test(feature-metadata): test valid and invalid feature metadata

Author: AudaciousAxiom

tests/testsuite/features.rs

@@ -1,6 +1,9 @@
 //! Tests for `[features]` table.
 
+use std::fs::File;
+
 use cargo_test_support::prelude::*;
+use cargo_test_support::publish::validate_crate_contents;
 use cargo_test_support::registry::{Dependency, Package};
 use cargo_test_support::str;
 use cargo_test_support::{basic_manifest, project};
@@ -2282,3 +2285,173 @@ fn invalid_feature_name_slash_error() {
 "#]])
         .run();
 }
+
+#[cargo_test]
+fn feature_metadata() {
+    let p = project()
+        .file(
+            "Cargo.toml",
+            r#"
+                [package]
+                name = "foo"
+                edition = "2015"
+
+                [features]
+                a = []
+                b = []
+                c = { enables = ["a", "b"] }
+            "#,
+        )
+        .file(
+            "src/main.rs",
+            r#"
+                #[cfg(feature = "a")]
+                fn a() {}
+                #[cfg(feature = "b")]
+                fn b() {}
+                fn main() {
+                    a();
+                    b();
+                }
+            "#,
+        )
+        .build();
+
+    p.cargo("check --features c").run();
+}
+
+#[cargo_test]
+fn feature_metadata_missing_enables() {
+    let p = project()
+        .file(
+            "Cargo.toml",
+            r#"
+                [package]
+                name = "foo"
+                edition = "2015"
+
+                [features]
+                foo = {}
+            "#,
+        )
+        .file("src/lib.rs", "")
+        .build();
+
+    p.cargo("check")
+        .with_status(101)
+        .with_stderr_data(str![[r#"
+[ERROR] missing field `enables`
+ --> Cargo.toml:7:23
+  |
+7 |                 foo = {}
+  |                       ^^
+  |
+
+"#]])
+        .run();
+}
+
+#[cargo_test]
+fn unused_keys_in_feature_metadata() {
+    let p = project()
+        .file(
+            "Cargo.toml",
+            r#"
+               [package]
+               name = "foo"
+               edition = "2015"
+
+               [features]
+               foo = { enables = ["bar"], foobar = false }
+               bar = []
+            "#,
+        )
+        .file("src/lib.rs", "")
+        .build();
+
+    p.cargo("check")
+        .with_stderr_data(str![[r#"
+[WARNING] unused manifest key: `features.foo.foobar`
+[CHECKING] foo v0.0.0 ([ROOT]/foo)
+[FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
+
+"#]])
+        .run();
+}
+
+#[cargo_test]
+fn normalize_feature_metadata() {
+    let p = project()
+        .file(
+            "Cargo.toml",
+            r#"
+                [package]
+                name = "foo"
+                edition = "2015"
+
+                [features]
+                a = []
+                b = []
+                c = { enables = ["a", "b"] }
+            "#,
+        )
+        .file(
+            "src/main.rs",
+            r#"
+                #[cfg(feature = "a")]
+                fn a() {}
+                #[cfg(feature = "b")]
+                fn b() {}
+                fn main() {
+                    a();
+                    b();
+                }
+            "#,
+        )
+        .build();
+
+    p.cargo("package --no-verify -v").run();
+    let f = File::open(&p.root().join("target/package/foo-0.0.0.crate")).unwrap();
+    let normalized_manifest = str![[r#"
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2015"
+name = "foo"
+build = false
+autolib = false
+autobins = false
+autoexamples = false
+autotests = false
+autobenches = false
+readme = false
+
+[features]
+a = []
+b = []
+c = [
+    "a",
+    "b",
+]
+
+[[bin]]
+name = "foo"
+path = "src/main.rs"
+
+"#]];
+    validate_crate_contents(
+        f,
+        "foo-0.0.0.crate",
+        &["Cargo.lock", "Cargo.toml", "Cargo.toml.orig", "src/main.rs"],
+        [("Cargo.toml", normalized_manifest)],
+    );
+}