From 4df6da4aa01314f31ea87a951b5c5cd3d5ef9242 Mon Sep 17 00:00:00 2001
From: Brian Koropoff <bkoropoff@gmail.com>
Date: Sun, 5 Oct 2014 15:59:58 -0700
Subject: [PATCH] Clean up some uses of `Option::map` only for its side effects

---
 src/cargo/core/resolver.rs               |  6 +++---
 src/cargo/lib.rs                         | 22 ++++++++++++----------
 src/cargo/ops/cargo_generate_lockfile.rs |  8 ++++----
 src/cargo/util/errors.rs                 |  4 +++-
 4 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/src/cargo/core/resolver.rs b/src/cargo/core/resolver.rs
index 278fde481..2d4b4d174 100644
--- a/src/cargo/core/resolver.rs
+++ b/src/cargo/core/resolver.rs
@@ -97,9 +97,9 @@ pub struct EncodablePackageId {
 impl<E, S: Encoder<E>> Encodable<S, E> for EncodablePackageId {
     fn encode(&self, s: &mut S) -> Result<(), E> {
         let mut out = format!("{} {}", self.name, self.version);
-        self.source.as_ref().map(|s| {
-            out.push_str(format!(" ({})", s.to_url()).as_slice())
-        });
+        if let Some(ref s) = self.source {
+            out.push_str(format!(" ({})", s.to_url()).as_slice());
+        }
         out.encode(s)
     }
 }
diff --git a/src/cargo/lib.rs b/src/cargo/lib.rs
index 87a495aff..1ca101c91 100644
--- a/src/cargo/lib.rs
+++ b/src/cargo/lib.rs
@@ -3,6 +3,7 @@
 
 #![feature(macro_rules, phase)]
 #![feature(default_type_params)]
+#![feature(if_let)]
 #![deny(bad_style)]
 
 extern crate libc;
@@ -143,12 +144,11 @@ pub fn process_executed<'a,
                             shell: &mut MultiShell) {
     match result {
         Err(e) => handle_error(e, shell),
-        Ok(encodable) => {
-            encodable.map(|encodable| {
-                let encoded = json::encode(&encodable);
-                println!("{}", encoded);
-            });
+        Ok(Some(encodable)) => {
+            let encoded = json::encode(&encodable);
+            println!("{}", encoded);
         }
+        _ => {}
     }
 }
 
@@ -189,12 +189,12 @@ pub fn handle_error(err: CliError, shell: &mut MultiShell) {
         if unknown {
             let _ = shell.error(error.to_string());
         }
-        error.detail().map(|detail| {
+        if let Some(detail) = error.detail() {
             let _ = shell.err().say(format!("{}", detail), BLACK);
-        });
-        error.cause().map(|err| {
+        }
+        if let Some(err) = error.cause() {
             let _ = handle_cause(err, shell);
-        });
+        }
         Ok(())
       });
 
@@ -205,7 +205,9 @@ fn handle_cause(err: &CargoError, shell: &mut MultiShell) {
     let _ = shell.err().say("\nCaused by:", BLACK);
     let _ = shell.err().say(format!("  {}", err.description()), BLACK);
 
-    err.cause().map(|e| handle_cause(e, shell));
+    if let Some(e) = err.cause() {
+        handle_cause(e, shell)
+    }
 }
 
 pub fn version() -> String {
diff --git a/src/cargo/ops/cargo_generate_lockfile.rs b/src/cargo/ops/cargo_generate_lockfile.rs
index f9cde510c..10095a69d 100644
--- a/src/cargo/ops/cargo_generate_lockfile.rs
+++ b/src/cargo/ops/cargo_generate_lockfile.rs
@@ -153,11 +153,11 @@ fn emit_package(dep: &toml::TomlTable, out: &mut String) {
     out.push_str(format!("name = {}\n", lookup(dep, "name")).as_slice());
     out.push_str(format!("version = {}\n", lookup(dep, "version")).as_slice());
 
-    dep.find(&"source".to_string()).map(|_| {
+    if dep.contains_key(&"source".to_string()) {
         out.push_str(format!("source = {}\n", lookup(dep, "source")).as_slice());
-    });
+    }
 
-    dep.find(&"dependencies".to_string()).map(|s| {
+    if let Some(ref s) = dep.find(&"dependencies".to_string()) {
         let slice = s.as_slice().unwrap();
 
         if !slice.is_empty() {
@@ -170,7 +170,7 @@ fn emit_package(dep: &toml::TomlTable, out: &mut String) {
             out.push_str("]\n");
         }
         out.push_str("\n");
-    });
+    }
 }
 
 fn lookup<'a>(table: &'a toml::TomlTable, key: &str) -> &'a toml::Value {
diff --git a/src/cargo/util/errors.rs b/src/cargo/util/errors.rs
index 594ea8ad9..3653a491d 100644
--- a/src/cargo/util/errors.rs
+++ b/src/cargo/util/errors.rs
@@ -179,7 +179,9 @@ impl Show for ProcessError {
             None => "never executed".to_string()
         };
         try!(write!(f, "{} (status={})", self.msg, exit));
-        self.output().map(|out| { let _ = write!(f, "{}", out); });
+        if let Some(out) = self.output() {
+            try!(write!(f, "{}", out));
+        }
         Ok(())
     }
 }
-- 
2.30.2