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[refs]

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@@ -5,7 +5,7 @@ refs/heads/snap-stage3: 78a7676898d9f80ab540c6df5d4c9ce35bb50463
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refs/heads/try: 519addf6277dbafccbb4159db4b710c37eaa2ec5
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refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
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refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
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refs/heads/try2: ec2b8c59a7bdbe05b99a7a8470e04c18f20c1958
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refs/heads/try2: e65a8b88cac97bdc01ee01a099915d861406edd6
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refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
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refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
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refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/try2/doc/guide-ffi.md

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@@ -249,6 +249,143 @@ fn main() {
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}
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~~~~
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# Callbacks from C code to Rust functions
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Some external libraries require the usage of callbacks to report back their
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current state or intermediate data to the caller.
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It is possible to pass functions defined in Rust to an external library.
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The requirement for this is that the callback function is marked as `extern`
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with the correct calling convention to make it callable from C code.
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The callback function that can then be sent to through a registration call
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to the C library and afterwards be invoked from there.
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A basic example is:
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Rust code:
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~~~~ {.xfail-test}
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extern fn callback(a:i32) {
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println!("I'm called from C with value {0}", a);
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}
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#[link(name = "extlib")]
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extern {
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fn register_callback(cb: extern "C" fn(i32)) -> i32;
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fn trigger_callback();
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}
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fn main() {
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unsafe {
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register_callback(callback);
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trigger_callback(); // Triggers the callback
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}
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}
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~~~~
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C code:
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~~~~ {.xfail-test}
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typedef void (*rust_callback)(int32_t);
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rust_callback cb;
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int32_t register_callback(rust_callback callback) {
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cb = callback;
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return 1;
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}
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void trigger_callback() {
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cb(7); // Will call callback(7) in Rust
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}
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~~~~
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In this example will Rust's `main()` will call `do_callback()` in C,
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which would call back to `callback()` in Rust.
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## Targetting callbacks to Rust objects
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The former example showed how a global function can be called from C-Code.
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However it is often desired that the callback is targetted to a special
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Rust object. This could be the object that represents the wrapper for the
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respective C object.
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This can be achieved by passing an unsafe pointer to the object down to the
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C library. The C library can then include the pointer to the Rust object in
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the notification. This will provide a unsafe possibility to access the
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referenced Rust object in callback.
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Rust code:
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~~~~ {.xfail-test}
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struct RustObject {
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a: i32,
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// other members
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}
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extern fn callback(target: *RustObject, a:i32) {
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println!("I'm called from C with value {0}", a);
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(*target).a = a; // Update the value in RustObject with the value received from the callback
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}
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#[link(name = "extlib")]
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extern {
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fn register_callback(target: *RustObject, cb: extern "C" fn(*RustObject, i32)) -> i32;
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fn trigger_callback();
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}
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fn main() {
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// Create the object that will be referenced in the callback
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let rust_object = ~RustObject{a: 5, ...};
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unsafe {
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// Gets a raw pointer to the object
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let target_addr:*RustObject = ptr::to_unsafe_ptr(rust_object);
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register_callback(target_addr, callback);
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trigger_callback(); // Triggers the callback
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}
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}
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~~~~
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C code:
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~~~~ {.xfail-test}
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typedef void (*rust_callback)(int32_t);
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void* cb_target;
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rust_callback cb;
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int32_t register_callback(void* callback_target, rust_callback callback) {
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cb_target = callback_target;
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cb = callback;
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return 1;
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}
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void trigger_callback() {
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cb(cb_target, 7); // Will call callback(&rustObject, 7) in Rust
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}
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~~~~
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## Asynchronous callbacks
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In the already given examples the callbacks are invoked as a direct reaction
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to a function call to the external C library.
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The control over the current thread switched from Rust to C to Rust for the
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execution of the callback, but in the end the callback is executed on the
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same thread (and Rust task) that lead called the function which triggered
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the callback.
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Things get more complicated when the external library spawns it's own threads
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and invokes callbacks from there.
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In these cases access to Rust data structures inside he callbacks is
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especially unsafe and proper synchronization mechanisms must be used.
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Besides classical synchronization mechanisms like mutexes one possibility in
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Rust is to use channels (in `std::comm`) to forward data from the C thread
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that invoked the callback into a Rust task.
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If an asychronous callback targets a special object in the Rust address space
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it is also absolutely necessary that no more callbacks are performed by the
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C library after the respective Rust object get's destroyed.
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This can be achieved by unregistering the callback it the object's
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destructor and designing the library in a way that guarantees that no
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callback will be performed after unregistration.
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# Linking
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The `link` attribute on `extern` blocks provides the basic building block for

branches/try2/doc/guide-testing.md

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@@ -33,7 +33,7 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured
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# Unit testing in Rust
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Rust has built in support for simple unit testing. Functions can be
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marked as unit tests using the 'test' attribute.
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marked as unit tests using the `test` attribute.
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~~~
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#[test]
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A test function's signature must have no arguments and no return
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value. To run the tests in a crate, it must be compiled with the
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'--test' flag: `rustc myprogram.rs --test -o myprogram-tests`. Running
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`--test` flag: `rustc myprogram.rs --test -o myprogram-tests`. Running
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the resulting executable will run all the tests in the crate. A test
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is considered successful if its function returns; if the task running
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the test fails, through a call to `fail!`, a failed `check` or
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`assert`, or some other (`assert_eq`, ...) means, then the test fails.
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When compiling a crate with the '--test' flag '--cfg test' is also
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When compiling a crate with the `--test` flag `--cfg test` is also
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implied, so that tests can be conditionally compiled.
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~~~
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~~~
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Additionally `#[test]` items behave as if they also have the
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`#[cfg(test)]` attribute, and will not be compiled when the --test flag
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`#[cfg(test)]` attribute, and will not be compiled when the `--test` flag
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is not used.
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70-
Tests that should not be run can be annotated with the 'ignore'
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Tests that should not be run can be annotated with the `ignore`
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attribute. The existence of these tests will be noted in the test
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runner output, but the test will not be run. Tests can also be ignored
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by configuration so, for example, to ignore a test on windows you can
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write `#[ignore(cfg(target_os = "win32"))]`.
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Tests that are intended to fail can be annotated with the
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'should_fail' attribute. The test will be run, and if it causes its
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`should_fail` attribute. The test will be run, and if it causes its
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task to fail then the test will be counted as successful; otherwise it
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will be counted as a failure. For example:
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}
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~~~
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A test runner built with the '--test' flag supports a limited set of
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A test runner built with the `--test` flag supports a limited set of
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arguments to control which tests are run: the first free argument
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passed to a test runner specifies a filter used to narrow down the set
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of tests being run; the '--ignored' flag tells the test runner to run
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only tests with the 'ignore' attribute.
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of tests being run; the `--ignored` flag tells the test runner to run
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only tests with the `ignore` attribute.
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## Parallelism
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branches/try2/src/compiletest/runtest.rs

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@@ -206,7 +206,8 @@ fn run_pretty_test(config: &config, props: &TestProps, testfile: &Path) {
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}
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fn make_pp_args(config: &config, _testfile: &Path) -> ProcArgs {
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let args = ~[~"-", ~"--pretty", ~"normal"];
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let args = ~[~"-", ~"--pretty", ~"normal",
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~"--target=" + config.target];
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// FIXME (#9639): This needs to handle non-utf8 paths
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return ProcArgs {prog: config.rustc_path.as_str().unwrap().to_owned(), args: args};
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}
@@ -237,9 +238,15 @@ actual:\n\
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fn make_typecheck_args(config: &config, props: &TestProps, testfile: &Path) -> ProcArgs {
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let aux_dir = aux_output_dir_name(config, testfile);
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let target = if props.force_host {
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config.host.as_slice()
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} else {
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config.target.as_slice()
245+
};
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// FIXME (#9639): This needs to handle non-utf8 paths
241247
let mut args = ~[~"-",
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~"--no-trans", ~"--lib",
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~"--target=" + target,
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~"-L", config.build_base.as_str().unwrap().to_owned(),
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~"-L",
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aux_dir.as_str().unwrap().to_owned()];

branches/try2/src/libextra/base64.rs

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@@ -237,8 +237,9 @@ impl<'a> FromBase64 for &'a str {
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}
238238

239239
for (idx, byte) in it {
240-
if (byte as char) != '=' {
241-
return Err(InvalidBase64Character(self.char_at(idx), idx));
240+
match byte as char {
241+
'='|'\r'|'\n' => continue,
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_ => return Err(InvalidBase64Character(self.char_at(idx), idx)),
242243
}
243244
}
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@@ -310,6 +311,8 @@ mod test {
310311
fn test_from_base64_newlines() {
311312
assert_eq!("Zm9v\r\nYmFy".from_base64().unwrap(),
312313
"foobar".as_bytes().to_owned());
314+
assert_eq!("Zm9vYg==\r\n".from_base64().unwrap(),
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"foob".as_bytes().to_owned());
313316
}
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#[test]

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