Expose test-float-parse via bootstrap

With updates to `test-float-parse`, it is now possible to run as another
Rust tool. Enable check, clippy, and test.

Test runs the unit tests, as well as shorter parsing tests (takes
approximately 1 minute).

src/bootstrap/src/core/build_steps/check.rs

@@ -466,6 +466,7 @@ tool_check_step!(CargoMiri, "src/tools/miri/cargo-miri", SourceType::InTree);
 tool_check_step!(Rls, "src/tools/rls", SourceType::InTree);
 tool_check_step!(Rustfmt, "src/tools/rustfmt", SourceType::InTree);
 tool_check_step!(MiroptTestTools, "src/tools/miropt-test-tools", SourceType::InTree);
+tool_check_step!(TestFloatParse, "src/etc/test-float-parse", SourceType::InTree);
 
 tool_check_step!(Bootstrap, "src/bootstrap", SourceType::InTree, false);
 

src/bootstrap/src/core/build_steps/clippy.rs

@@ -326,4 +326,5 @@ lint_any!(
     Rustfmt, "src/tools/rustfmt", "rustfmt";
     RustInstaller, "src/tools/rust-installer", "rust-installer";
     Tidy, "src/tools/tidy", "tidy";
+    TestFloatParse, "src/etc/test-float-parse", "test-float-parse";
 );

src/bootstrap/src/core/build_steps/test.rs

@@ -3505,3 +3505,80 @@ impl Step for CodegenGCC {
         cargo.into_cmd().run(builder);
     }
 }
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TestFloatParse {
+    path: PathBuf,
+    host: TargetSelection,
+}
+
+impl Step for TestFloatParse {
+    type Output = ();
+    const ONLY_HOSTS: bool = true;
+    const DEFAULT: bool = true;
+
+    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
+        run.path("src/etc/test-float-parse")
+    }
+
+    fn make_run(run: RunConfig<'_>) {
+        for path in run.paths {
+            let path = path.assert_single_path().path.clone();
+            run.builder.ensure(Self { path, host: run.target });
+        }
+    }
+
+    fn run(self, builder: &Builder<'_>) {
+        let bootstrap_host = builder.config.build;
+        let compiler = builder.compiler(0, bootstrap_host);
+        let path = self.path.to_str().unwrap();
+        let crate_name = self.path.components().last().unwrap().as_os_str().to_str().unwrap();
+
+        builder.ensure(compile::Std::new(compiler, self.host));
+
+        // Run any unit tests in the crate
+        let cargo_test = tool::prepare_tool_cargo(
+            builder,
+            compiler,
+            Mode::ToolStd,
+            bootstrap_host,
+            "test",
+            path,
+            SourceType::InTree,
+            &[],
+        );
+
+        run_cargo_test(
+            cargo_test,
+            &[],
+            &[],
+            crate_name,
+            crate_name,
+            compiler,
+            bootstrap_host,
+            builder,
+        );
+
+        // Run the actual parse tests.
+        let mut cargo_run = tool::prepare_tool_cargo(
+            builder,
+            compiler,
+            Mode::ToolStd,
+            bootstrap_host,
+            "run",
+            path,
+            SourceType::InTree,
+            &[],
+        );
+
+        cargo_run.arg("--");
+        if builder.config.args().is_empty() {
+            // By default, exclude tests that take longer than ~1m.
+            cargo_run.arg("--skip-huge");
+        } else {
+            cargo_run.args(builder.config.args());
+        }
+
+        cargo_run.into_cmd().run(builder);
+    }
+}

src/bootstrap/src/core/builder.rs

@@ -826,6 +826,7 @@ impl<'a> Builder<'a> {
                 clippy::Rustdoc,
                 clippy::Rustfmt,
                 clippy::RustInstaller,
+                clippy::TestFloatParse,
                 clippy::Tidy,
             ),
             Kind::Check | Kind::Fix => describe!(
@@ -840,6 +841,7 @@ impl<'a> Builder<'a> {
                 check::Rls,
                 check::Rustfmt,
                 check::RustAnalyzer,
+                check::TestFloatParse,
                 check::Bootstrap,
             ),
             Kind::Test => describe!(
@@ -901,6 +903,7 @@ impl<'a> Builder<'a> {
                 test::RustdocJson,
                 test::HtmlCheck,
                 test::RustInstaller,
+                test::TestFloatParse,
                 // Run bootstrap close to the end as it's unlikely to fail
                 test::Bootstrap,
                 // Run run-make last, since these won't pass without make on Windows