diff --git a/lib/es6/Option.js b/lib/es6/Option.js
index b965c0d7d4..98e8467077 100644
--- a/lib/es6/Option.js
+++ b/lib/es6/Option.js
@@ -99,19 +99,18 @@ function compare(a, b, cmp) {
 
 function all(options) {
   let acc = [];
-  let returnValue;
+  let hasNone = false;
   let index = 0;
-  while (returnValue === undefined && index < options.length) {
+  while (hasNone === false && index < options.length) {
     let value = options[index];
     if (value !== undefined) {
       acc.push(Primitive_option.valFromOption(value));
       index = index + 1 | 0;
     } else {
-      returnValue = Primitive_option.some(undefined);
+      hasNone = true;
     }
   };
-  let match = returnValue;
-  if (match !== undefined) {
+  if (hasNone) {
     return;
   } else {
     return acc;
diff --git a/lib/js/Option.js b/lib/js/Option.js
index 3bf6857601..ffa98d5746 100644
--- a/lib/js/Option.js
+++ b/lib/js/Option.js
@@ -99,19 +99,18 @@ function compare(a, b, cmp) {
 
 function all(options) {
   let acc = [];
-  let returnValue;
+  let hasNone = false;
   let index = 0;
-  while (returnValue === undefined && index < options.length) {
+  while (hasNone === false && index < options.length) {
     let value = options[index];
     if (value !== undefined) {
       acc.push(Primitive_option.valFromOption(value));
       index = index + 1 | 0;
     } else {
-      returnValue = Primitive_option.some(undefined);
+      hasNone = true;
     }
   };
-  let match = returnValue;
-  if (match !== undefined) {
+  if (hasNone) {
     return;
   } else {
     return acc;
diff --git a/runtime/Option.res b/runtime/Option.res
index e60367a25d..6f4cafb477 100644
--- a/runtime/Option.res
+++ b/runtime/Option.res
@@ -107,20 +107,17 @@ let compare = (a, b, cmp) =>
 
 let all = options => {
   let acc = []
-  let returnValue = ref(None)
+  let hasNone = ref(false)
   let index = ref(0)
-  while returnValue.contents == None && index.contents < options->Array.length {
+  while hasNone.contents == false && index.contents < options->Array.length {
     switch options->Array.getUnsafe(index.contents) {
-    | None => returnValue.contents = Some(None)
+    | None => hasNone.contents = true
     | Some(value) =>
       acc->Array.push(value)
       index.contents = index.contents + 1
     }
   }
-  switch returnValue.contents {
-  | Some(_) => None
-  | None => Some(acc)
-  }
+  hasNone.contents ? None : Some(acc)
 }
 
 let all2 = ((a, b)) => {
diff --git a/tests/tests/src/core/Core_ResultTests.mjs b/tests/tests/src/core/Core_ResultTests.mjs
index 1179e2210e..149b1a1d6c 100644
--- a/tests/tests/src/core/Core_ResultTests.mjs
+++ b/tests/tests/src/core/Core_ResultTests.mjs
@@ -84,6 +84,239 @@ Test.run([
   _0: 15
 });
 
+Test.run([
+  [
+    "Core_ResultTests.res",
+    34,
+    20,
+    25
+  ],
+  "all"
+], Result.all([]), eq, {
+  TAG: "Ok",
+  _0: []
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    35,
+    20,
+    25
+  ],
+  "all"
+], Result.all([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Ok",
+    _0: 2
+  },
+  {
+    TAG: "Ok",
+    _0: 3
+  }
+]), eq, {
+  TAG: "Ok",
+  _0: [
+    1,
+    2,
+    3
+  ]
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    36,
+    20,
+    25
+  ],
+  "all"
+], Result.all([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Error",
+    _0: 2
+  }
+]), eq, {
+  TAG: "Error",
+  _0: 2
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    37,
+    20,
+    25
+  ],
+  "all"
+], Result.all2([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Ok",
+    _0: 2
+  }
+]), eq, {
+  TAG: "Ok",
+  _0: [
+    1,
+    2
+  ]
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    38,
+    20,
+    25
+  ],
+  "all"
+], Result.all2([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Error",
+    _0: 2
+  }
+]), eq, {
+  TAG: "Error",
+  _0: 2
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    39,
+    20,
+    25
+  ],
+  "all"
+], Result.all3([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Ok",
+    _0: 2
+  },
+  {
+    TAG: "Ok",
+    _0: 3
+  }
+]), eq, {
+  TAG: "Ok",
+  _0: [
+    1,
+    2,
+    3
+  ]
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    40,
+    20,
+    25
+  ],
+  "all"
+], Result.all3([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Error",
+    _0: 2
+  },
+  {
+    TAG: "Ok",
+    _0: 3
+  }
+]), eq, {
+  TAG: "Error",
+  _0: 2
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    41,
+    20,
+    25
+  ],
+  "all"
+], Result.all4([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Ok",
+    _0: 2
+  },
+  {
+    TAG: "Ok",
+    _0: 3
+  },
+  {
+    TAG: "Ok",
+    _0: 4
+  }
+]), eq, {
+  TAG: "Ok",
+  _0: [
+    1,
+    2,
+    3,
+    4
+  ]
+});
+
+Test.run([
+  [
+    "Core_ResultTests.res",
+    42,
+    20,
+    25
+  ],
+  "all"
+], Result.all4([
+  {
+    TAG: "Ok",
+    _0: 1
+  },
+  {
+    TAG: "Error",
+    _0: 2
+  },
+  {
+    TAG: "Ok",
+    _0: 3
+  },
+  {
+    TAG: "Ok",
+    _0: 4
+  }
+]), eq, {
+  TAG: "Error",
+  _0: 2
+});
+
 export {
   eq,
   forEachIfOkCallFunction,