auto merge of rust-lang#78 : huonw/cargo/minor-de-.unwrapping, r=alexcrichton

I don't think any of the `.unwrap`s I touched can actually be hit since they all seem to have checks earlier, but reducing the number of calls is always nice and makes the code easier to verify.

I'm not sure if the `,` -> `:` commit is actually correct, I was just working from the surrounding context.

Author: bors

src/bin/cargo-verify-project.rs

@@ -26,12 +26,13 @@ fn main() {
         }
     };
 
-    if !matches.opt_present("m") {
-        fail("missing-argument", "manifest");
-        return;
-    }
-
-    let manifest = matches.opt_str("m").unwrap();
+    let manifest = match matches.opt_str("m") {
+        Some(m) => m,
+        None => {
+            fail("missing-argument", "manifest");
+            return;
+        }
+    };
     let file = Path::new(manifest);
     let contents = match File::open(&file).read_to_str() {
         Ok(s) => s,
@@ -50,6 +51,6 @@ fn main() {
 }
 
 fn fail(reason: &str, value: &str) {
-    println!(r#"{{ "{:s}", "{:s}" }}"#, reason, value);
+    println!(r#"{{ "{:s}": "{:s}" }}"#, reason, value);
     set_exit_status(1);
 }

src/cargo/core/package.rs

@@ -155,12 +155,13 @@ impl PackageSet {
     }
 
     pub fn pop(&mut self) -> Package {
-        self.packages.pop().unwrap()
+        self.packages.pop().expect("PackageSet.pop: empty set")
     }
 
     /// Get a package by name out of the set
     pub fn get<'a>(&'a self, name: &str) -> &'a Package {
-        self.packages.iter().find(|pkg| name == pkg.get_name()).unwrap()
+        self.packages.iter().find(|pkg| name == pkg.get_name())
+            .expect("PackageSet.get: empty set")
     }
 
     pub fn get_all<'a>(&'a self, names: &[&str]) -> Vec<&'a Package> {

src/cargo/ops/cargo_rustc.rs

@@ -168,9 +168,9 @@ fn compile_custom(pkg: &Package, cmd: &str, cx: &Context) -> CargoResult<()> {
     let mut cmd = cmd.split(' ');
     let mut p = util::process(cmd.next().unwrap())
                      .cwd(pkg.get_root())
-                     .env("OUT_DIR", Some(cx.dest.as_str().unwrap()))
+                     .env("OUT_DIR", Some(cx.dest.as_str().expect("non-UTF8 dest path")))
                      .env("DEPS_DIR", Some(cx.dest.join(cx.deps_dir)
-                                             .as_str().unwrap()));
+                                             .as_str().expect("non-UTF8 deps path")));
     for arg in cmd {
         p = p.arg(arg);
     }

src/cargo/util/config.rs

@@ -1,4 +1,4 @@
-use std::{io,fmt,os};
+use std::{io,fmt,os, result};
 use std::collections::HashMap;
 use serialize::{Encodable,Encoder};
 use toml;
@@ -231,17 +231,15 @@ fn merge_array(existing: &mut ConfigValue, val: &[toml::Value],
     match existing.value {
         String(_) => Err(internal("should be an Array, but it was a String")),
         List(ref mut list) => {
-            let new_list: Vec<CargoResult<String>> =
-                val.iter().map(toml_string).collect();
-            if new_list.iter().any(|v| v.is_err()) {
-                return Err(internal("should be an Array of Strings, but \
-                                     was an Array of other values"));
-            } else {
-                let new_list: Vec<String> =
-                    new_list.move_iter().map(|v| v.unwrap()).collect();
-                list.push_all(new_list.as_slice());
-                existing.path.push(path.clone());
-                Ok(())
+            let r: CargoResult<Vec<String>> = result::collect(val.iter().map(toml_string));
+            match r {
+                Err(_) => Err(internal("should be an Array of Strings, but \
+                                        was an Array of other values")),
+                Ok(new_list) => {
+                    list.push_all(new_list.as_slice());
+                    existing.path.push(path.clone());
+                    Ok(())
+                }
             }
         }
     }