Parse break statements

5 files changed, 52 insertions, 4 deletions

diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedBreakNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedBreakNode.java
new file mode 100644
index 00000000..d57a7367
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedBreakNode.java
@@ -0,0 +1,15 @@
+package org.shedlang.compiler.ast.untyped;
+
+import org.shedlang.compiler.sources.Source;
+
+import java.util.Optional;
+
+public record UntypedBreakNode(
+    Optional<UntypedExpressionNode> expression,
+    Source source
+) implements UntypedFunctionStatementNode {
+    @Override
+    public UntypedFunctionStatementBehaviour behaviour() {
+        return UntypedFunctionStatementBehaviour.TERMINATE;
+    }
+}
diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionStatementNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionStatementNode.java
index 09eb4909..2ca95b2b 100644
--- a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionStatementNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionStatementNode.java
@@ -1,5 +1,5 @@
 package org.shedlang.compiler.ast.untyped;
 
-public sealed interface UntypedFunctionStatementNode extends UntypedNode permits UntypedAssignNode, UntypedBlockReturnNode, UntypedExpressionStatementNode, UntypedFunctionReturnNode, UntypedResumeNode, UntypedWhileNode {
+public sealed interface UntypedFunctionStatementNode extends UntypedNode permits UntypedAssignNode, UntypedBlockReturnNode, UntypedBreakNode, UntypedExpressionStatementNode, UntypedFunctionReturnNode, UntypedResumeNode, UntypedWhileNode {
     UntypedFunctionStatementBehaviour behaviour();
 }
diff --git a/src/main/java/org/shedlang/compiler/parser/Parser.java b/src/main/java/org/shedlang/compiler/parser/Parser.java
index 7b7e8358..1d56120b 100644
--- a/src/main/java/org/shedlang/compiler/parser/Parser.java
+++ b/src/main/java/org/shedlang/compiler/parser/Parser.java
@@ -171,6 +171,23 @@ public class Parser {
         return new UntypedBoolLiteralNode(value, source);
     }
 
+    private static UntypedFunctionStatementNode parseBreak(TokenIterator<TokenType> tokens) {
+        var start = tokens.position();
+
+        tokens.skip(TokenType.KEYWORD_BREAK);
+
+        var expression = tokens.isNext(TokenType.SYMBOL_SEMICOLON)
+            ? Optional.<UntypedExpressionNode>empty()
+            : Optional.of(parseTopLevelExpression(tokens));
+
+        tokens.skip(TokenType.SYMBOL_SEMICOLON);
+
+        var end = tokens.position();
+        var source = start.to(end);
+
+        return new UntypedBreakNode(expression, source);
+    }
+
     private static class CallParser implements OperationParser {
         @Override
         public OperatorPrecedence precedence() {
@@ -463,6 +480,9 @@ public class Parser {
             case KEYWORD_ASSIGN, KEYWORD_VAL, KEYWORD_VAR, SYMBOL_UNDERSCORE ->
                 parseAssign(tokens);
 
+            case KEYWORD_BREAK ->
+                parseBreak(tokens);
+
             case KEYWORD_RESUME ->
                 parseResume(tokens);
 
diff --git a/src/main/java/org/shedlang/compiler/typechecker/DeclaredVariables.java b/src/main/java/org/shedlang/compiler/typechecker/DeclaredVariables.java
index 41a9a421..2a842d93 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/DeclaredVariables.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/DeclaredVariables.java
@@ -35,6 +35,9 @@ class DeclaredVariables {
             case UntypedBlockReturnNode blockReturn ->
                 variables;
 
+            case UntypedBreakNode break_ ->
+                variables;
+
             case UntypedExpressionStatementNode expressionStatement ->
                 variables;
 
diff --git a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
index ca8f89ec..e7052ba3 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
@@ -276,6 +276,13 @@ public class TypeChecker {
         ));
     }
 
+    private static TypeCheckerResult<? extends TypedFunctionStatementNode> typeCheckBreak(
+        UntypedBreakNode untyped,
+        TypeCheckerContext context
+    ) {
+        throw new UnsupportedOperationException("TODO");
+    }
+
     private static TypeCheckerResult<TypedExpressionNode> typeCheckCall(
         UntypedCallNode untyped,
         TypeCheckerContext context
@@ -978,18 +985,21 @@ public class TypeChecker {
             case UntypedAssignNode assign ->
                 typeCheckAssign(assign, context);
 
-            case UntypedResumeNode resume ->
-                typeCheckResume(resume, context);
-
             case UntypedBlockReturnNode blockReturn ->
                 typeCheckBlockReturn(blockReturn, context);
 
+            case UntypedBreakNode break_ ->
+                typeCheckBreak(break_, context);
+
             case UntypedExpressionStatementNode expressionStatement ->
                 typeCheckExpressionStatement(expressionStatement, context);
 
             case UntypedFunctionReturnNode functionReturn ->
                 typeCheckFunctionReturn(functionReturn, context);
 
+            case UntypedResumeNode resume ->
+                typeCheckResume(resume, context);
+
             case UntypedWhileNode while_ ->
                 typeCheckWhile(while_, context);
         };