Added more tests

src/build/ast/EachInstruction.go

@@ -54,5 +54,9 @@ func EachInstruction(body token.List, call func(token.List) error) error {
 		}
 	}
 
+	if start != len(body) {
+		return call(body[start:])
+	}
+
 	return nil
 }

src/build/ast/parseKeyword.go

@@ -63,7 +63,13 @@ func parseKeyword(tokens token.List, source []byte, nodes AST) (Node, error) {
 			return nil, errors.New(errors.MissingBlockEnd, nil, tokens[len(tokens)-1].End())
 		}
 
-		cases, err := parseSwitch(tokens[blockStart+1:blockEnd], source)
+		body := tokens[blockStart+1 : blockEnd]
+
+		if len(body) == 0 {
+			return nil, errors.New(errors.EmptySwitch, nil, tokens[0].Position)
+		}
+
+		cases, err := parseSwitch(body, source)
 		return &Switch{Cases: cases}, err
 
 	default:

src/build/errors/CompileErrors.go

@@ -1,6 +1,7 @@
 package errors
 
 var (
+	EmptySwitch          = &Base{"Empty switch"}
 	ExpectedIfBeforeElse = &Base{"Expected an 'if' block before 'else'"}
 	InvalidNumber        = &Base{"Invalid number"}
 	InvalidExpression    = &Base{"Invalid expression"}

src/build/token/List.go

@@ -1,5 +1,9 @@
 package token
 
+import (
+	"strings"
+)
+
 // List is a slice of tokens.
 type List []Token
 
@@ -24,3 +28,14 @@ func (list List) LastIndexKind(kind Kind) int {
 
 	return -1
 }
+
+// Text returns the concatenated token text.
+func (list List) Text(source []byte) string {
+	tmp := strings.Builder{}
+
+	for _, t := range list {
+		tmp.WriteString(t.Text(source))
+	}
+
+	return tmp.String()
+}