fix(fingerprint): include bin target if it is also an artifact dep

src/cargo/core/compiler/fingerprint.rs

@@ -1254,20 +1254,24 @@ fn calculate(cx: &mut Context<'_, '_>, unit: &Unit) -> CargoResult<Arc<Fingerpri
 /// Calculate a fingerprint for a "normal" unit, or anything that's not a build
 /// script. This is an internal helper of `calculate`, don't call directly.
 fn calculate_normal(cx: &mut Context<'_, '_>, unit: &Unit) -> CargoResult<Fingerprint> {
-    // Recursively calculate the fingerprint for all of our dependencies.
-    //
-    // Skip fingerprints of binaries because they don't actually induce a
-    // recompile, they're just dependencies in the sense that they need to be
-    // built.
-    //
-    // Create Vec since mutable cx is needed in closure.
-    let deps = Vec::from(cx.unit_deps(unit));
-    let mut deps = deps
-        .into_iter()
-        .filter(|dep| !dep.unit.target.is_bin())
-        .map(|dep| DepFingerprint::new(cx, unit, &dep))
-        .collect::<CargoResult<Vec<_>>>()?;
-    deps.sort_by(|a, b| a.pkg_id.cmp(&b.pkg_id));
+    let deps = {
+        // Recursively calculate the fingerprint for all of our dependencies.
+        //
+        // Skip fingerprints of binaries because they don't actually induce a
+        // recompile, they're just dependencies in the sense that they need to be
+        // built. The only exception here are artifact dependencies,
+        // which is an actual dependency that needs a recompile.
+        //
+        // Create Vec since mutable cx is needed in closure.
+        let deps = Vec::from(cx.unit_deps(unit));
+        let mut deps = deps
+            .into_iter()
+            .filter(|dep| !dep.unit.target.is_bin() || dep.unit.artifact.is_true())
+            .map(|dep| DepFingerprint::new(cx, unit, &dep))
+            .collect::<CargoResult<Vec<_>>>()?;
+        deps.sort_by(|a, b| a.pkg_id.cmp(&b.pkg_id));
+        deps
+    };
 
     // Afterwards calculate our own fingerprint information.
     let target_root = target_root(cx);

tests/testsuite/artifact_dep.rs

@@ -2279,7 +2279,7 @@ fn build_script_features_for_shared_dependency() {
 
 #[cargo_test]
 fn calc_bin_artifact_fingerprint() {
-    // This records the WRONG behaviour. See rust-lang/cargo#10527
+    // See rust-lang/cargo#10527
     let p = project()
         .file(
             "Cargo.toml",
@@ -2316,29 +2316,27 @@ fn calc_bin_artifact_fingerprint() {
         .run();
 
     p.change_file("bar/src/main.rs", r#"fn main() { println!("bar") }"#);
-    // Change in bin artifact but not propagated to parent fingerprint.
-    // This is WRONG!
+    // Change in artifact bin dep `bar` propagates to `foo`, triggering recompile.
     p.cargo("check -v -Z bindeps")
         .masquerade_as_nightly_cargo(&["bindeps"])
         .with_stderr(
             "\
 [COMPILING] bar v0.5.0 ([CWD]/bar)
 [RUNNING] `rustc --crate-name bar [..]`
-[FRESH] foo v0.1.0 ([CWD])
+[CHECKING] foo v0.1.0 ([CWD])
+[RUNNING] `rustc --crate-name foo [..]`
 [FINISHED] dev [unoptimized + debuginfo] target(s) in [..]
 ",
         )
         .run();
 
-    // Only run the second time can parent fingerpint perceive the change.
-    // This is WRONG!
+    // All units are fresh. No recompile.
     p.cargo("check -v -Z bindeps")
         .masquerade_as_nightly_cargo(&["bindeps"])
         .with_stderr(
             "\
 [FRESH] bar v0.5.0 ([CWD]/bar)
-[CHECKING] foo v0.1.0 ([CWD])
-[RUNNING] `rustc --crate-name foo [..]`
+[FRESH] foo v0.1.0 ([CWD])
 [FINISHED] dev [unoptimized + debuginfo] target(s) in [..]
 ",
         )