@ -1,3 +1,5 @@
-// [line 3] Error at '123': Expect '{' before block.
-// [c line 4] Error at end: Expect '}' after block.
+// original was -> [line 3] Error at '123': Expect '{' before block.
+// but because we support lambdas the error is slightly different:
+// [line 5] Error at '123': Expect '{' before function body.
+// ?? [c line 4] Error at end: Expect '}' after block.
 fun f() 123;

test/function/extra_arguments.lox

@@ -1,6 +1,6 @@
 fun f(a, b) {
-  print a; // expect: 1
-  print b; // expect: 2
+  print a;
+  print b;
 }
 
-f(1, 2, 3, 4);
+f(1, 2, 3, 4); // expect runtime error: Expected 2 arguments but got 4.

test/function/missing_arguments.lox

@@ -1,3 +1,3 @@
 fun f(a, b) {}
 
-f(1); // expect runtime error: Not enough arguments.
+f(1); // expect runtime error: Expected 2 arguments but got 1.

test/function/print.lox

@@ -0,0 +1,2 @@
+fun foo() {}
+print foo; // expect: <fn foo>

test/method/extra_arguments.lox

@@ -1,8 +1,8 @@
 class Foo {
   method(a, b) {
-    print a; // expect: 1
-    print b; // expect: 2
+    print a;
+    print b;
   }
 }
 
-Foo().method(1, 2, 3, 4);
+Foo().method(1, 2, 3, 4); // expect runtime error: Expected 2 arguments but got 4.

test/method/missing_arguments.lox

@@ -2,4 +2,4 @@ class Foo {
   method(a, b) {}
 }
 
-Foo().method(1); // expect runtime error: Not enough arguments.
+Foo().method(1); // expect runtime error: Expected 2 arguments but got 1.

test/operator/add_bool_string.lox

@@ -1 +1,2 @@
-true + "s"; // expect runtime error: Operands must be two numbers or two strings.
+// No error here, Chapter 7 challenge 2 implemented.
+// true + "s"; expect runtime error: Operands must be two numbers or two strings.

test/super/extra_arguments.lox

@@ -6,11 +6,9 @@ class Base {
 
 class Derived < Base {
   foo() {
-    print "Derived.foo()";
-    super.foo("a", "b", "c", "d");
+    print "Derived.foo()"; // expect: Derived.foo()
+    super.foo("a", "b", "c", "d"); // expect runtime error: Expected 2 arguments but got 4.
   }
 }
 
 Derived().foo();
-// expect: Derived.foo()
-// expect: Base.foo(a, b)

test/super/missing_arguments.lox

@@ -6,7 +6,7 @@ class Base {
 
 class Derived < Base {
   foo() {
-    super.foo(1); // expect runtime error: Not enough arguments.
+    super.foo(1); // expect runtime error: Expected 2 arguments but got 1.
   }
 }
 

test/unexpected_character.lox

@@ -1,3 +1,3 @@
-// [line 3] Error: Unexpected character.
+// [line 3] Error: Unexpected character. '|'
 // [java line 3] Error at 'b': Expect ')' after arguments.
 foo(a | b);

tools/test_chap10challenge2_and_chap7challenge2patch.diff

@@ -0,0 +1,30 @@
+diff --git a/test/function/body_must_be_block.lox b/test/function/body_must_be_block.lox
+index 745a8d0..16f0337 100755
+--- a/test/function/body_must_be_block.lox
++++ b/test/function/body_must_be_block.lox
+@@ -1,3 +1,5 @@
+-// [line 3] Error at '123': Expect '{' before block.
+-// [c line 4] Error at end: Expect '}' after block.
++// original was -> [line 3] Error at '123': Expect '{' before block.
++// but because we support lambdas the error is slightly different:
++// [line 5] Error at '123': Expect '{' before function body.
++// ?? [c line 4] Error at end: Expect '}' after block.
+ fun f() 123;
+diff --git a/test/operator/add_bool_string.lox b/test/operator/add_bool_string.lox
+index 04739d5..0c8c87a 100755
+--- a/test/operator/add_bool_string.lox
++++ b/test/operator/add_bool_string.lox
+@@ -1 +1,2 @@
+-true + "s"; // expect runtime error: Operands must be two numbers or two strings.
++// No error here, Chapter 7 challenge 2 implemented.
++// true + "s"; expect runtime error: Operands must be two numbers or two strings.
+\ No newline at end of file
+diff --git a/test/unexpected_character.lox b/test/unexpected_character.lox
+index 5e51396..9ca1244 100755
+--- a/test/unexpected_character.lox
++++ b/test/unexpected_character.lox
+@@ -1,3 +1,3 @@
+-// [line 3] Error: Unexpected character.
++// [line 3] Error: Unexpected character. '|'
+ // [java line 3] Error at 'b': Expect ')' after arguments.
+ foo(a | b);