Implement workspaces in Cargo

This commit is an implementation of [RFC 1525] which specifies the addition of
**workspaces** to Cargo.

[RFC 1525]: https://github.com/rust-lang/rfcs/blob/master/text/1525-cargo-workspace.md

A workspace is a group of crates which are all compiled into the same output
directory and share the same `Cargo.lock` file. This means that dependencies are
cached between builds as well as dependencies all being shared at the same
versions. An update to any one dependency transitively affects all other members
of the workspace.

Typical repository layouts with a crate at the root and a number of path
dependencies simply need to add the following to the root `Cargo.toml`:

```toml
[workspace]
```

Otherwise more advanced configuration may be necessary through the
`package.workspace` or `workspace.members` keys. More information can be found
as part of [RFC 1525].

Author: alexcrichton

src/bin/bench.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, CliError, Human, Config, human};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -91,7 +92,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         },
     };
 
-    let err = try!(ops::run_benches(&root, &ops, &options.arg_args));
+    let ws = try!(Workspace::new(&root, config));
+    let err = try!(ops::run_benches(&ws, &ops, &options.arg_args));
     match err {
         None => Ok(None),
         Some(err) => {

src/bin/build.rs

@@ -1,5 +1,6 @@
 use std::env;
 
+use cargo::core::Workspace;
 use cargo::ops::CompileOptions;
 use cargo::ops;
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -86,6 +87,7 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         target_rustc_args: None,
     };
 
-    try!(ops::compile(&root, &opts));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::compile(&ws, &opts));
     Ok(None)
 }

src/bin/clean.rs

@@ -1,5 +1,6 @@
 use std::env;
 
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -50,6 +51,7 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         target: options.flag_target.as_ref().map(|s| &s[..]),
         release: options.flag_release,
     };
-    try!(ops::clean(&root, &opts));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::clean(&ws, &opts));
     Ok(None)
 }

src/bin/doc.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -84,6 +85,7 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         },
     };
 
-    try!(ops::doc(&root, &doc_opts));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::doc(&ws, &doc_opts));
     Ok(None)
 }

src/bin/fetch.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::find_root_manifest_for_wd;
@@ -38,7 +39,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
                                 options.flag_quiet,
                                 &options.flag_color));
     let root = try!(find_root_manifest_for_wd(options.flag_manifest_path, config.cwd()));
-    try!(ops::fetch(&root, config));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::fetch(&ws));
     Ok(None)
 }
 

src/bin/generate_lockfile.rs

@@ -1,5 +1,6 @@
 use std::env;
 
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::find_root_manifest_for_wd;
@@ -33,6 +34,7 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
                                 &options.flag_color));
     let root = try!(find_root_manifest_for_wd(options.flag_manifest_path, config.cwd()));
 
-    try!(ops::generate_lockfile(&root, config));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::generate_lockfile(&ws));
     Ok(None)
 }

src/bin/metadata.rs

@@ -1,8 +1,4 @@
-extern crate cargo;
-extern crate docopt;
-extern crate rustc_serialize;
-extern crate toml;
-
+use cargo::core::Workspace;
 use cargo::ops::{output_metadata, OutputMetadataOptions, ExportInfo};
 use cargo::util::important_paths::find_root_manifest_for_wd;
 use cargo::util::{CliResult, Config};
@@ -48,12 +44,12 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<ExportInfo
 
     let options = OutputMetadataOptions {
         features: options.flag_features,
-        manifest_path: &manifest,
         no_default_features: options.flag_no_default_features,
         no_deps: options.flag_no_deps,
         version: options.flag_format_version,
     };
 
-    let result = try!(output_metadata(options, config));
+    let ws = try!(Workspace::new(&manifest, config));
+    let result = try!(output_metadata(&ws, &options));
     Ok(Some(result))
 }

src/bin/package.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::find_root_manifest_for_wd;
@@ -38,7 +39,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
                                 options.flag_quiet,
                                 &options.flag_color));
     let root = try!(find_root_manifest_for_wd(options.flag_manifest_path, config.cwd()));
-    try!(ops::package(&root, &ops::PackageOpts {
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::package(&ws, &ops::PackageOpts {
         config: config,
         verify: !options.flag_no_verify,
         list: options.flag_list,

src/bin/pkgid.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -51,9 +52,10 @@ pub fn execute(options: Options,
                                 options.flag_quiet,
                                 &options.flag_color));
     let root = try!(find_root_manifest_for_wd(options.flag_manifest_path.clone(), config.cwd()));
+    let ws = try!(Workspace::new(&root, config));
 
     let spec = options.arg_spec.as_ref().map(|s| &s[..]);
-    let spec = try!(ops::pkgid(&root, spec, config));
+    let spec = try!(ops::pkgid(&ws, spec));
     println!("{}", spec);
     Ok(None)
 }

src/bin/publish.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::find_root_manifest_for_wd;
@@ -47,7 +48,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
     } = options;
 
     let root = try!(find_root_manifest_for_wd(flag_manifest_path.clone(), config.cwd()));
-    try!(ops::publish(&root, &ops::PublishOpts {
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::publish(&ws, &ops::PublishOpts {
         config: config,
         token: token,
         index: host,

src/bin/run.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, CliError, Config, Human};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -85,7 +86,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         target_rustc_args: None,
     };
 
-    match try!(ops::run(&root, &compile_opts, &options.arg_args)) {
+    let ws = try!(Workspace::new(&root, config));
+    match try!(ops::run(&ws, &compile_opts, &options.arg_args)) {
         None => Ok(None),
         Some(err) => {
             // If we never actually spawned the process then that sounds pretty

src/bin/rustc.rs

@@ -1,5 +1,6 @@
 use std::env;
 
+use cargo::core::Workspace;
 use cargo::ops::{CompileOptions, CompileMode};
 use cargo::ops;
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -104,7 +105,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         target_rustc_args: options.arg_opts.as_ref().map(|a| &a[..]),
     };
 
-    try!(ops::compile(&root, &opts));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::compile(&ws, &opts));
     Ok(None)
 }
 

src/bin/rustdoc.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -91,7 +92,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         },
     };
 
-    try!(ops::doc(&root, &doc_opts));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::doc(&ws, &doc_opts));
 
     Ok(None)
 }

src/bin/test.rs

@@ -1,3 +1,4 @@
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, CliError, Human, human, Config};
 use cargo::util::important_paths::{find_root_manifest_for_wd};
@@ -119,7 +120,8 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         },
     };
 
-    let err = try!(ops::run_tests(&root, &ops, &options.arg_args));
+    let ws = try!(Workspace::new(&root, config));
+    let err = try!(ops::run_tests(&ws, &ops, &options.arg_args));
     match err {
         None => Ok(None),
         Some(err) => {

src/bin/update.rs

@@ -1,5 +1,6 @@
 use std::env;
 
+use cargo::core::Workspace;
 use cargo::ops;
 use cargo::util::{CliResult, Config};
 use cargo::util::important_paths::find_root_manifest_for_wd;
@@ -66,6 +67,7 @@ pub fn execute(options: Options, config: &Config) -> CliResult<Option<()>> {
         config: config,
     };
 
-    try!(ops::update_lockfile(&root, &update_opts));
+    let ws = try!(Workspace::new(&root, config));
+    try!(ops::update_lockfile(&ws, &update_opts));
     Ok(None)
 }

src/cargo/core/manifest.rs

@@ -4,9 +4,14 @@ use std::path::{PathBuf, Path};
 use semver::Version;
 use rustc_serialize::{Encoder, Encodable};
 
-use core::{Dependency, PackageId, PackageIdSpec, Summary};
+use core::{Dependency, PackageId, PackageIdSpec, Summary, WorkspaceConfig};
 use core::package_id::Metadata;
 
+pub enum EitherManifest {
+    Real(Manifest),
+    Virtual(VirtualManifest),
+}
+
 /// Contains all the information about a package, as loaded from a Cargo.toml.
 #[derive(Clone, Debug)]
 pub struct Manifest {
@@ -20,6 +25,13 @@ pub struct Manifest {
     profiles: Profiles,
     publish: bool,
     replace: Vec<(PackageIdSpec, Dependency)>,
+    workspace: WorkspaceConfig,
+}
+
+#[derive(Clone, Debug)]
+pub struct VirtualManifest {
+    replace: Vec<(PackageIdSpec, Dependency)>,
+    workspace: WorkspaceConfig,
 }
 
 /// General metadata about a package which is just blindly uploaded to the
@@ -175,7 +187,8 @@ impl Manifest {
                metadata: ManifestMetadata,
                profiles: Profiles,
                publish: bool,
-               replace: Vec<(PackageIdSpec, Dependency)>) -> Manifest {
+               replace: Vec<(PackageIdSpec, Dependency)>,
+               workspace: WorkspaceConfig) -> Manifest {
         Manifest {
             summary: summary,
             targets: targets,
@@ -187,6 +200,7 @@ impl Manifest {
             profiles: profiles,
             publish: publish,
             replace: replace,
+            workspace: workspace,
         }
     }
 
@@ -207,6 +221,10 @@ impl Manifest {
         self.links.as_ref().map(|s| &s[..])
     }
 
+    pub fn workspace_config(&self) -> &WorkspaceConfig {
+        &self.workspace
+    }
+
     pub fn add_warning(&mut self, s: String) {
         self.warnings.push(s)
     }
@@ -216,6 +234,24 @@ impl Manifest {
     }
 }
 
+impl VirtualManifest {
+    pub fn new(replace: Vec<(PackageIdSpec, Dependency)>,
+               workspace: WorkspaceConfig) -> VirtualManifest {
+        VirtualManifest {
+            replace: replace,
+            workspace: workspace,
+        }
+    }
+
+    pub fn replace(&self) -> &[(PackageIdSpec, Dependency)] {
+        &self.replace
+    }
+
+    pub fn workspace_config(&self) -> &WorkspaceConfig {
+        &self.workspace
+    }
+}
+
 impl Target {
     fn blank() -> Target {
         Target {

src/cargo/core/mod.rs

@@ -1,5 +1,6 @@
 pub use self::dependency::{Dependency, DependencyInner};
 pub use self::manifest::{Manifest, Target, TargetKind, Profile, LibKind, Profiles};
+pub use self::manifest::{EitherManifest, VirtualManifest};
 pub use self::package::{Package, PackageSet};
 pub use self::package_id::{PackageId, Metadata};
 pub use self::package_id_spec::PackageIdSpec;
@@ -8,6 +9,7 @@ pub use self::resolver::Resolve;
 pub use self::shell::{Shell, MultiShell, ShellConfig, Verbosity, ColorConfig};
 pub use self::source::{Source, SourceId, SourceMap, GitReference};
 pub use self::summary::Summary;
+pub use self::workspace::{Workspace, WorkspaceConfig};
 
 pub mod source;
 pub mod package;
@@ -19,3 +21,4 @@ pub mod summary;
 pub mod shell;
 pub mod registry;
 mod package_id_spec;
+mod workspace;