Ensure metadata of self-referential crates can be read. (#1035)

Also ensure that if reading metadata fails, we don't crash and instead
just avoid checking manifest-related lints.

Cargo.toml

@@ -18,8 +18,8 @@ exclude = [".github/", "brand/", "scripts/", "test_crates/", "test_outputs/", "t
 trustfall = "0.8.0"
 # `cargo_metadata` is used at the API boundary of `trustfall_rustdoc`,
 # so ensure the version we use for `cargo_metadata` here matches what `trustfall_rustdoc` uses too.
-trustfall_rustdoc = { version = "0.18.1", default-features = false, features = ["v32", "v33", "v35", "v36", "v37", "rayon", "rustc-hash"] }
-cargo_metadata = "0.18.1"
+trustfall_rustdoc = { version = "0.19.0", default-features = false, features = ["v32", "v33", "v35", "v36", "v37", "rayon", "rustc-hash"] }
+cargo_metadata = "0.19.1"
 # End of dependency block
 
 clap = { version = "4.5.21", features = ["derive", "cargo"] }

src/lib.rs

@@ -243,10 +243,15 @@ impl Scope {
 /// semver-check rlib, dylib, and staticlib targets as well.
 fn is_lib_like_checkable_target(target: &cargo_metadata::Target) -> bool {
     target.is_lib()
-        || target
-            .kind
-            .iter()
-            .any(|kind| matches!(kind.as_str(), "rlib" | "dylib" | "staticlib"))
+        || target.kind.iter().any(|kind| {
+            matches!(
+                kind,
+                cargo_metadata::TargetKind::RLib { .. }
+                    | cargo_metadata::TargetKind::DyLib { .. }
+                    | cargo_metadata::TargetKind::CDyLib { .. }
+                    | cargo_metadata::TargetKind::StaticLib { .. }
+            )
+        })
 }
 
 impl Check {

src/snapshot_tests.rs

@@ -402,6 +402,29 @@ fn multiple_ambiguous_package_name_definitions() {
     );
 }
 
+/// Ensure that linting self-referential packages (usually used for the "SemVer trick")
+/// works properly and doesn't suffer any issues due to the self-referential metadata.
+///
+/// More info on the "SemVer trick": https://github.com/dtolnay/semver-trick
+///
+/// This test currently triggers the `struct_missing` lint as a false-positive,
+/// due to the cross-crate re-export. This should be fixed when we start supporting
+/// cross-crate items.
+#[test]
+fn semver_trick_self_referential() {
+    assert_integration_test(
+        "semver_trick_self_referential",
+        &[
+            "cargo",
+            "semver-checks",
+            "--baseline-root",
+            "test_crates/semver_trick_self_referential/old/",
+            "--manifest-path",
+            "test_crates/semver_trick_self_referential/new/",
+        ],
+    );
+}
+
 /// Helper function which lists all files in the directory recursively.
 ///
 /// # Arguments

test_crates/semver_trick_self_referential/future/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "semver_trick_self_referential"
+version = "0.2.0"
+edition = "2021"
+
+[dependencies]

test_crates/semver_trick_self_referential/future/src/lib.rs

@@ -0,0 +1 @@
+pub struct Example;

test_crates/semver_trick_self_referential/new/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+publish = false
+name = "semver_trick_self_referential"
+version = "0.1.1"
+edition = "2021"
+
+[dependencies]
+# The "SemVer trick": reference a future major version of the package, and re-export its types
+# within the same *minor* version to offer a smoother upgrade process between major versions.
+self_ref = { package = "semver_trick_self_referential", path = "../future", version = "0.2.0" }

test_crates/semver_trick_self_referential/new/src/lib.rs

@@ -0,0 +1 @@
+pub use self_ref::Example;

test_crates/semver_trick_self_referential/old/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "semver_trick_self_referential"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

test_crates/semver_trick_self_referential/old/src/lib.rs

@@ -0,0 +1 @@
+pub struct Example;

test_outputs/query_execution/struct_missing.snap

@@ -1,6 +1,7 @@
 ---
 source: src/query.rs
 expression: "&query_execution_results"
+snapshot_kind: text
 ---
 {
   "./test_crates/move_item_and_reexport/": [
@@ -73,6 +74,19 @@ expression: "&query_execution_results"
       "visibility_limit": String("public"),
     },
   ],
+  "./test_crates/semver_trick_self_referential/": [
+    {
+      "name": String("Example"),
+      "path": List([
+        String("semver_trick_self_referential"),
+        String("Example"),
+      ]),
+      "span_begin_line": Uint64(1),
+      "span_filename": String("src/lib.rs"),
+      "struct_type": String("unit"),
+      "visibility_limit": String("public"),
+    },
+  ],
   "./test_crates/struct_missing/": [
     {
       "name": String("WillBeRemovedStruct"),

test_outputs/snapshot_tests/cargo_semver_checks__snapshot_tests__semver_trick_self_referential-input.snap

@@ -0,0 +1,35 @@
+---
+source: src/snapshot_tests.rs
+expression: check
+snapshot_kind: text
+---
+Check(
+  scope: Scope(
+    mode: DenyList(PackageSelection(
+      selection: DefaultMembers,
+      excluded_packages: [],
+    )),
+  ),
+  current: Rustdoc(
+    source: Root("test_crates/semver_trick_self_referential/new/"),
+  ),
+  baseline: Rustdoc(
+    source: Root("test_crates/semver_trick_self_referential/old/"),
+  ),
+  release_type: None,
+  current_feature_config: FeatureConfig(
+    features_group: Heuristic,
+    extra_features: [],
+    is_baseline: false,
+  ),
+  baseline_feature_config: FeatureConfig(
+    features_group: Heuristic,
+    extra_features: [],
+    is_baseline: true,
+  ),
+  build_target: None,
+  witness_generation: WitnessGeneration(
+    show_hints: false,
+    witness_directory: None,
+  ),
+)