auto merge of #8294 : erickt/rust/map-move, r=bblum

According to #7887, we've decided to use the syntax of `fn map<U>(f: &fn(&T) -> U) -> U`, which passes a reference to the closure, and to `fn map_move<U>(f: &fn(T) -> U) -> U` which moves the value into the closure. This PR adds these `.map_move()` functions to `Option` and `Result`.

In addition, it has these other minor features:
 
* Replaces a couple uses of `option.get()`, `result.get()`, and `result.get_err()` with `option.unwrap()`, `result.unwrap()`, and `result.unwrap_err()`. (See #8268 and #8288 for a more thorough adaptation of this functionality.
* Removes `option.take_map()` and `option.take_map_default()`. These two functions can be easily written as `.take().map_move(...)`.
* Adds a better error message to `result.unwrap()` and `result.unwrap_err()`.

Author: bors

src/compiletest/compiletest.rs

@@ -109,8 +109,8 @@ pub fn parse_config(args: ~[~str]) -> config {
         compile_lib_path: getopts::opt_str(matches, "compile-lib-path"),
         run_lib_path: getopts::opt_str(matches, "run-lib-path"),
         rustc_path: opt_path(matches, "rustc-path"),
-        clang_path: getopts::opt_maybe_str(matches, "clang-path").map(|s| Path(*s)),
-        llvm_bin_path: getopts::opt_maybe_str(matches, "llvm-bin-path").map(|s| Path(*s)),
+        clang_path: getopts::opt_maybe_str(matches, "clang-path").map_move(|s| Path(s)),
+        llvm_bin_path: getopts::opt_maybe_str(matches, "llvm-bin-path").map_move(|s| Path(s)),
         src_base: opt_path(matches, "src-base"),
         build_base: opt_path(matches, "build-base"),
         aux_base: opt_path(matches, "aux-base"),
@@ -123,14 +123,14 @@ pub fn parse_config(args: ~[~str]) -> config {
             } else {
                 None
             },
-        logfile: getopts::opt_maybe_str(matches, "logfile").map(|s| Path(*s)),
-        save_metrics: getopts::opt_maybe_str(matches, "save-metrics").map(|s| Path(*s)),
+        logfile: getopts::opt_maybe_str(matches, "logfile").map_move(|s| Path(s)),
+        save_metrics: getopts::opt_maybe_str(matches, "save-metrics").map_move(|s| Path(s)),
         ratchet_metrics:
-            getopts::opt_maybe_str(matches, "ratchet-metrics").map(|s| Path(*s)),
+            getopts::opt_maybe_str(matches, "ratchet-metrics").map_move(|s| Path(s)),
         ratchet_noise_percent:
             getopts::opt_maybe_str(matches,
-                                   "ratchet-noise-percent").map(|s|
-                                                                f64::from_str(*s).unwrap()),
+                                   "ratchet-noise-percent").map_move(|s|
+                                                                     f64::from_str(s).unwrap()),
         runtool: getopts::opt_maybe_str(matches, "runtool"),
         rustcflags: getopts::opt_maybe_str(matches, "rustcflags"),
         jit: getopts::opt_present(matches, "jit"),

src/compiletest/runtest.rs

@@ -162,9 +162,8 @@ fn run_pretty_test(config: &config, props: &TestProps, testfile: &Path) {
         round += 1;
     }
 
-    let mut expected =
-        match props.pp_exact {
-          Some(ref file) => {
+    let mut expected = match props.pp_exact {
+        Some(ref file) => {
             let filepath = testfile.dir_path().push_rel(file);
             io::read_whole_file_str(&filepath).unwrap()
           }