1 files changed, 57 insertions, 0 deletions
diff --git a/compiler/rustc_target/src/tests.rs b/compiler/rustc_target/src/tests.rs
new file mode 100644
index 000000000..76375170d
--- /dev/null
+++ b/compiler/rustc_target/src/tests.rs
@@ -0,0 +1,57 @@
+use crate::spec::Target;
+
+#[test]
+fn report_unused_fields() {
+    let json = serde_json::from_str(
+        r#"
+    {
+        "arch": "powerpc64",
+        "data-layout": "e-m:e-i64:64-n32:64",
+        "llvm-target": "powerpc64le-elf",
+        "target-pointer-width": "64",
+        "code-mode": "foo"
+    }
+    "#,
+    )
+    .unwrap();
+    let warnings = Target::from_json(json).unwrap().1;
+    assert_eq!(warnings.warning_messages().len(), 1);
+    assert!(warnings.warning_messages().join("\n").contains("code-mode"));
+}
+
+#[test]
+fn report_incorrect_json_type() {
+    let json = serde_json::from_str(
+        r#"
+    {
+        "arch": "powerpc64",
+        "data-layout": "e-m:e-i64:64-n32:64",
+        "llvm-target": "powerpc64le-elf",
+        "target-pointer-width": "64",
+        "link-env-remove": "foo"
+    }
+    "#,
+    )
+    .unwrap();
+    let warnings = Target::from_json(json).unwrap().1;
+    assert_eq!(warnings.warning_messages().len(), 1);
+    assert!(warnings.warning_messages().join("\n").contains("link-env-remove"));
+}
+
+#[test]
+fn no_warnings_for_valid_target() {
+    let json = serde_json::from_str(
+        r#"
+    {
+        "arch": "powerpc64",
+        "data-layout": "e-m:e-i64:64-n32:64",
+        "llvm-target": "powerpc64le-elf",
+        "target-pointer-width": "64",
+        "link-env-remove": ["foo"]
+    }
+    "#,
+    )
+    .unwrap();
+    let warnings = Target::from_json(json).unwrap().1;
+    assert_eq!(warnings.warning_messages().len(), 0);
+}