Fix undefined if

src/exec.js

@@ -547,6 +547,7 @@ function execFor(ctx, ast) {
     let v = exec(ctx, ast.condition);
     if (ctx.error) return;
 
+    if (typeof v.value != "undefined") {
         while ((v.value.neq(0))&&(!ctx.returnValue)) {
             exec(ctx, ast.body);
             if (ctx.error) return;
@@ -557,12 +558,14 @@ function execFor(ctx, ast) {
             v = exec(ctx, ast.condition);
             if (ctx.error) return;
         }
+    }
 }
 
 function execWhile(ctx, ast) {
     let v = exec(ctx, ast.condition);
     if (ctx.error) return;
 
+    if (typeof v.value != "undefined") {
         while ((v.value.neq(0))&&(!ctx.returnValue)) {
             exec(ctx, ast.body);
             if (ctx.error) return;
@@ -570,12 +573,14 @@ function execWhile(ctx, ast) {
             v = exec(ctx, ast.condition);
             if (ctx.error) return;
         }
+    }
 }
 
 function execIf(ctx, ast) {
     let v = exec(ctx, ast.condition);
     if (ctx.error) return;
 
+    if (typeof v.value != "undefined") {
         if ((v.value.neq(0))&&(!ctx.returnValue)) {
             exec(ctx, ast.then);
             if (ctx.error) return;
@@ -585,6 +590,7 @@ function execIf(ctx, ast) {
                 if (ctx.error) return;
             }
         }
+    }
 }
 
 

test/cases.js

@@ -0,0 +1,14 @@
+const chai = require("chai");
+const path = require("path");
+const snarkjs = require("snarkjs");
+const crypto = require("crypto");
+
+const compiler = require("../index.js");
+
+const assert = chai.assert;
+
+describe("Sum test", () => {
+    it("Should compile a code with an undefined if", async() => {
+        await compiler(path.join(__dirname, "circuits", "undefinedif.circom"));
+    });
+});

test/circuits/undefinedif.circom

@@ -0,0 +1,14 @@
+template X() {
+    signal input i;
+    signal input j;
+    signal output out;
+
+    if (i == 0) {
+        out <-- i;
+    }
+    else {
+        out <-- j;
+    }
+}
+
+component main = X();