Auto merge of #23676 - servo:check, r=Manishearth

Share more `./mach build` logic with mach check, doc, test-unit

Fixes #23659

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---
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32 files changed, 272 insertions, 306 deletions

diff --git a/components/canvas/Cargo.toml b/components/canvas/Cargo.toml
index 6e6fb2b0a76..906fa84b434 100644
--- a/components/canvas/Cargo.toml
+++ b/components/canvas/Cargo.toml
@@ -11,10 +11,10 @@ name = "canvas"
 path = "lib.rs"
 
 [features]
-azure_backend = ["azure"]
-default = ["azure_backend"]
+canvas2d-azure = ["azure"]
+canvas2d-raqote = ["raqote"]
+default = ["canvas2d-azure"]
 webgl_backtrace = ["canvas_traits/webgl_backtrace"]
-raqote_backend = ["raqote"]
 no_wgl = ["offscreen_gl_context/no_wgl"]
 
 [dependencies]
diff --git a/components/canvas/build.rs b/components/canvas/build.rs
new file mode 100644
index 00000000000..17010bce69d
--- /dev/null
+++ b/components/canvas/build.rs
@@ -0,0 +1,20 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+fn main() {
+    let azure = std::env::var_os("CARGO_FEATURE_CANVAS2D_AZURE").is_some();
+    let raqote = std::env::var_os("CARGO_FEATURE_CANVAS2D_RAQOTE").is_some();
+
+    if !(azure || raqote) {
+        error("Must enable one of the `canvas2d-azure` or `canvas2d-raqote` features.")
+    }
+    if azure && raqote {
+        error("Must not enable both of the `canvas2d-azure` and `canvas2d-raqote` features.")
+    }
+}
+
+fn error(message: &str) {
+    print!("\n\n    Error: {}\n\n", message);
+    std::process::exit(1)
+}
diff --git a/components/canvas/canvas_data.rs b/components/canvas/canvas_data.rs
index 79adbee7df8..aa6539ebbb9 100644
--- a/components/canvas/canvas_data.rs
+++ b/components/canvas/canvas_data.rs
@@ -281,92 +281,92 @@ pub trait GenericDrawTarget {
 
 #[derive(Clone)]
 pub enum ExtendMode {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::ExtendMode),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 pub enum GradientStop {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::AzGradientStop),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 pub enum GradientStops {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::GradientStops),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 #[derive(Clone)]
 pub enum Color {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::Color),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 #[derive(Clone)]
 pub enum CompositionOp {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::CompositionOp),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 pub enum SurfaceFormat {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::SurfaceFormat),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 #[derive(Clone)]
 pub enum SourceSurface {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::SourceSurface),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 pub enum Path {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::Path),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 #[derive(Clone)]
 pub enum Pattern {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::Pattern),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 pub enum DrawSurfaceOptions {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::DrawSurfaceOptions),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 #[derive(Clone)]
 pub enum DrawOptions {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::DrawOptions),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(()),
 }
 
 #[derive(Clone)]
 pub enum StrokeOptions<'a> {
-    #[cfg(feature = "azure_backend")]
+    #[cfg(feature = "canvas2d-azure")]
     Azure(azure::azure_hl::StrokeOptions<'a>),
-    #[cfg(feature = "raqote_backend")]
+    #[cfg(feature = "canvas2d-raqote")]
     Raqote(PhantomData<&'a ()>),
 }
 
@@ -391,12 +391,12 @@ pub struct CanvasData<'a> {
     pub canvas_id: CanvasId,
 }
 
-#[cfg(feature = "azure_backend")]
+#[cfg(feature = "canvas2d-azure")]
 fn create_backend() -> Box<dyn Backend> {
     Box::new(crate::azure_backend::AzureBackend)
 }
 
-#[cfg(feature = "raqote_backend")]
+#[cfg(feature = "canvas2d-raqote")]
 fn create_backend() -> Box<dyn Backend> {
     Box::new(crate::raqote_backend::RaqoteBackend)
 }
diff --git a/components/canvas/lib.rs b/components/canvas/lib.rs
index 28dd1e04f5d..ba10f02636c 100644
--- a/components/canvas/lib.rs
+++ b/components/canvas/lib.rs
@@ -7,10 +7,10 @@
 #[macro_use]
 extern crate log;
 
-#[cfg(feature = "azure_backend")]
+#[cfg(feature = "canvas2d-azure")]
 mod azure_backend;
 
-#[cfg(feature = "raqote_backend")]
+#[cfg(feature = "canvas2d-raqote")]
 mod raqote_backend;
 
 pub mod canvas_data;
diff --git a/components/constellation/Cargo.toml b/components/constellation/Cargo.toml
index 0831cd33b0c..718e537e64b 100644
--- a/components/constellation/Cargo.toml
+++ b/components/constellation/Cargo.toml
@@ -11,8 +11,8 @@ name = "constellation"
 path = "lib.rs"
 
 [features]
-azure_backend = ["canvas/azure_backend"]
-raqote_backend = ["canvas/raqote_backend"]
+canvas2d-azure = ["canvas/canvas2d-azure"]
+canvas2d-raqote = ["canvas/canvas2d-raqote"]
 no_wgl = ["canvas/no_wgl"]
 
 [dependencies]
diff --git a/components/constellation/lib.rs b/components/constellation/lib.rs
index 2beee10e78d..b102a0bc2b5 100644
--- a/components/constellation/lib.rs
+++ b/components/constellation/lib.rs
@@ -3,7 +3,6 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 #![deny(unsafe_code)]
-#![cfg_attr(feature = "unstable", feature(conservative_impl_trait))]
 
 #[macro_use]
 extern crate crossbeam_channel;
diff --git a/components/gfx/Cargo.toml b/components/gfx/Cargo.toml
index 3818a2f30a6..a95fb6d1046 100644
--- a/components/gfx/Cargo.toml
+++ b/components/gfx/Cargo.toml
@@ -13,9 +13,6 @@ path = "lib.rs"
 test = false
 doctest = false
 
-[features]
-unstable = ["packed_simd"]
-
 [dependencies]
 app_units = "0.7"
 bitflags = "1.0"
@@ -31,7 +28,7 @@ log = "0.4"
 malloc_size_of = { path = "../malloc_size_of" }
 net_traits = {path = "../net_traits"}
 ordered-float = "1.0"
-packed_simd = {version = "0.3", optional = true}
+packed_simd = "0.3"
 range = {path = "../range"}
 serde = "1.0"
 servo_arc = {path = "../servo_arc"}
diff --git a/components/gfx/text/glyph.rs b/components/gfx/text/glyph.rs
index df8180688f0..82d002e61f4 100644
--- a/components/gfx/text/glyph.rs
+++ b/components/gfx/text/glyph.rs
@@ -4,10 +4,7 @@
 
 use app_units::Au;
 use euclid::Point2D;
-#[cfg(all(
-    feature = "unstable",
-    any(target_feature = "sse2", target_feature = "neon")
-))]
+#[cfg(any(target_feature = "sse2", target_feature = "neon"))]
 use packed_simd::u32x4;
 use range::{self, EachIndex, Range, RangeIndex};
 use std::cmp::{Ordering, PartialOrd};
@@ -75,7 +72,6 @@ pub type GlyphId = u32;
 // TODO: make this more type-safe.
 
 const FLAG_CHAR_IS_SPACE: u32 = 0x40000000;
-#[cfg(feature = "unstable")]
 #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
 const FLAG_CHAR_IS_SPACE_SHIFT: u32 = 30;
 const FLAG_IS_SIMPLE_GLYPH: u32 = 0x80000000;
@@ -625,7 +621,6 @@ impl<'a> GlyphStore {
     }
 
     #[inline]
-    #[cfg(feature = "unstable")]
     #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
     fn advance_for_byte_range_simple_glyphs(
         &self,
@@ -644,7 +639,7 @@ impl<'a> GlyphStore {
 
         for i in 0..num_simd_iterations {
             let offset = begin + i * 4;
-            let v = u32x4::load_unaligned(&buf[offset..]);
+            let v = u32x4::from_slice_unaligned(&buf[offset..]);
             let advance = (v & advance_mask) >> GLYPH_ADVANCE_SHIFT;
             let spaces = (v & space_flag_mask) >> FLAG_CHAR_IS_SPACE_SHIFT;
             simd_advance = simd_advance + advance;
@@ -672,10 +667,7 @@ impl<'a> GlyphStore {
 
     /// When SIMD isn't available, fallback to the slow path.
     #[inline]
-    #[cfg(not(all(
-        feature = "unstable",
-        any(target_feature = "sse2", target_feature = "neon")
-    )))]
+    #[cfg(not(any(target_feature = "sse2", target_feature = "neon")))]
     fn advance_for_byte_range_simple_glyphs(
         &self,
         range: &Range<ByteIndex>,
@@ -686,7 +678,6 @@ impl<'a> GlyphStore {
 
     /// Used for SIMD.
     #[inline]
-    #[cfg(feature = "unstable")]
     #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
     #[allow(unsafe_code)]
     fn transmute_entry_buffer_to_u32_buffer(&self) -> &[u32] {
diff --git a/components/layout_thread/Cargo.toml b/components/layout_thread/Cargo.toml
index 8c98a809c1a..9ae8a6f953d 100644
--- a/components/layout_thread/Cargo.toml
+++ b/components/layout_thread/Cargo.toml
@@ -10,9 +10,6 @@ publish = false
 name = "layout_thread"
 path = "lib.rs"
 
-[features]
-unstable = ["parking_lot/nightly"]
-
 [dependencies]
 app_units = "0.7"
 atomic_refcell = "0.1"
@@ -36,7 +33,7 @@ malloc_size_of = { path = "../malloc_size_of" }
 metrics = {path = "../metrics"}
 msg = {path = "../msg"}
 net_traits = {path = "../net_traits"}
-parking_lot = "0.8"
+parking_lot = {version = "0.8", features = ["nightly"]}
 profile_traits = {path = "../profile_traits"}
 range = {path = "../range"}
 rayon = "1"
diff --git a/components/profile/Cargo.toml b/components/profile/Cargo.toml
index c1d14c3c31a..baf7d340cb2 100644
--- a/components/profile/Cargo.toml
+++ b/components/profile/Cargo.toml
@@ -10,9 +10,6 @@ publish = false
 name = "profile"
 path = "lib.rs"
 
-[features]
-unstable = ["servo_allocator"]
-
 [dependencies]
 profile_traits = {path = "../profile_traits"}
 influent = "0.5"
@@ -33,4 +30,4 @@ regex = "1.1"
 
 [target.'cfg(not(target_os = "windows"))'.dependencies]
 libc = "0.2"
-servo_allocator = {path = "../allocator", optional = true}
+servo_allocator = {path = "../allocator"}
diff --git a/components/profile/mem.rs b/components/profile/mem.rs
index cf67560ad83..bb4688f397c 100644
--- a/components/profile/mem.rs
+++ b/components/profile/mem.rs
@@ -389,14 +389,14 @@ mod system_reporter {
     use super::{JEMALLOC_HEAP_ALLOCATED_STR, SYSTEM_HEAP_ALLOCATED_STR};
     #[cfg(target_os = "linux")]
     use libc::c_int;
-    #[cfg(all(feature = "unstable", not(target_os = "windows")))]
+    #[cfg(not(target_os = "windows"))]
     use libc::{c_void, size_t};
     use profile_traits::mem::{Report, ReportKind, ReporterRequest};
-    #[cfg(all(feature = "unstable", not(target_os = "windows")))]
+    #[cfg(not(target_os = "windows"))]
     use std::ffi::CString;
-    #[cfg(all(feature = "unstable", not(target_os = "windows")))]
+    #[cfg(not(target_os = "windows"))]
     use std::mem::size_of;
-    #[cfg(all(feature = "unstable", not(target_os = "windows")))]
+    #[cfg(not(target_os = "windows"))]
     use std::ptr::null_mut;
     #[cfg(target_os = "macos")]
     use task_info::task_basic_info::{resident_size, virtual_size};
@@ -495,10 +495,10 @@ mod system_reporter {
         None
     }
 
-    #[cfg(all(feature = "unstable", not(target_os = "windows")))]
+    #[cfg(not(target_os = "windows"))]
     use servo_allocator::jemalloc_sys::mallctl;
 
-    #[cfg(all(feature = "unstable", not(target_os = "windows")))]
+    #[cfg(not(target_os = "windows"))]
     fn jemalloc_stat(value_name: &str) -> Option<usize> {
         // Before we request the measurement of interest, we first send an "epoch"
         // request. Without that jemalloc gives cached statistics(!) which can be
@@ -545,7 +545,7 @@ mod system_reporter {
         Some(value as usize)
     }
 
-    #[cfg(any(target_os = "windows", not(feature = "unstable")))]
+    #[cfg(target_os = "windows")]
     fn jemalloc_stat(_value_name: &str) -> Option<usize> {
         None
     }
diff --git a/components/script/Cargo.toml b/components/script/Cargo.toml
index deeb5f7a3bf..1b9dade72eb 100644
--- a/components/script/Cargo.toml
+++ b/components/script/Cargo.toml
@@ -15,7 +15,6 @@ path = "lib.rs"
 [features]
 debugmozjs = ['js/debugmozjs']
 profilemozjs = ['js/profilemozjs']
-unstable = []
 unrooted_must_root_lint = ["script_plugins/unrooted_must_root_lint"]
 webidl_lint = ["script_plugins/webidl_lint"]
 default = ["unrooted_must_root_lint", "webidl_lint"]
diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index 161354479b6..442648fb9c8 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -69,10 +69,7 @@ pub trait IDLInterface {
 }
 
 /// A trait to mark an IDL interface as deriving from another one.
-#[cfg_attr(
-    feature = "unstable",
-    rustc_on_unimplemented(message = "The IDL interface `{Self}` is not derived from `{T}`.")
-)]
+#[rustc_on_unimplemented(message = "The IDL interface `{Self}` is not derived from `{T}`.")]
 pub trait DerivedFrom<T: Castable>: Castable {}
 
 impl<T: Float + ToJSValConvertible> ToJSValConvertible for Finite<T> {
diff --git a/components/script/dom/bindings/root.rs b/components/script/dom/bindings/root.rs
index 228015b1275..c87c83a2469 100644
--- a/components/script/dom/bindings/root.rs
+++ b/components/script/dom/bindings/root.rs
@@ -330,13 +330,13 @@ impl<T: DomObject> Deref for Dom<T> {
 
 unsafe impl<T: DomObject> JSTraceable for Dom<T> {
     unsafe fn trace(&self, trc: *mut JSTracer) {
-        #[cfg(all(feature = "unstable", debug_assertions))]
-        let trace_str = format!("for {} on heap", ::std::intrinsics::type_name::<T>());
-        #[cfg(all(feature = "unstable", debug_assertions))]
-        let trace_info = &trace_str[..];
-        #[cfg(not(all(feature = "unstable", debug_assertions)))]
-        let trace_info = "for DOM object on heap";
-
+        let trace_string;
+        let trace_info = if cfg!(debug_assertions) {
+            trace_string = format!("for {} on heap", ::std::intrinsics::type_name::<T>());
+            &trace_string[..]
+        } else {
+            "for DOM object on heap"
+        };
         trace_reflector(trc, trace_info, (*self.ptr.as_ptr()).reflector());
     }
 }
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index a1afdc34a82..596fd711599 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -938,10 +938,7 @@ impl WindowMethods for Window {
 
     #[allow(unsafe_code)]
     fn Trap(&self) {
-        #[cfg(feature = "unstable")]
-        unsafe {
-            ::std::intrinsics::breakpoint()
-        }
+        unsafe { ::std::intrinsics::breakpoint() }
     }
 
     #[allow(unsafe_code)]
diff --git a/components/script/lib.rs b/components/script/lib.rs
index 9bc2d929b13..1be386dfd1c 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -2,11 +2,11 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-#![cfg_attr(feature = "unstable", feature(core_intrinsics))]
-#![cfg_attr(feature = "unstable", feature(on_unimplemented))]
 #![feature(const_fn)]
+#![feature(core_intrinsics)]
 #![feature(drain_filter)]
 #![feature(inner_deref)]
+#![feature(on_unimplemented)]
 #![feature(plugin)]
 #![feature(type_alias_enum_variants)]
 #![deny(unsafe_code)]
diff --git a/components/script/task.rs b/components/script/task.rs
index c8b4b438deb..61f9bf436dd 100644
--- a/components/script/task.rs
+++ b/components/script/task.rs
@@ -32,14 +32,7 @@ macro_rules! task {
 pub trait TaskOnce: Send {
     #[allow(unsafe_code)]
     fn name(&self) -> &'static str {
-        #[cfg(feature = "unstable")]
-        unsafe {
-            ::std::intrinsics::type_name::<Self>()
-        }
-        #[cfg(not(feature = "unstable"))]
-        {
-            "(task name unknown)"
-        }
+        unsafe { ::std::intrinsics::type_name::<Self>() }
     }
 
     fn run_once(self);
diff --git a/components/servo/Cargo.toml b/components/servo/Cargo.toml
index 7d03959d767..de870ef2e0f 100644
--- a/components/servo/Cargo.toml
+++ b/components/servo/Cargo.toml
@@ -12,7 +12,8 @@ path = "lib.rs"
 crate-type = ["rlib"]
 
 [features]
-azure_backend = ["canvas/azure_backend"]
+canvas2d-azure = ["canvas/canvas2d-azure"]
+canvas2d-raqote = ["canvas/canvas2d-raqote"]
 debugmozjs = ["script/debugmozjs"]
 energy-profiling = ["profile_traits/energy-profiling"]
 profilemozjs = ["script/profilemozjs"]
@@ -21,16 +22,10 @@ js_backtrace = ["script/js_backtrace"]
 max_log_level = ["log/release_max_level_info"]
 native-bluetooth = ["bluetooth/native-bluetooth"]
 no_wgl = ["canvas/no_wgl"]
-raqote_backend = ["canvas/raqote_backend"]
 uwp = ["servo_config/uwp"]
 webrender_debugger = ["webrender/debugger"]
 no_static_freetype = ["webrender/no_static_freetype"]
 oculusvr = ["webvr/oculusvr"]
-unstable = [
-    "euclid/unstable",
-    "profile/unstable",
-    "script/unstable",
-]
 webdriver = ["webdriver_server"]
 webgl_backtrace = [
     "script/webgl_backtrace",
diff --git a/etc/taskcluster/decision_task.py b/etc/taskcluster/decision_task.py
index e8e6479c052..3bcd1db3658 100644
--- a/etc/taskcluster/decision_task.py
+++ b/etc/taskcluster/decision_task.py
@@ -183,9 +183,8 @@ def linux_tidy_unit_docs():
             ./mach build --dev
             ./mach test-unit
             ./mach package --dev
-            ./mach build --dev --features raqote_backend
+            ./mach build --dev --features canvas2d-raqote
             ./mach build --dev --libsimpleservo
-            ./mach build --dev --no-default-features --features default-except-unstable
             ./mach test-tidy --no-progress --self-test
 
             ./etc/memory_reports_over_time.py --test
@@ -194,12 +193,24 @@ def linux_tidy_unit_docs():
             ./etc/ci/check_no_panic.sh
 
             RUSTDOCFLAGS="--disable-minification" ./mach doc
-            cd target/doc
-            git init
-            time git add .
-            git -c user.name="Taskcluster" -c user.email="" \
-                commit -q -m "Rebuild Servo documentation"
-            git bundle create docs.bundle HEAD
+            (
+                cd target/doc
+                git init
+                git add .
+                git -c user.name="Taskcluster" -c user.email="" \
+                    commit -q -m "Rebuild Servo documentation"
+                git bundle create docs.bundle HEAD
+            )
+
+        """
+        # Because `rustdoc` needs metadata of dependency crates,
+        # `cargo doc` does almost all of the work that `cargo check` does.
+        # Therefore, when running them in this order the second command does very little
+        # and should finish quickly.
+        # The reverse order would not increase the total amount of work to do,
+        # but would reduce the amount of parallelism available.
+        """
+            ./mach check
         """)
         .with_artifacts("/repo/target/doc/docs.bundle")
         .find_or_create("docs." + CONFIG.task_id())
diff --git a/ports/glutin/Cargo.toml b/ports/glutin/Cargo.toml
index 54ddcb769cb..a75452b2660 100644
--- a/ports/glutin/Cargo.toml
+++ b/ports/glutin/Cargo.toml
@@ -27,17 +27,15 @@ OriginalFilename = "servo.exe"
 ProductName = "Servo"
 
 [features]
-azure_backend = ["libservo/azure_backend"]
-default = ["unstable", "default-except-unstable"]
-default-except-unstable = ["webdriver", "max_log_level"]
+canvas2d-azure = ["libservo/canvas2d-azure"]
+canvas2d-raqote = ["libservo/canvas2d-raqote"]
+default = ["webdriver", "max_log_level"]
 energy-profiling = ["libservo/energy-profiling"]
 debugmozjs = ["libservo/debugmozjs"]
 js_backtrace = ["libservo/js_backtrace"]
 max_log_level = ["log/release_max_level_info"]
 native-bluetooth = ["libservo/native-bluetooth"]
 profilemozjs = ["libservo/profilemozjs"]
-raqote_backend = ["libservo/raqote_backend"]
-unstable = ["libservo/unstable"]
 webdriver = ["libservo/webdriver"]
 webgl_backtrace = ["libservo/webgl_backtrace"]
 webrender_debugger = ["libservo/webrender_debugger"]
diff --git a/ports/glutin/main.rs b/ports/glutin/main.rs
index 23be648bad8..50da58121bc 100644
--- a/ports/glutin/main.rs
+++ b/ports/glutin/main.rs
@@ -15,7 +15,7 @@
 //!
 //! [glutin]: https://github.com/tomaka/glutin
 
-#![cfg_attr(feature = "unstable", feature(core_intrinsics))]
+#![feature(core_intrinsics)]
 
 #[cfg(not(target_os = "android"))]
 include!("main2.rs");
diff --git a/ports/glutin/main2.rs b/ports/glutin/main2.rs
index 496c0515e19..579c97d3a23 100644
--- a/ports/glutin/main2.rs
+++ b/ports/glutin/main2.rs
@@ -6,7 +6,7 @@
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-#[cfg(all(feature = "unstable", any(target_os = "macos", target_os = "linux")))]
+#[cfg(any(target_os = "macos", target_os = "linux"))]
 #[macro_use]
 extern crate sig;
 
@@ -42,13 +42,10 @@ pub mod platform {
     pub fn deinit() {}
 }
 
-#[cfg(any(
-    not(feature = "unstable"),
-    not(any(target_os = "macos", target_os = "linux"))
-))]
+#[cfg(not(any(target_os = "macos", target_os = "linux")))]
 fn install_crash_handler() {}
 
-#[cfg(all(feature = "unstable", any(target_os = "macos", target_os = "linux")))]
+#[cfg(any(target_os = "macos", target_os = "linux"))]
 fn install_crash_handler() {
     use backtrace::Backtrace;
     use libc::_exit;
diff --git a/ports/libmlservo/Cargo.toml b/ports/libmlservo/Cargo.toml
index ac04dc44c0f..0c8389269c3 100644
--- a/ports/libmlservo/Cargo.toml
+++ b/ports/libmlservo/Cargo.toml
@@ -13,8 +13,8 @@ test = false
 bench = false
 
 [features]
-azure_backend = ["simpleservo/azure_backend"]
-raqote_backend = ["simpleservo/raqote_backend"]
+canvas2d-azure = ["simpleservo/canvas2d-azure"]
+canvas2d-raqote = ["simpleservo/canvas2d-raqote"]
 
 [dependencies]
 libservo = { path = "../../components/servo", features = ["no_static_freetype"] }
diff --git a/ports/libsimpleservo/api/Cargo.toml b/ports/libsimpleservo/api/Cargo.toml
index 8e1726a8b02..68f0b7f1816 100644
--- a/ports/libsimpleservo/api/Cargo.toml
+++ b/ports/libsimpleservo/api/Cargo.toml
@@ -26,9 +26,9 @@ libloading = "0.5"
 gl_generator = "0.11"
 
 [features]
-azure_backend = ["libservo/azure_backend"]
-default = ["unstable", "default-except-unstable"]
-default-except-unstable = ["webdriver", "max_log_level"]
+canvas2d-azure = ["libservo/canvas2d-azure"]
+canvas2d-raqote = ["libservo/canvas2d-raqote"]
+default = ["webdriver", "max_log_level"]
 debugmozjs = ["libservo/debugmozjs"]
 energy-profiling = ["libservo/energy-profiling"]
 googlevr = ["libservo/googlevr"]
@@ -38,8 +38,6 @@ native-bluetooth = ["libservo/native-bluetooth"]
 no_static_freetype = ["libservo/no_static_freetype"]
 no_wgl = ["libservo/no_wgl"]
 oculusvr = ["libservo/oculusvr"]
-raqote_backend = ["libservo/raqote_backend"]
 webdriver = ["libservo/webdriver"]
-unstable = ["libservo/unstable"]
 uwp = ["libservo/uwp"]
 webgl_backtrace = ["libservo/webgl_backtrace"]
diff --git a/ports/libsimpleservo/capi/Cargo.toml b/ports/libsimpleservo/capi/Cargo.toml
index 1ca469d82c0..8bcf34aad0b 100644
--- a/ports/libsimpleservo/capi/Cargo.toml
+++ b/ports/libsimpleservo/capi/Cargo.toml
@@ -21,10 +21,10 @@ env_logger = "0.6"
 cbindgen = "0.8"
 
 [features]
-azure_backend = ["simpleservo/azure_backend"]
+canvas2d-azure = ["simpleservo/canvas2d-azure"]
+canvas2d-raqote = ["simpleservo/canvas2d-raqote"]
 debugmozjs = ["simpleservo/debugmozjs"]
-default = ["unstable", "default-except-unstable"]
-default-except-unstable = ["webdriver", "max_log_level"]
+default = ["webdriver", "max_log_level"]
 energy-profiling = ["simpleservo/energy-profiling"]
 googlevr = ["simpleservo/googlevr"]
 js_backtrace = ["simpleservo/js_backtrace"]
@@ -32,8 +32,6 @@ max_log_level = ["simpleservo/max_log_level"]
 native-bluetooth = ["simpleservo/native-bluetooth"]
 no_wgl = ["simpleservo/no_wgl"]
 oculusvr = ["simpleservo/oculusvr"]
-raqote_backend = ["simpleservo/raqote_backend"]
-unstable = ["simpleservo/unstable"]
 uwp = ["simpleservo/uwp"]
 webdriver = ["simpleservo/webdriver"]
 webgl_backtrace = ["simpleservo/webgl_backtrace"]
diff --git a/ports/libsimpleservo/jniapi/Cargo.toml b/ports/libsimpleservo/jniapi/Cargo.toml
index 95a841770a0..98838fafcb3 100644
--- a/ports/libsimpleservo/jniapi/Cargo.toml
+++ b/ports/libsimpleservo/jniapi/Cargo.toml
@@ -26,17 +26,15 @@ simpleservo = { path = "../api" }
 cc = "1.0"
 
 [features]
-azure_backend = ["simpleservo/azure_backend"]
+canvas2d-azure = ["simpleservo/canvas2d-azure"]
+canvas2d-raqote = ["simpleservo/canvas2d-raqote"]
 debugmozjs = ["simpleservo/debugmozjs"]
-default = ["unstable", "default-except-unstable"]
-default-except-unstable = ["webdriver", "max_log_level"]
+default = ["webdriver", "max_log_level"]
 energy-profiling = ["simpleservo/energy-profiling"]
 googlevr = ["simpleservo/googlevr"]
 js_backtrace = ["simpleservo/js_backtrace"]
 max_log_level = ["simpleservo/max_log_level"]
 native-bluetooth = ["simpleservo/native-bluetooth"]
 oculusvr = ["simpleservo/oculusvr"]
-raqote_backend = ["simpleservo/raqote_backend"]
-unstable = ["simpleservo/unstable"]
 webdriver = ["simpleservo/webdriver"]
 webgl_backtrace = ["simpleservo/webgl_backtrace"]
diff --git a/python/servo/bootstrap_commands.py b/python/servo/bootstrap_commands.py
index a2df3aaef33..605b78362d8 100644
--- a/python/servo/bootstrap_commands.py
+++ b/python/servo/bootstrap_commands.py
@@ -34,18 +34,6 @@ from servo.util import delete, download_bytes, download_file, extract, check_has
 
 @CommandProvider
 class MachCommands(CommandBase):
-    @Command('env',
-             description='Print environment setup commands',
-             category='bootstrap')
-    def env(self):
-        env = self.build_env()
-        print("export RUSTFLAGS=%s" % env.get("RUSTFLAGS", ""))
-        print("export PATH=%s" % env.get("PATH", ""))
-        if sys.platform == "darwin":
-            print("export DYLD_LIBRARY_PATH=%s" % env.get("DYLD_LIBRARY_PATH", ""))
-        else:
-            print("export LD_LIBRARY_PATH=%s" % env.get("LD_LIBRARY_PATH", ""))
-
     @Command('bootstrap',
              description='Install required packages for building.',
              category='bootstrap')
diff --git a/python/servo/build_commands.py b/python/servo/build_commands.py
index 2010bfbce9b..3937b73efd0 100644
--- a/python/servo/build_commands.py
+++ b/python/servo/build_commands.py
@@ -146,9 +146,6 @@ class MachCommands(CommandBase):
     @Command('build',
              description='Build Servo',
              category='build')
-    @CommandArgument('--target', '-t',
-                     default=None,
-                     help='Cross compile for given target platform')
     @CommandArgument('--release', '-r',
                      action='store_true',
                      help='Build in release mode')
@@ -158,25 +155,9 @@ class MachCommands(CommandBase):
     @CommandArgument('--jobs', '-j',
                      default=None,
                      help='Number of jobs to run in parallel')
-    @CommandArgument('--features',
-                     default=None,
-                     help='Space-separated list of features to also build',
-                     nargs='+')
-    @CommandArgument('--android',
-                     default=None,
-                     action='store_true',
-                     help='Build for Android')
-    @CommandArgument('--magicleap',
-                     default=None,
-                     action='store_true',
-                     help='Build for Magic Leap')
     @CommandArgument('--no-package',
                      action='store_true',
                      help='For Android, disable packaging into a .apk after building')
-    @CommandArgument('--debug-mozjs',
-                     default=None,
-                     action='store_true',
-                     help='Enable debug assertions in mozjs')
     @CommandArgument('--verbose', '-v',
                      action='store_true',
                      help='Print verbose output')
@@ -185,46 +166,14 @@ class MachCommands(CommandBase):
                      help='Print very verbose output')
     @CommandArgument('params', nargs='...',
                      help="Command-line arguments to be passed through to Cargo")
-    @CommandArgument('--with-debug-assertions',
-                     default=None,
-                     action='store_true',
-                     help='Enable debug assertions in release')
-    @CommandArgument('--libsimpleservo',
-                     default=None,
-                     action='store_true',
-                     help='Build the libsimpleservo library instead of the servo executable')
-    @CommandArgument('--with-frame-pointer',
-                     default=None,
-                     action='store_true',
-                     help='Build with frame pointer enabled, used by the background hang monitor.')
-    @CommandArgument('--with-raqote', default=None, action='store_true')
-    @CommandArgument('--without-wgl', default=None, action='store_true')
-    def build(self, target=None, release=False, dev=False, jobs=None,
-              features=None, android=None, magicleap=None, no_package=False, verbose=False, very_verbose=False,
-              debug_mozjs=False, params=None, with_debug_assertions=False,
-              libsimpleservo=False, with_frame_pointer=False, with_raqote=False, without_wgl=False):
-
+    @CommandBase.build_like_command_arguments
+    def build(self, release=False, dev=False, jobs=None, params=None,
+              no_package=False, verbose=False, very_verbose=False,
+              target=None, android=False, magicleap=False, libsimpleservo=False,
+              features=None, **kwargs):
         opts = params or []
-
-        if android is None:
-            android = self.config["build"]["android"]
-        features = features or self.servo_features()
-
-        if target and android:
-            print("Please specify either --target or --android.")
-            sys.exit(1)
-
-        if android:
-            target = self.config["android"]["target"]
-
-        if not magicleap:
-            features += ["native-bluetooth"]
-
-        if magicleap and not target:
-            target = "aarch64-linux-android"
-
-        if target and not android and not magicleap:
-            android = self.handle_android_target(target)
+        features = features or []
+        target, android = self.pick_target_triple(target, android, magicleap)
 
         target_path = base_path = self.get_target_dir()
         if android:
@@ -278,44 +227,13 @@ class MachCommands(CommandBase):
                 check_call(["rustup" + BIN_SUFFIX, "target", "add",
                             "--toolchain", self.toolchain(), target])
 
-            opts += ["--target", target]
-
         env = self.build_env(target=target, is_build=True)
         self.ensure_bootstrapped(target=target)
         self.ensure_clobbered()
 
-        self.add_manifest_path(opts, android, libsimpleservo)
-
-        if debug_mozjs:
-            features += ["debugmozjs"]
-
-        if with_frame_pointer:
-            env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " -C force-frame-pointers=yes"
-            features += ["profilemozjs"]
-
-        if with_raqote:
-            features += ["raqote_backend"]
-
-        if without_wgl:
-            features += ["no_wgl"]
-
-        if self.config["build"]["webgl-backtrace"]:
-            features += ["webgl-backtrace"]
-        if self.config["build"]["dom-backtrace"]:
-            features += ["dom-backtrace"]
-
-        if "raqote_backend" not in features:
-            features += ["azure_backend"]
-
-        if features:
-            opts += ["--features", "%s" % ' '.join(features)]
-
         build_start = time()
         env["CARGO_TARGET_DIR"] = target_path
 
-        if with_debug_assertions:
-            env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " -C debug_assertions"
-
         host = host_triple()
         if 'apple-darwin' in host and (not target or target == host):
             if 'CXXFLAGS' not in env:
@@ -612,7 +530,13 @@ class MachCommands(CommandBase):
             env.setdefault("CC", "clang")
             env.setdefault("CXX", "clang++")
 
-        status = self.call_rustup_run(["cargo", "build"] + opts, env=env, verbose=verbose)
+        status = self.run_cargo_build_like_command(
+            "build", opts, env=env, verbose=verbose,
+            target=target, android=android, magicleap=magicleap, libsimpleservo=libsimpleservo,
+            features=features, **kwargs
+        )
+        status = 0
+
         elapsed = time() - build_start
 
         # Do some additional things if the build succeeded
@@ -712,14 +636,11 @@ class MachCommands(CommandBase):
             print('Removing virtualenv directory: %s' % virtualenv_path)
             shutil.rmtree(virtualenv_path)
 
-        opts = []
-        if manifest_path:
-            opts += ["--manifest-path", manifest_path]
+        opts = ["--manifest-path", manifest_path or path.join(self.context.topdir, "Cargo.toml")]
         if verbose:
             opts += ["-v"]
         opts += params
-        return check_call(["cargo", "clean"] + opts,
-                          env=self.build_env(), cwd=self.ports_glutin_crate(), verbose=verbose)
+        return check_call(["cargo", "clean"] + opts, env=self.build_env(), verbose=verbose)
 
 
 def package_gstreamer_dlls(servo_exe_dir, target):
diff --git a/python/servo/command_base.py b/python/servo/command_base.py
index 0b7ed2cf50b..838e03f910c 100644
--- a/python/servo/command_base.py
+++ b/python/servo/command_base.py
@@ -28,6 +28,7 @@ from servo.util import download_file
 import urllib2
 from bootstrap import check_gstreamer_lib
 
+from mach.decorators import CommandArgument
 from mach.registrar import Registrar
 import toml
 
@@ -731,34 +732,130 @@ install them, let us know by filing a bug!")
 
         return env
 
-    def ports_glutin_crate(self):
-        return path.join(self.context.topdir, "ports", "glutin")
-
-    def add_manifest_path(self, args, android=False, libsimpleservo=False):
+    @staticmethod
+    def build_like_command_arguments(decorated_function):
+        decorators = [
+            CommandArgument(
+                '--target', '-t',
+                default=None,
+                help='Cross compile for given target platform',
+            ),
+            CommandArgument(
+                '--android',
+                default=None,
+                action='store_true',
+                help='Build for Android',
+            ),
+            CommandArgument(
+                '--magicleap',
+                default=None,
+                action='store_true',
+                help='Build for Magic Leap',
+            ),
+            CommandArgument(
+                '--libsimpleservo',
+                default=None,
+                action='store_true',
+                help='Build the libsimpleservo library instead of the servo executable',
+            ),
+            CommandArgument(
+                '--features',
+                default=None,
+                help='Space-separated list of features to also build',
+                nargs='+',
+            ),
+            CommandArgument(
+                '--debug-mozjs',
+                default=None,
+                action='store_true',
+                help='Enable debug assertions in mozjs',
+            ),
+            CommandArgument(
+                '--with-debug-assertions',
+                default=None,
+                action='store_true',
+                help='Enable debug assertions in release',
+            ),
+            CommandArgument(
+                '--with-frame-pointer',
+                default=None,
+                action='store_true',
+                help='Build with frame pointer enabled, used by the background hang monitor.',
+            ),
+            CommandArgument('--with-raqote', default=None, action='store_true'),
+            CommandArgument('--without-wgl', default=None, action='store_true'),
+        ]
+
+        for decorator in decorators:
+            decorated_function = decorator(decorated_function)
+        return decorated_function
+
+    def pick_target_triple(self, target, android, magicleap):
+        if android is None:
+            android = self.config["build"]["android"]
+        if target and android:
+            assert self.handle_android_target(target)
+        if android and not target:
+            target = self.config["android"]["target"]
+        if magicleap and not target:
+            target = "aarch64-linux-android"
+        if target and not android and not magicleap:
+            android = self.handle_android_target(target)
+        return target, android
+
+    def run_cargo_build_like_command(
+        self, command, cargo_args,
+        env=None, verbose=False,
+        target=None, android=False, magicleap=False, libsimpleservo=False,
+        features=None, debug_mozjs=False, with_debug_assertions=False,
+        with_frame_pointer=False, with_raqote=False, without_wgl=False,
+    ):
+        env = env or self.build_env()
+        target, android = self.pick_target_triple(target, android, magicleap)
+
+        args = []
         if "--manifest-path" not in args:
             if libsimpleservo or android:
-                manifest = self.ports_libsimpleservo_manifest(android)
+                if android:
+                    api = "jniapi"
+                else:
+                    api = "capi"
+                port = path.join("libsimpleservo", api)
             else:
-                manifest = self.ports_glutin_manifest()
-            args.append("--manifest-path")
-            args.append(manifest)
-
-    def ports_glutin_manifest(self):
-        return path.join(self.context.topdir, "ports", "glutin", "Cargo.toml")
-
-    def ports_libsimpleservo_manifest(self, android=False):
-        if android:
-            api = "jniapi"
-        else:
-            api = "capi"
-        return path.join(self.context.topdir, "ports", "libsimpleservo", api, "Cargo.toml")
-
-    def servo_features(self):
-        """Return a list of optional features to enable for the Servo crate"""
-        features = []
-        if self.config["build"]["debug-mozjs"]:
-            features += ["debugmozjs"]
-        return features
+                port = "glutin"
+            args += [
+                "--manifest-path",
+                path.join(self.context.topdir, "ports", port, "Cargo.toml"),
+            ]
+        if target:
+            args += ["--target", target]
+
+        if features is None:  # If we're passed a list, mutate it even if it's empty
+            features = []
+        if self.config["build"]["debug-mozjs"] or debug_mozjs:
+            features.append("debugmozjs")
+        if not magicleap:
+            features.append("native-bluetooth")
+        if with_raqote and "canvas2d-azure" not in features:
+            features.append("canvas2d-raqote")
+        elif "canvas2d-raqote" not in features:
+            features.append("canvas2d-azure")
+        if with_frame_pointer:
+            env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " -C force-frame-pointers=yes"
+            features.append("profilemozjs")
+        if without_wgl:
+            features.append("no_wgl")
+        if self.config["build"]["webgl-backtrace"]:
+            features.append("webgl-backtrace")
+        if self.config["build"]["dom-backtrace"]:
+            features.append("dom-backtrace")
+        if with_debug_assertions:
+            env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " -C debug_assertions"
+
+        assert "--features" not in cargo_args
+        args += ["--features", " ".join(features)]
+
+        return self.call_rustup_run(["cargo", command] + args + cargo_args, env=env, verbose=verbose)
 
     def android_support_dir(self):
         return path.join(self.context.topdir, "support", "android")
diff --git a/python/servo/devenv_commands.py b/python/servo/devenv_commands.py
index b298bf48fd1..ad5a02c270d 100644
--- a/python/servo/devenv_commands.py
+++ b/python/servo/devenv_commands.py
@@ -31,7 +31,14 @@ from servo.util import get_static_rust_lang_org_dist, get_urlopen_kwargs
 
 @CommandProvider
 class MachCommands(CommandBase):
-    def run_cargo(self, params, check=False):
+    @Command('check',
+             description='Run "cargo check"',
+             category='devenv')
+    @CommandArgument(
+        'params', default=None, nargs='...',
+        help="Command-line arguments to be passed through to cargo check")
+    @CommandBase.build_like_command_arguments
+    def check(self, params, **kwargs):
         if not params:
             params = []
 
@@ -39,40 +46,17 @@ class MachCommands(CommandBase):
         self.ensure_clobbered()
         env = self.build_env()
 
-        if check:
-            params = ['check'] + params
-
-        self.add_manifest_path(params)
-
         build_start = time()
-        status = self.call_rustup_run(["cargo"] + params, env=env)
+        status = self.run_cargo_build_like_command("check", params, env=env, **kwargs)
         elapsed = time() - build_start
 
         notify_build_done(self.config, elapsed, status == 0)
 
-        if check and status == 0:
+        if status == 0:
             print('Finished checking, binary NOT updated. Consider ./mach build before ./mach run')
 
         return status
 
-    @Command('cargo',
-             description='Run Cargo',
-             category='devenv')
-    @CommandArgument(
-        'params', default=None, nargs='...',
-        help="Command-line arguments to be passed through to Cargo")
-    def cargo(self, params):
-        return self.run_cargo(params)
-
-    @Command('check',
-             description='Run "cargo check"',
-             category='devenv')
-    @CommandArgument(
-        'params', default=None, nargs='...',
-        help="Command-line arguments to be passed through to cargo check")
-    def check(self, params):
-        return self.run_cargo(params, check=True)
-
     @Command('cargo-update',
              description='Same as update-cargo',
              category='devenv')
diff --git a/python/servo/post_build_commands.py b/python/servo/post_build_commands.py
index 42e2ad84cb4..b9dc9b080ef 100644
--- a/python/servo/post_build_commands.py
+++ b/python/servo/post_build_commands.py
@@ -236,7 +236,8 @@ class PostBuildCommands(CommandBase):
     @CommandArgument(
         'params', nargs='...',
         help="Command-line arguments to be passed through to cargo doc")
-    def doc(self, params):
+    @CommandBase.build_like_command_arguments
+    def doc(self, params, **kwargs):
         env = os.environ.copy()
         env["RUSTUP_TOOLCHAIN"] = self.toolchain()
         rustc_path = check_output(["rustup" + BIN_SUFFIX, "which", "rustc"], env=env)
@@ -264,11 +265,7 @@ class PostBuildCommands(CommandBase):
                     else:
                         copy2(full_name, destination)
 
-        params += ["--features", "azure_backend"]
-
-        returncode = self.call_rustup_run(
-            ["cargo", "doc", "--manifest-path", self.ports_glutin_manifest()] + params,
-            env=self.build_env())
+        returncode = self.run_cargo_build_like_command("doc", params, **kwargs)
         if returncode:
             return returncode
 
diff --git a/python/servo/testing_commands.py b/python/servo/testing_commands.py
index 8696f02f8dc..d1880f6385e 100644
--- a/python/servo/testing_commands.py
+++ b/python/servo/testing_commands.py
@@ -214,7 +214,8 @@ class MachCommands(CommandBase):
                      help="Run in bench mode")
     @CommandArgument('--nocapture', default=False, action="store_true",
                      help="Run tests with nocapture ( show test stdout )")
-    def test_unit(self, test_name=None, package=None, bench=False, nocapture=False):
+    @CommandBase.build_like_command_arguments
+    def test_unit(self, test_name=None, package=None, bench=False, nocapture=False, **kwargs):
         if test_name is None:
             test_name = []
 
@@ -277,22 +278,18 @@ class MachCommands(CommandBase):
             # in to the servo.exe build dir, so just point PATH to that.
             env["PATH"] = "%s%s%s" % (path.dirname(self.get_binary_path(False, False)), os.pathsep, env["PATH"])
 
-        features = self.servo_features()
         if len(packages) > 0 or len(in_crate_packages) > 0:
-            args = ["cargo", "bench" if bench else "test", "--manifest-path", self.ports_glutin_manifest()]
+            args = []
             for crate in packages:
                 args += ["-p", "%s_tests" % crate]
             for crate in in_crate_packages:
                 args += ["-p", crate]
             args += test_patterns
 
-            if features:
-                args += ["--features", "%s" % ' '.join(features)]
-
             if nocapture:
                 args += ["--", "--nocapture"]
 
-            err = self.call_rustup_run(args, env=env)
+            err = self.run_cargo_build_like_command("bench" if bench else "test", args, env=env, **kwargs)
             if err is not 0:
                 return err