Throw error if function definition is missing param type

5 files changed, 39 insertions, 1 deletions

diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionDefinitionNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionDefinitionNode.java
index 769861a0..4d23f1c7 100644
--- a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionDefinitionNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionDefinitionNode.java
@@ -6,6 +6,8 @@ import org.shedlang.compiler.sources.Source;
 import org.shedlang.compiler.sources.Sources;
 import org.shedlang.compiler.types.Visibility;
 
+import java.util.Optional;
+
 public record UntypedFunctionDefinitionNode(
     String name,
     Visibility visibility,
@@ -48,6 +50,13 @@ public record UntypedFunctionDefinitionNode(
         }
 
         public Builder addPositionalParam(String name, UntypedTypeLevelExpressionNode type) {
+            return addPositionalParam(name, Optional.of(type));
+        }
+
+        public Builder addPositionalParam(
+            String name,
+            Optional<UntypedTypeLevelExpressionNode> type
+        ) {
             return new Builder(
                 this.name,
                 this.visibility,
diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionSignatureNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionSignatureNode.java
index 4920e253..d15c699d 100644
--- a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionSignatureNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedFunctionSignatureNode.java
@@ -40,7 +40,14 @@ public record UntypedFunctionSignatureNode(
         }
 
         public Builder addPositionalParam(String name, UntypedTypeLevelExpressionNode type) {
-            var paramNode = new UntypedParamNode(name, Optional.of(type), Sources.NULL);
+            return addPositionalParam(name, Optional.of(type));
+        }
+
+        public Builder addPositionalParam(
+            String name,
+            Optional<UntypedTypeLevelExpressionNode> type
+        ) {
+            var paramNode = new UntypedParamNode(name, type, Sources.NULL);
             return new Builder(
                 this.positionalParams.plus(paramNode),
                 this.namedParams,
diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedParamsNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedParamsNode.java
index ced67544..4f964402 100644
--- a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedParamsNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedParamsNode.java
@@ -3,10 +3,16 @@ package org.shedlang.compiler.ast.untyped;
 import org.shedlang.compiler.sources.Source;
 
 import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public record UntypedParamsNode(
     List<UntypedParamNode> positional,
     List<UntypedParamNode> named,
     Source source
 ) implements UntypedNode {
+    public Iterable<UntypedParamNode> all() {
+        return Stream.concat(positional.stream(), named.stream())
+            .collect(Collectors.toList());
+    }
 }
diff --git a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
index db25ac3b..257aaa18 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
@@ -577,6 +577,12 @@ public class TypeChecker {
         UntypedFunctionDefinitionNode untyped,
         TypeCheckerContext context
     ) {
+        for (var param : untyped.signature().params().all()) {
+            if (param.type().isEmpty()) {
+                throw new FunctionSignatureMissingParamTypeError(param.source());
+            }
+        }
+
         var typedSignature = typeCheckFunctionSignature(untyped.signature(), context);
 
         var type = new FunctionType(
diff --git a/src/main/java/org/shedlang/compiler/typechecker/errors/FunctionSignatureMissingParamTypeError.java b/src/main/java/org/shedlang/compiler/typechecker/errors/FunctionSignatureMissingParamTypeError.java
new file mode 100644
index 00000000..9aef71ec
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/typechecker/errors/FunctionSignatureMissingParamTypeError.java
@@ -0,0 +1,10 @@
+package org.shedlang.compiler.typechecker.errors;
+
+import org.shedlang.compiler.errors.SourceError;
+import org.shedlang.compiler.sources.Source;
+
+public class FunctionSignatureMissingParamTypeError extends SourceError {
+    public FunctionSignatureMissingParamTypeError(Source source) {
+        super("Param is missing param type", source);
+    }
+}