Add -Zbuild-std test

.github/workflows/rust.yml

@@ -60,3 +60,28 @@ jobs:
       run: cargo test --verbose
     - name: Test no-rustc mode
       run: cargo check --no-default-features
+
+  build-std:
+    strategy:
+      matrix:
+        include:
+          - os: ubuntu-latest
+            host_target: x86_64-unknown-linux-gnu
+          - os: macos-latest
+            host_target: x86_64-apple-darwin
+          - os: windows-latest
+            host_target: i686-pc-windows-msvc
+    runs-on: ${{ matrix.os }}
+    # Run tests under a directory with a space in it to double check the windows path heuristic
+    defaults:
+      run:
+        working-directory: "dir with spaces/build std"
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        path: "dir with spaces/build std"
+    - uses: dtolnay/rust-toolchain@nightly
+      with:
+        components: rust-src
+    - name: Run build-std test
+      run: cargo test --verbose --test build_std

Cargo.toml

@@ -45,6 +45,10 @@ features = ["capture-spantrace"]
 name = "integration"
 harness = false
 
+[[test]]
+name = "build_std"
+test = false
+
 [features]
 default = ["rustc"]
 rustc = []

tests/build_std.rs

@@ -0,0 +1,21 @@
+use ui_test::dependencies::DependencyBuilder;
+use ui_test::spanned::Spanned;
+use ui_test::Config;
+
+#[test]
+fn test() {
+    let mut config = Config::rustc("tests/build_std");
+    let revisioned = config.comment_defaults.base();
+
+    revisioned.exit_status = Spanned::dummy(0).into();
+    revisioned.require_annotations = Spanned::dummy(false).into();
+    revisioned.set_custom(
+        "dependencies",
+        DependencyBuilder {
+            build_std: Some(String::new()),
+            ..DependencyBuilder::default()
+        },
+    );
+
+    ui_test::run_tests(config).unwrap();
+}