apply suggestions

src/cargo/core/resolver/features.rs

@@ -45,7 +45,7 @@ use crate::core::resolver::{Resolve, ResolveBehavior};
 use crate::core::{FeatureValue, PackageId, PackageIdSpec, PackageSet, Workspace};
 use crate::util::interning::InternedString;
 use crate::util::CargoResult;
-use anyhow::bail;
+use anyhow::{bail, Context};
 use itertools::Itertools;
 use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
 use std::rc::Rc;
@@ -871,8 +871,11 @@ impl<'a, 'cfg> FeatureResolver<'a, 'cfg> {
                                 // not all targets may be queried before resolution since artifact dependencies
                                 // and per-pkg-targets are not immediately known.
                                 let mut activate_target = |target| {
+                                    let name = dep.name_in_toml();
                                     self.target_data
                                         .merge_compile_kind(CompileKind::Target(target))
+                                        .with_context(|| format!("failed to determine target information for target `{target}`.\n  \
+                                        Artifact dependency `{name}` in package `{pkg_id}` requires building for `{target}`", target = target.rustc_target()))
                                 };
                                 CargoResult::Ok((
                                     artifact.is_lib(),

src/cargo/sources/registry/index.rs

@@ -178,7 +178,7 @@ struct Summaries {
 /// A lazily parsed [`IndexSummary`].
 enum MaybeIndexSummary {
     /// A summary which has not been parsed, The `start` and `end` are pointers
-    /// into [`Summaries::raw_data`] which this isRegistryDependency an entry of.
+    /// into [`Summaries::raw_data`] which this is an entry of.
     Unparsed { start: usize, end: usize },
 
     /// An actually parsed summary.
@@ -313,6 +313,9 @@ pub struct IndexPackage<'a> {
     ///
     /// Version `2` schema adds the `features2` field.
     ///
+    /// Version `3` schema adds `artifact`, `bindep_targes`, and `lib` for
+    /// artifact dependencies support.
+    ///
     /// This provides a method to safely introduce changes to index entries
     /// and allow older versions of cargo to ignore newer entries it doesn't
     /// understand. This is honored as of 1.51, so unfortunately older
@@ -821,7 +824,7 @@ impl<'a> SummariesCache<'a> {
             .get(..4)
             .ok_or_else(|| anyhow::anyhow!("cache expected 4 bytes for index schema version"))?;
         let index_v = u32::from_le_bytes(index_v_bytes.try_into().unwrap());
-        if index_v != INDEX_V_MAX && index_v != 3 {
+        if index_v != INDEX_V_MAX {
             bail!(
                 "index schema version {index_v} doesn't match the version I know ({INDEX_V_MAX})",
             );

tests/testsuite/artifact_dep.rs

@@ -1458,6 +1458,7 @@ fn targets_are_picked_up_from_non_workspace_artifact_deps() {
 
     let mut dep = registry::Dependency::new("artifact", "1.0.0");
     Package::new("uses-artifact", "1.0.0")
+        .schema_version(3)
         .file(
             "src/lib.rs",
             r#"pub fn uses_artifact() { let _b = include_bytes!(env!("CARGO_BIN_FILE_ARTIFACT")); }"#,
@@ -1489,6 +1490,127 @@ fn targets_are_picked_up_from_non_workspace_artifact_deps() {
         .run();
 }
 
+#[cargo_test]
+fn index_version_filtering() {
+    if cross_compile::disabled() {
+        return;
+    }
+    let target = cross_compile::alternate();
+
+    Package::new("artifact", "1.0.0")
+        .file("src/main.rs", r#"fn main() {}"#)
+        .file("src/lib.rs", r#"pub fn lib() {}"#)
+        .publish();
+
+    let mut dep = registry::Dependency::new("artifact", "1.0.0");
+
+    Package::new("bar", "1.0.0").publish();
+    Package::new("bar", "1.0.1")
+        .schema_version(3)
+        .add_dep(dep.artifact("bin", Some(target.to_string())))
+        .publish();
+
+    // Verify that without `-Zbindeps` that it does not use 1.0.1.
+    let p = project()
+        .file(
+            "Cargo.toml",
+            r#"
+                [package]
+                name = "foo"
+                version = "0.1.0"
+
+                [dependencies]
+                bar = "1.0"
+            "#,
+        )
+        .file("src/lib.rs", "")
+        .build();
+
+    p.cargo("tree")
+        .with_stdout("foo v0.1.0 [..]\n└── bar v1.0.0")
+        .run();
+
+    // And with -Zbindeps it can use 1.0.1.
+    p.cargo("update -Zbindeps")
+        .masquerade_as_nightly_cargo(&["bindeps"])
+        .with_stderr(
+            "\
+[UPDATING] [..]
+[ADDING] artifact v1.0.0
+[UPDATING] bar v1.0.0 -> v1.0.1",
+        )
+        .run();
+
+    // And without -Zbindeps, now that 1.0.1 is in Cargo.lock, it should fail.
+    p.cargo("check")
+        .with_status(101)
+        .with_stderr(
+            "\
+[UPDATING] [..]
+error: failed to select a version for the requirement `bar = \"^1.0\"` (locked to 1.0.1)
+candidate versions found which didn't match: 1.0.0
+location searched: [..]
+required by package `foo v0.1.0 [..]`
+perhaps a crate was updated and forgotten to be re-vendored?",
+        )
+        .run();
+}
+
+// FIXME: `download_accessible` should work properly for artifact dependencies
+#[cargo_test]
+#[ignore = "broken, needs download_accessible fix"]
+fn proc_macro_in_artifact_dep() {
+    // Forcing FeatureResolver to check a proc-macro for a dependency behind a
+    // target dependency.
+    if cross_compile::disabled() {
+        return;
+    }
+    Package::new("pm", "1.0.0")
+        .file("src/lib.rs", "")
+        .file(
+            "Cargo.toml",
+            r#"
+                [package]
+                name = "pm"
+                version = "1.0.0"
+
+                [lib]
+                proc-macro = true
+
+            "#,
+        )
+        .publish();
+    let alternate = cross_compile::alternate();
+    Package::new("bin-uses-pm", "1.0.0")
+        .target_dep("pm", "1.0", alternate)
+        .file("src/main.rs", "fn main() {}")
+        .publish();
+    // Simulate a network error downloading the proc-macro.
+    std::fs::remove_file(cargo_test_support::paths::root().join("dl/pm/1.0.0/download")).unwrap();
+    let p = project()
+        .file(
+            "Cargo.toml",
+            &format!(
+                r#"
+                [package]
+                name = "foo"
+                version = "0.1.0"
+                edition = "2021"
+
+                [dependencies]
+                bin-uses-pm = {{ version = "1.0", artifact = "bin", target = "{alternate}"}}
+            "#
+            ),
+        )
+        .file("src/lib.rs", "")
+        .build();
+
+    p.cargo("check -Z bindeps")
+        .masquerade_as_nightly_cargo(&["bindeps"])
+        .with_stderr("")
+        .run();
+}
+
 #[cargo_test]
 fn allow_dep_renames_with_multiple_versions() {
     Package::new("bar", "1.0.0")
@@ -2896,7 +3018,8 @@ fn check_transitive_artifact_dependency_with_different_target() {
     p.cargo("check -Z bindeps")
         .masquerade_as_nightly_cargo(&["bindeps"])
         .with_stderr_contains(
-            "error: failed to run `rustc` to learn about target-specific information",
+            "error: failed to determine target information for target `custom-target`.\n  \
+            Artifact dependency `baz` in package `bar v0.0.0 [..]` requires building for `custom-target`",
         )
         .with_status(101)
         .run();