fix: remove nested if/then duplicate serialization (#471)

index.js

@@ -523,8 +523,9 @@ function addIfThenElse (location) {
 
   if (thenSchema.if && thenSchema.then) {
     code += addIfThenElse(thenLocation)
+  } else {
+    code += buildInnerObject(thenLocation)
   }
-  code += buildInnerObject(thenLocation)
   code += `
     }
   `
@@ -538,8 +539,9 @@ function addIfThenElse (location) {
 
   if (elseSchema.if && elseSchema.then) {
     code += addIfThenElse(elseLocation)
+  } else {
+    code += buildInnerObject(elseLocation)
   }
-  code += buildInnerObject(elseLocation)
   code += `
       }
     `
@@ -582,15 +584,13 @@ function buildObject (location) {
       var addComma = false
   `
 
-  let rCode
   if (schema.if && schema.then) {
-    rCode = addIfThenElse(location)
+    functionCode += addIfThenElse(location)
   } else {
-    rCode = buildInnerObject(location)
+    functionCode += buildInnerObject(location)
   }
 
-  // Removes the comma if is the last element of the string (in case there are not properties)
-  functionCode += `${rCode}
+  functionCode += `
       json += '}'
       return json
     }

test/if-then-else.test.js

@@ -333,3 +333,38 @@ t.test('if-then-else', t => {
 
   t.end()
 })
+
+t.test('nested if/then', t => {
+  t.plan(2)
+
+  const schema = {
+    type: 'object',
+    properties: { a: { type: 'string' } },
+    if: {
+      type: 'object',
+      properties: { foo: { type: 'string' } }
+    },
+    then: {
+      properties: { bar: { type: 'string' } },
+      if: {
+        type: 'object',
+        properties: { foo1: { type: 'string' } }
+      },
+      then: {
+        properties: { bar1: { type: 'string' } }
+      }
+    }
+  }
+
+  const stringify = build(schema)
+
+  t.equal(
+    stringify({ a: 'A', foo: 'foo', bar: 'bar' }),
+    JSON.stringify({ a: 'A', bar: 'bar' })
+  )
+
+  t.equal(
+    stringify({ a: 'A', foo: 'foo', bar: 'bar', foo1: 'foo1', bar1: 'bar1' }),
+    JSON.stringify({ a: 'A', bar: 'bar', bar1: 'bar1' })
+  )
+})