fix: recursive object analysis (fix #118)

examples/vue3/src/components/ComplexParameter.story.vue

@@ -1,6 +1,12 @@
 <script lang="ts" setup>
 import ComplexParameter from './ComplexParameter.vue'
 
+const parent = { name: 'hello' } as { name: string } & Record<string, unknown>
+const child = {} as Record<string, unknown>
+
+parent.child = child
+child.parent = parent
+
 const myParameter = [
   { action: () => { console.log('Hello world!') } },
 ]
@@ -11,6 +17,9 @@ const myParameter = [
     title="ComplexParameter"
     :layout="{type: 'single', iframe: false}"
   >
-    <ComplexParameter :complex-parameter="myParameter" />
+    <ComplexParameter
+      :complex-parameter="myParameter"
+      :recursive-parameter="parent"
+    />
   </Story>
 </template>

examples/vue3/src/components/ComplexParameter.vue

@@ -3,6 +3,7 @@ import { defineProps } from 'vue'
 
 const props = defineProps<{
   complexParameter: Array<{action: () => void}>
+  recursiveParameter: {name: string} & Record<string, unknown>
 }>()
 </script>
 
@@ -13,4 +14,7 @@ const props = defineProps<{
   >
     Custom click
   </div>
+  <div>
+    {{ recursiveParameter.name }}
+  </div>
 </template>

packages/histoire/src/client/app/codegen/serialize-js.ts

@@ -7,6 +7,8 @@ interface Line {
 }
 
 export function serializeJs (value: any): string {
+  const seen = new Set()
+
   if (value === undefined) {
     return 'undefined'
   }
@@ -20,10 +22,10 @@ export function serializeJs (value: any): string {
     return value ? 'true' : 'false'
   }
   if (Array.isArray(value)) {
-    return printLines(arrayToSourceLines(value))
+    return printLines(arrayToSourceLines(value, seen))
   }
   if (typeof value === 'object') {
-    return printLines(objectToSourceLines(value))
+    return printLines(objectToSourceLines(value, seen))
   }
   if (value?.__autoBuildingObject) {
     return value
@@ -38,7 +40,13 @@ function printLines (lines: Line[]) {
   return lines.map(line => '  '.repeat(line.spaces) + line.line).join('\n')
 }
 
-function objectToSourceLines (object, indentCount = 0) {
+function objectToSourceLines (object, seen: Set<unknown>, indentCount = 0) {
+  if (seen.has(object)) {
+    object = {}
+  } else {
+    seen.add(object)
+  }
+
   return createLines(indentCount, lines => {
     lines.push('{')
     lines.push(...createLines(1, lines => {
@@ -50,18 +58,24 @@ function objectToSourceLines (object, indentCount = 0) {
           printedKey = `'${printedKey}'`
         }
 
-        addLinesFromValue(lines, value, `${printedKey}: `, ',')
+        addLinesFromValue(lines, value, `${printedKey}: `, ',', seen)
       }
     }))
     lines.push('}')
   })
 }
 
-function arrayToSourceLines (array: any[], indentCount = 0) {
+function arrayToSourceLines (array: any[], seen: Set<unknown>, indentCount = 0): Array<Line> {
+  if (seen.has(array)) {
+    array = []
+  } else {
+    seen.add(array)
+  }
+
   return createLines(indentCount, lines => {
     const contentLines = createLines(1, lines => {
       for (const value of array) {
-        addLinesFromValue(lines, value, '', ',')
+        addLinesFromValue(lines, value, '', ',', seen)
       }
     })
     if (contentLines.length === 0) {
@@ -78,7 +92,7 @@ function arrayToSourceLines (array: any[], indentCount = 0) {
   })
 }
 
-function createLines (indentCount: number, handler: (lines: any[]) => unknown) {
+function createLines (indentCount: number, handler: (lines: any[]) => unknown): Array<Line> {
   const lines: any[] = []
   handler(lines)
   return lines.map(line => {
@@ -90,13 +104,13 @@ function createLines (indentCount: number, handler: (lines: any[]) => unknown) {
   })
 }
 
-function addLinesFromValue (lines: Line[], value, before, after) {
+function addLinesFromValue (lines: Line[], value, before, after, seen) {
   let result
   if (Array.isArray(value)) {
-    lines.push(...wrap(arrayToSourceLines(value), before, after))
+    lines.push(...wrap(arrayToSourceLines(value, seen), before, after))
     return
   } else if (value && typeof value === 'object') {
-    lines.push(...wrap(objectToSourceLines(value), before, after))
+    lines.push(...wrap(objectToSourceLines(value, seen), before, after))
     return
   } else if (typeof value === 'string') {
     result = value.includes('\'') ? `\`${value}\`` : `'${value}'`

packages/histoire/src/client/app/util/state.ts

@@ -3,22 +3,28 @@ import type { Variant } from '../types'
 
 const isObject = (val) => val !== null && typeof val === 'object'
 
-export function toRawDeep (val) {
+export function toRawDeep (val, seen = new Set()) {
   const unwrappedValue = isRef(val) ? unref(val) : val
 
+  if (seen.has(unwrappedValue)) {
+    return Array.isArray(unwrappedValue) ? [] : {}
+  }
+
+  seen.add(unwrappedValue)
+
   if (!isObject(unwrappedValue)) {
     return unwrappedValue
   }
 
   if (Array.isArray(unwrappedValue)) {
-    return unwrappedValue.map(toRawDeep)
+    return unwrappedValue.map(value => toRawDeep(value, seen))
   }
 
-  return toRawObject(unwrappedValue)
+  return toRawObject(unwrappedValue, seen)
 }
 
-const toRawObject = (obj: Record<any, any>) => Object.keys(obj).reduce((raw, key) => {
-  raw[key] = toRawDeep(obj[key])
+const toRawObject = (obj: Record<any, any>, seen = new Set()) => Object.keys(obj).reduce((raw, key) => {
+  raw[key] = toRawDeep(obj[key], seen)
   return raw
 }, {})