Fix if/else type checking and recursion test

src/abstract_tree/function_call.rs

@@ -37,18 +37,18 @@ impl AbstractTree for FunctionCall {
         }
     }
 
-    fn run(self, _context: &Context) -> Result<Action, RuntimeError> {
+    fn run(self, context: &Context) -> Result<Action, RuntimeError> {
-        let value = self.function.run(_context)?.as_value()?;
+        let value = self.function.run(context)?.as_value()?;
         let function = value.as_function()?;
         let mut arguments = Vec::with_capacity(self.arguments.len());
 
         for expression in self.arguments {
-            let value = expression.run(_context)?.as_value()?;
+            let value = expression.run(context)?.as_value()?;
 
             arguments.push(value);
         }
 
-        let function_context = Context::new();
+        let function_context = Context::with_data_from(context)?;
 
         function.call(arguments, function_context)
     }

src/abstract_tree/if_else.rs

@@ -24,11 +24,18 @@ impl IfElse {
 
 impl AbstractTree for IfElse {
     fn expected_type(&self, _context: &Context) -> Result<Type, ValidationError> {
-        Ok(Type::None)
+        self.if_block.expected_type(_context)
+    }
+
+    fn validate(&self, context: &Context) -> Result<(), ValidationError> {
+        if let Type::Boolean = self.if_expression.expected_type(context)? {
+            if let Some(else_block) = &self.else_block {
+                let expected = self.if_block.expected_type(context)?;
+                let actual = else_block.expected_type(context)?;
+
+                expected.check(&actual)?;
             }
 
-    fn validate(&self, _context: &Context) -> Result<(), ValidationError> {
-        if let Type::Boolean = self.if_expression.expected_type(_context)? {
             Ok(())
         } else {
             Err(ValidationError::ExpectedBoolean)

src/abstract_tree/value_node.rs

@@ -78,7 +78,7 @@ impl AbstractTree for ValueNode {
             body,
         } = self
         {
-            let function_context = Context::new();
+            let function_context = Context::with_types_from(context)?;
 
             for (identifier, r#type) in parameters {
                 function_context.set_type(identifier.clone(), r#type.clone())?;

src/context.rs

@@ -33,6 +33,28 @@ impl Context {
         }
     }
 
+    pub fn with_types_from(other: &Context) -> Result<Self, RwLockPoisonError> {
+        let mut new_data = BTreeMap::new();
+
+        for (identifier, value_data) in other.inner.read()?.iter() {
+            if let ValueData::Type(_) = value_data {
+                new_data.insert(identifier.clone(), value_data.clone());
+            }
+        }
+
+        Ok(Self::with_data(new_data))
+    }
+
+    pub fn with_data_from(other: &Context) -> Result<Self, RwLockPoisonError> {
+        let mut new_data = BTreeMap::new();
+
+        for (identifier, value_data) in other.inner.read()?.iter() {
+            new_data.insert(identifier.clone(), value_data.clone());
+        }
+
+        Ok(Self::with_data(new_data))
+    }
+
     pub fn get_data(
         &self,
         identifier: &Identifier,