Auto merge of #6500 - ehuss:metadata-reg, r=alexcrichton

Add dependency `registry` to `cargo metadata`.

This adds the `registry` field for dependencies for alternate registries in
`cargo metadata`.

Cargo.toml

@@ -19,6 +19,7 @@ path = "src/cargo/lib.rs"
 
 [dependencies]
 atty = "0.2"
+byteorder = "1.2"
 bytesize = "1.0"
 crates-io = { path = "src/crates-io", version = "0.22" }
 crossbeam-utils = "0.6"
@@ -57,6 +58,7 @@ tempfile = "3.0"
 termcolor = "1.0"
 toml = "0.4.2"
 url = "1.1"
+url_serde = "0.2.0"
 clap = "2.31.2"
 unicode-width = "0.1.5"
 openssl = { version = '0.10.11', optional = true }

src/cargo/core/dependency.rs

@@ -7,6 +7,7 @@ use semver::ReqParseError;
 use semver::VersionReq;
 use serde::ser;
 use serde::Serialize;
+use url::Url;
 
 use crate::core::interning::InternedString;
 use crate::core::{PackageId, SourceId, Summary};
@@ -25,6 +26,12 @@ pub struct Dependency {
 struct Inner {
     name: InternedString,
     source_id: SourceId,
+    /// Source ID for the registry as specified in the manifest.
+    ///
+    /// This will be None if it is not specified (crates.io dependency).
+    /// This is different from `source_id` for example when both a `path` and
+    /// `registry` is specified. Or in the case of a crates.io dependency,
+    /// `source_id` will be crates.io and this will be None.
     registry_id: Option<SourceId>,
     req: VersionReq,
     specified_req: bool,
@@ -59,6 +66,10 @@ struct SerializedDependency<'a> {
     uses_default_features: bool,
     features: &'a [InternedString],
     target: Option<&'a Platform>,
+    /// The registry URL this dependency is from.
+    /// If None, then it comes from the default registry (crates.io).
+    #[serde(with = "url_serde")]
+    registry: Option<Url>,
 }
 
 impl ser::Serialize for Dependency {
@@ -76,6 +87,7 @@ impl ser::Serialize for Dependency {
             features: self.features(),
             target: self.platform(),
             rename: self.explicit_name_in_toml().map(|s| s.as_str()),
+            registry: self.registry_id().map(|sid| sid.url().clone()),
         }
         .serialize(s)
     }

src/cargo/core/source/source_id.rs

@@ -40,6 +40,8 @@ struct SourceIdInner {
     // e.g. the exact git revision of the specified branch for a Git Source
     precise: Option<String>,
     /// Name of the registry source for alternative registries
+    /// WARNING: This is not always set for alt-registries when the name is
+    /// not known.
     name: Option<String>,
 }
 
@@ -247,6 +249,8 @@ impl SourceId {
     }
 
     /// Is this source from an alternative registry
+    /// DEPRECATED: This is not correct if the registry name is not known
+    /// (for example when loaded from an index).
     pub fn is_alt_registry(self) -> bool {
         self.is_registry() && self.inner.name.is_some()
     }

src/cargo/ops/registry.rs

@@ -159,8 +159,10 @@ fn transmit(
             // registry in the dependency.
             let dep_registry_id = match dep.registry_id() {
                 Some(id) => id,
-                None => failure::bail!("dependency missing registry ID"),
+                None => SourceId::crates_io(config)?,
             };
+            // In the index and Web API, None means "from the same registry"
+            // whereas in Cargo.toml, it means "from crates.io".
             let dep_registry = if dep_registry_id != registry_id {
                 Some(dep_registry_id.url().to_string())
             } else {

src/cargo/sources/registry/mod.rs

@@ -299,7 +299,7 @@ impl<'a> RegistryDependency<'a> {
             package,
         } = self;
 
-        let id = if let Some(registry) = registry {
+        let id = if let Some(registry) = &registry {
             SourceId::for_registry(&registry.to_url()?)?
         } else {
             default
@@ -328,6 +328,12 @@ impl<'a> RegistryDependency<'a> {
         // out here.
         features.retain(|s| !s.is_empty());
 
+        // In index, "registry" is null if it is from the same index.
+        // In Cargo.toml, "registry" is None if it is from the default
+        if !id.is_default_registry() {
+            dep.set_registry_id(id);
+        }
+
         dep.set_optional(optional)
             .set_default_features(default_features)
             .set_features(features)
@@ -486,22 +492,7 @@ impl<'cfg> RegistrySource<'cfg> {
             MaybePackage::Ready(pkg) => pkg,
             MaybePackage::Download { .. } => unreachable!(),
         };
-
-        // Unfortunately the index and the actual Cargo.toml in the index can
-        // differ due to historical Cargo bugs. To paper over these we trash the
-        // *summary* loaded from the Cargo.toml we just downloaded with the one
-        // we loaded from the index.
-        let summaries = self
-            .index
-            .summaries(package.name().as_str(), &mut *self.ops)?;
-        let summary = summaries
-            .iter()
-            .map(|s| &s.0)
-            .find(|s| s.package_id() == package)
-            .expect("summary not found");
-        let mut manifest = pkg.manifest().clone();
-        manifest.set_summary(summary.clone());
-        Ok(Package::new(manifest, pkg.manifest_path()))
+        Ok(pkg)
     }
 }
 

src/cargo/util/toml/mod.rs

@@ -201,6 +201,12 @@ impl<'de> de::Deserialize<'de> for TomlDependency {
 pub struct DetailedTomlDependency {
     version: Option<String>,
     registry: Option<String>,
+    /// The URL of the `registry` field.
+    /// This is an internal implementation detail. When Cargo creates a
+    /// package, it replaces `registry` with `registry-index` so that the
+    /// manifest contains the correct URL. All users won't have the same
+    /// registry names configured, so Cargo can't rely on just the name for
+    /// crates published by other users.
     registry_index: Option<String>,
     path: Option<String>,
     git: Option<String>,
@@ -1307,14 +1313,6 @@ impl DetailedTomlDependency {
             }
         }
 
-        let registry_id = match self.registry {
-            Some(ref registry) => {
-                cx.features.require(Feature::alternative_registries())?;
-                SourceId::alt_registry(cx.config, registry)?
-            }
-            None => SourceId::crates_io(cx.config)?,
-        };
-
         let new_source_id = match (
             self.git.as_ref(),
             self.path.as_ref(),
@@ -1410,8 +1408,19 @@ impl DetailedTomlDependency {
                     .unwrap_or(true),
             )
             .set_optional(self.optional.unwrap_or(false))
-            .set_platform(cx.platform.clone())
-            .set_registry_id(registry_id);
+            .set_platform(cx.platform.clone());
+        if let Some(registry) = &self.registry {
+            cx.features.require(Feature::alternative_registries())?;
+            let registry_id = SourceId::alt_registry(cx.config, registry)?;
+            dep.set_registry_id(registry_id);
+        }
+        if let Some(registry_index) = &self.registry_index {
+            cx.features.require(Feature::alternative_registries())?;
+            let url = registry_index.to_url()?;
+            let registry_id = SourceId::for_registry(&url)?;
+            dep.set_registry_id(registry_id);
+        }
+
         if let Some(kind) = kind {
             dep.set_kind(kind);
         }

src/doc/man/cargo-metadata.adoc

@@ -61,7 +61,9 @@ The output has the following format:
                 {
                     /* The name of the dependency. */
                     "name": "bitflags",
-                    /* The source ID of the dependency. */
+                    /* The source ID of the dependency. May be null, see
+                       description for the package source.
+                    */
                     "source": "registry+https://github.com/rust-lang/crates.io-index",
                     /* The version requirement for the dependency.
                        Dependencies without a version requirement have a value of "*".
@@ -84,7 +86,12 @@ The output has the following format:
                     /* The target platform for the dependency.
                        null if not a target dependency.
                     */
-                    "target": "cfg(windows)"
+                    "target": "cfg(windows)",
+                    /* A string of the URL of the registry this dependency is from.
+                       If not specified or null, the dependency is from the default
+                       registry (crates.io).
+                    */
+                    "registry": null
                 }
             ],
             /* Array of Cargo targets. */