From 9db7fdf0e5797f38605bc37a2f916a06c699c10a Mon Sep 17 00:00:00 2001
From: jos <wjosdejong@gmail.com>
Date: Sun, 17 Dec 2017 21:10:07 +0100
Subject: [PATCH] Fixed keeping id's intact when replacing a value

---
 src/patchEson.js       | 11 ++++++++++-
 test/patchEson.test.js | 29 ++++++++++++++---------------
 2 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/src/patchEson.js b/src/patchEson.js
index 2ab27cf..f004f35 100644
--- a/src/patchEson.js
+++ b/src/patchEson.js
@@ -135,8 +135,17 @@ export function patchEson (eson, patch, expand = expandAll) {
 export function replace (data, path, value) {
   const oldValue = getIn(data, path)
 
+  // keep the original id
+  let newValue = value
+  newValue = setIn(newValue, [META, 'id'], oldValue[META].id)
+
+  // FIXME: get the original expanded state of the copied value from JSON-Patch
+  if (newValue[META].type === 'Object' || newValue[META].type === 'Array') {
+    newValue = setIn(newValue, [META, 'expanded'], true)
+  }
+
   return {
-    data: setIn(data, path, value),
+    data: setIn(data, path, newValue),
     revert: [{
       op: 'replace',
       path: compileJSONPointer(path),
diff --git a/test/patchEson.test.js b/test/patchEson.test.js
index 09a7a4d..b27dff1 100644
--- a/test/patchEson.test.js
+++ b/test/patchEson.test.js
@@ -153,21 +153,20 @@ test('jsonpatch replace', t => {
   ])
 })
 
-// // FIXME: keep ids intact
-// test('jsonpatch replace (keep ids intact)', t => {
-//   const json = { value: 42 }
-//   const patch = [
-//     {op: 'replace', path: '/value', value: 100}
-//   ]
-//
-//   const data = jsonToEson(json)
-//   const valueId = data.value[META].id
-//
-//   const patchedData = patchEson(data, patch).data
-//   const patchedValueId = patchedData.value[META].id
-//
-//   t.is(patchedValueId, valueId)
-// })
+test('jsonpatch replace (keep ids intact)', t => {
+  const json = { value: 42 }
+  const patch = [
+    {op: 'replace', path: '/value', value: 100}
+  ]
+
+  const data = jsonToEson(json)
+  const valueId = data.value[META].id
+
+  const patchedData = patchEson(data, patch).data
+  const patchedValueId = patchedData.value[META].id
+
+  t.is(patchedValueId, valueId)
+})
 
 test('jsonpatch copy', t => {
   const json = {