From b026c0e4c07502b5a88677bc903c0c73314106ac Mon Sep 17 00:00:00 2001
From: Dan Fabulich <dan.fabulich@redfin.com>
Date: Mon, 27 Jun 2016 22:29:11 -0700
Subject: [PATCH 1/3] fs: make existsSync faster by not throwing

The existing implementation throws ignored exceptions, which is slow.
The new implementation returns a simple boolean without throwing.
---
 lib/fs.js        |  8 +++-----
 src/node_file.cc | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/lib/fs.js b/lib/fs.js
index 2fc22b1bddecc0..c6dc8f7759c509 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -259,13 +259,11 @@ fs.exists = function(path, callback) {
 };
 
 fs.existsSync = function(path) {
-  try {
-    nullCheck(path);
-    binding.stat(pathModule._makeLong(path));
-    return true;
-  } catch (e) {
+  if (String(path).indexOf('\u0000') !== -1) {
     return false;
   }
+
+  return binding.accessibleSync(pathModule._makeLong(path), fs.F_OK);
 };
 
 fs.readFile = function(path, options, callback_) {
diff --git a/src/node_file.cc b/src/node_file.cc
index 77d11756a2dbe5..3002b1a03ed9ae 100644
--- a/src/node_file.cc
+++ b/src/node_file.cc
@@ -27,6 +27,7 @@
 namespace node {
 
 using v8::Array;
+using v8::Boolean;
 using v8::Context;
 using v8::EscapableHandleScope;
 using v8::Function;
@@ -399,6 +400,30 @@ static void Access(const FunctionCallbackInfo<Value>& args) {
   }
 }
 
+static void AccessibleSync(const FunctionCallbackInfo<Value>& args) {
+  Environment* env = Environment::GetCurrent(args.GetIsolate());
+  HandleScope scope(env->isolate());
+
+  if (args.Length() < 2)
+    return TYPE_ERROR("path and mode are required");
+  if (!args[1]->IsInt32())
+    return TYPE_ERROR("mode must be an integer");
+
+  BufferValue path(env->isolate(), args[0]);
+  ASSERT_PATH(path)
+
+  int mode = static_cast<int>(args[1]->Int32Value());
+
+  fs_req_wrap req_wrap;
+  env->PrintSyncTrace();
+  int err = uv_fs_access(
+    env->event_loop(), &req_wrap.req, *path, mode, nullptr);
+
+  bool failed = err < 0;
+
+  args.GetReturnValue().Set(Boolean::New(env->isolate(), !failed));
+}
+
 
 static void Close(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
@@ -1448,6 +1473,7 @@ void InitFs(Local<Object> target,
               env->NewFunctionTemplate(FSInitialize)->GetFunction());
 
   env->SetMethod(target, "access", Access);
+  env->SetMethod(target, "accessibleSync", AccessibleSync);
   env->SetMethod(target, "close", Close);
   env->SetMethod(target, "open", Open);
   env->SetMethod(target, "read", Read);

From 19689e4369ef2a1faf388ed3add59d8fb1a98e85 Mon Sep 17 00:00:00 2001
From: Dan Fabulich <dan.fabulich@redfin.com>
Date: Mon, 27 Jun 2016 22:30:37 -0700
Subject: [PATCH 2/3] fs: make exists faster by using access

access is faster than stat, because we don't have to return the
actual stat results.
---
 lib/fs.js | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/lib/fs.js b/lib/fs.js
index c6dc8f7759c509..0c75f4d6b1de1b 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -250,10 +250,8 @@ fs.accessSync = function(path, mode) {
 
 fs.exists = function(path, callback) {
   if (!nullCheck(path, cb)) return;
-  var req = new FSReqWrap();
-  req.oncomplete = cb;
-  binding.stat(pathModule._makeLong(path), req);
-  function cb(err, stats) {
+  fs.access(path, fs.F_OK, cb);
+  function cb(err) {
     if (callback) callback(err ? false : true);
   }
 };

From d255e0fe6960dc6ae8401de13dc9898f9167c080 Mon Sep 17 00:00:00 2001
From: Dan Fabulich <dan.fabulich@redfin.com>
Date: Mon, 27 Jun 2016 22:31:20 -0700
Subject: [PATCH 3/3] fs: undeprecate existsSync

There's no alternative method to use that doesn't throw an exception
when the file doesn't exist.
---
 doc/api/fs.md | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/doc/api/fs.md b/doc/api/fs.md
index 40b8a990631271..3cac285dec7903 100644
--- a/doc/api/fs.md
+++ b/doc/api/fs.md
@@ -597,8 +597,9 @@ deprecated: v1.0.0
 * `path` {String | Buffer}
 * `callback` {Function}
 
-Test whether or not the given path exists by checking with the file system.
-Then call the `callback` argument with either true or false.  Example:
+Test whether or not the given path exists and is accessible by checking
+with the file system. Then call the `callback` argument with either
+true or false.  Example:
 
 ```js
 fs.exists('/etc/passwd', (exists) => {
@@ -615,16 +616,12 @@ non-existent.
 ## fs.existsSync(path)
 <!-- YAML
 added: v0.1.21
-deprecated: v1.0.0
 -->
 
-> Stability: 0 - Deprecated: Use [`fs.statSync()`][] or [`fs.accessSync()`][]
-> instead.
-
 * `path` {String | Buffer}
 
 Synchronous version of [`fs.exists()`][].
-Returns `true` if the file exists, `false` otherwise.
+Returns `true` if the file exists and is accessible, `false` otherwise.
 
 ## fs.fchmod(fd, mode, callback)
 <!-- YAML