From 351b8f7c37d45f689529c213f3cac6553c9a568a Mon Sep 17 00:00:00 2001
From: Sergio Benitez <sb@sergio.bz>
Date: Sat, 7 Jul 2018 18:51:26 -0700
Subject: [PATCH] Small fixes to request-local state cache implementation.

---
 Cargo.toml                                    |  2 +-
 core/lib/src/request/request.rs               | 24 +++++++++----------
 .../Cargo.toml                                |  2 +-
 .../src/main.rs                               |  1 +
 .../src/tests.rs                              |  3 +--
 5 files changed, 15 insertions(+), 17 deletions(-)
 rename examples/{request_state_local_cache => request_local_state}/Cargo.toml (82%)
 rename examples/{request_state_local_cache => request_local_state}/src/main.rs (99%)
 rename examples/{request_state_local_cache => request_local_state}/src/tests.rs (91%)

diff --git a/Cargo.toml b/Cargo.toml
index bd003e43..74475d03 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,7 +22,7 @@ members = [
   "examples/content_types",
   "examples/ranking",
   "examples/testing",
-  "examples/request_state_local_cache",
+  "examples/request_local_state",
   "examples/request_guard",
   "examples/stream",
   "examples/json",
diff --git a/core/lib/src/request/request.rs b/core/lib/src/request/request.rs
index e93a90f2..c362a73d 100644
--- a/core/lib/src/request/request.rs
+++ b/core/lib/src/request/request.rs
@@ -82,8 +82,8 @@ impl<'r> Request<'r> {
     }
 
     /// Retrieves the cached value for type `T` from the request-local cached
-    /// state of `self`. If no such value has previously been cached for
-    /// this request, `f` is called to produce the value which is subsequently
+    /// state of `self`. If no such value has previously been cached for this
+    /// request, `f` is called to produce the value which is subsequently
     /// returned.
     ///
     /// # Example
@@ -92,26 +92,24 @@ impl<'r> Request<'r> {
     /// # use rocket::http::Method;
     /// # use rocket::Request;
     /// # struct User;
-    /// fn current_user() -> User {
-    ///     // Load user...
+    /// fn current_user(request: &Request) -> User {
+    ///     // Validate request for a given user, load from database, etc.
     ///     # User
     /// }
     ///
     /// # Request::example(Method::Get, "/uri", |request| {
-    /// let user = request.local_cache(current_user);
+    /// let user = request.local_cache(|| current_user(request));
     /// # });
     /// ```
     pub fn local_cache<T, F>(&self, f: F) -> &T
-        where T: Send + Sync + 'static,
-              F: FnOnce() -> T {
-
-        match self.state.cache.try_get() {
-            Some(cached) => cached,
-            None => {
+        where F: FnOnce() -> T,
+              T: Send + Sync + 'static
+    {
+        self.state.cache.try_get()
+            .unwrap_or_else(|| {
                 self.state.cache.set(f());
                 self.state.cache.get()
-            }
-        }
+            })
     }
 
     /// Retrieve the method from `self`.
diff --git a/examples/request_state_local_cache/Cargo.toml b/examples/request_local_state/Cargo.toml
similarity index 82%
rename from examples/request_state_local_cache/Cargo.toml
rename to examples/request_local_state/Cargo.toml
index 0c720023..0de3d204 100644
--- a/examples/request_state_local_cache/Cargo.toml
+++ b/examples/request_local_state/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "request_state_local_cache"
+name = "request_local_state"
 version = "0.0.0"
 workspace = "../../"
 publish = false
diff --git a/examples/request_state_local_cache/src/main.rs b/examples/request_local_state/src/main.rs
similarity index 99%
rename from examples/request_state_local_cache/src/main.rs
rename to examples/request_local_state/src/main.rs
index c51cefa1..8d90f2e7 100644
--- a/examples/request_state_local_cache/src/main.rs
+++ b/examples/request_local_state/src/main.rs
@@ -1,5 +1,6 @@
 #![feature(plugin, decl_macro)]
 #![plugin(rocket_codegen)]
+
 extern crate rocket;
 
 use std::sync::atomic::{AtomicUsize, Ordering};
diff --git a/examples/request_state_local_cache/src/tests.rs b/examples/request_local_state/src/tests.rs
similarity index 91%
rename from examples/request_state_local_cache/src/tests.rs
rename to examples/request_local_state/src/tests.rs
index 1e16f7d8..602b1694 100644
--- a/examples/request_state_local_cache/src/tests.rs
+++ b/examples/request_local_state/src/tests.rs
@@ -1,7 +1,6 @@
 use std::sync::atomic::{Ordering};
 
-use ::Atomics;
-use super::rocket;
+use super::{rocket, Atomics};
 use rocket::local::Client;
 
 #[test]