Add future-incompat as an alias for future-incompatibilities.

src/bin/cargo/commands/report.rs

@@ -10,6 +10,7 @@ pub fn cli() -> App {
         .setting(clap::AppSettings::SubcommandRequiredElseHelp)
         .subcommand(
             subcommand("future-incompatibilities")
+                .alias("future-incompat")
                 .about("Reports any crates which will eventually stop compiling")
                 .arg(
                     opt(

tests/testsuite/future_incompat_report.rs

@@ -190,7 +190,7 @@ fn test_multi_crate() {
 
     // Test without --id, and also the full output of the report.
     let output = p
-        .cargo("report future-incompatibilities -Z future-incompat-report")
+        .cargo("report future-incompat -Z future-incompat-report")
         .masquerade_as_nightly_cargo()
         .exec_with_output()
         .unwrap();