check subcommand should force rebuild

src/bin/cargo/commands/check.rs

@@ -26,6 +26,7 @@ pub fn cli() -> App {
             "Check all targets",
         )
         .arg_release("Check artifacts in release mode, with optimizations")
+        .arg_force_rebuild("Force rebuild of this crate")
         .arg(opt("profile", "Profile to build the selected target for").value_name("PROFILE"))
         .arg_features()
         .arg_target_triple("Check for the target triple")

src/cargo/util/command_prelude.rs

@@ -185,6 +185,10 @@ pub trait AppExt: Sized {
     fn arg_dry_run(self, dry_run: &'static str) -> Self {
         self._arg(opt("dry-run", dry_run))
     }
+
+    fn arg_force_rebuild(self, force_rebuild: &'static str) -> Self {
+        self._arg(opt("force-rebuild", force_rebuild))
+    }
 }
 
 impl AppExt for App {
@@ -315,6 +319,7 @@ pub trait ArgMatchesExt {
         build_config.message_format = message_format;
         build_config.release = self._is_present("release");
         build_config.build_plan = self._is_present("build-plan");
+        build_config.force_rebuild = self._is_present("force-rebuild");
         if build_config.build_plan && !config.cli_unstable().unstable_options {
             Err(failure::format_err!(
                 "`--build-plan` flag is unstable, pass `-Z unstable-options` to enable it"

tests/testsuite/check.rs

@@ -195,6 +195,26 @@ fn build_check() {
     foo.cargo("check").run();
 }
 
+// Checks that --force-rebuild displays warnings even if the project has not changed
+//     since the last check/build
+#[test]
+fn force_rebuild_displays_error() {
+    let foo = project()
+        .file(
+            "src/main.rs",
+            "use std::default::Default; fn main() {}",
+        )
+        .build();
+
+    foo.cargo("check")
+        .with_stderr_contains("[..]warning: unused import[..]")
+        .run();
+
+    foo.cargo("check --force-rebuild")
+        .with_stderr_contains("[..]warning: unused import[..]")
+        .run();
+}
+
 // Checks that where a project has both a lib and a bin, the lib is only checked
 // not built.
 #[test]

tests/testsuite/profile_targets.rs

@@ -1,4 +1,3 @@
-use crate::support::is_nightly;
 use crate::support::{basic_manifest, project, Project};
 
 // These tests try to exercise exactly which profiles are selected for every
@@ -454,11 +453,6 @@ fn profile_selection_bench() {
 
 #[test]
 fn profile_selection_check_all_targets() {
-    if !is_nightly() {
-        // This can be removed once 1.27 is stable, see below.
-        return;
-    }
-
     let p = all_target_project();
     // check
     // NOTES:
@@ -525,11 +519,6 @@ fn profile_selection_check_all_targets() {
 
 #[test]
 fn profile_selection_check_all_targets_release() {
-    if !is_nightly() {
-        // See note in profile_selection_check_all_targets.
-        return;
-    }
-
     let p = all_target_project();
     // check --release
     // https://github.com/rust-lang/cargo/issues/5218
@@ -572,11 +561,6 @@ fn profile_selection_check_all_targets_release() {
 
 #[test]
 fn profile_selection_check_all_targets_test() {
-    if !is_nightly() {
-        // See note in profile_selection_check_all_targets.
-        return;
-    }
-
     let p = all_target_project();
     // check --profile=test
     // NOTES: