Finished migrating parser to be object orientation free. All tests pass

app/imports/parser/parseTree/unaryOperator.js

@@ -0,0 +1,46 @@
+import resolve, { toString, traverse } from '../resolve.js';
+import constant from './constant.js';
+
+const unaryOperator = {
+  create({operator, right}) {
+    return {
+      parseType: 'unaryOperator',
+      operator,
+      right,
+    };
+  },
+  resolve(fn, node, scope, context){
+    const {result: rightNode} = resolve(fn, node.right, scope, context);
+    if (rightNode.parseType !== 'number'){
+      return {
+        result: unaryOperator.create({
+          operator: node.operator,
+          right: rightNode,
+        }),
+        context,
+      };
+    }
+    let right = rightNode.value;
+    let result;
+    switch(node.operator){
+      case '-': result = -right; break;
+      case '+': result = +right; break;
+    }
+    return {
+      result: constant.create({
+        value: result,
+        parseType: typeof result,
+      }),
+      context,
+    };
+  },
+  toString(node){
+    return `${node.operator}${toString(node.right)}`;
+  },
+  traverse(node, fn){
+    fn(node);
+    traverse(node.right, fn);
+  },
+};
+
+export default unaryOperator;