New semantics for --features flag

src/cargo/core/features.rs

@@ -292,6 +292,7 @@ pub struct CliUnstable {
  pub no_index_update: bool,
  pub avoid_dev_deps: bool,
  pub minimal_versions: bool,
+ pub package_features: bool,
 }
 
 impl CliUnstable {
@@ -325,6 +326,7 @@ impl CliUnstable {
  "no-index-update" => self.no_index_update = true,
  "avoid-dev-deps" => self.avoid_dev_deps = true,
  "minimal-versions" => self.minimal_versions = true,
+ "package-features" => self.package_features = true,
  _ => bail!("unknown `-Z` flag specified: {}", k),
  }
 

src/cargo/ops/resolve.rs

@@ -213,53 +213,86 @@ pub fn resolve_with_previous<'a, 'cfg>(
  registry.lock_patches();
  }
 
- let mut summaries = Vec::new();
+
  for member in ws.members() {
  registry.add_sources(&[member.package_id().source_id().clone()])?;
- let method_to_resolve = match method {
- // When everything for a workspace we want to be sure to resolve all
- // members in the workspace, so propagate the `Method::Everything`.
- Method::Everything => Method::Everything,
-
- // If we're not resolving everything though then we're constructing the
- // exact crate graph we're going to build. Here we don't necessarily
- // want to keep around all workspace crates as they may not all be
- // built/tested.
- //
- // Additionally, the `method` specified represents command line
- // flags, which really only matters for the current package
- // (determined by the cwd). If other packages are specified (via
- // `-p`) then the command line flags like features don't apply to
- // them.
- //
- // As a result, if this `member` is the current member of the
- // workspace, then we use `method` specified. Otherwise we use a
- // base method with no features specified but using default features
- // for any other packages specified with `-p`.
- Method::Required { dev_deps, .. } => {
- let base = Method::Required {
- dev_deps,
- features: &[],
- all_features: false,
- uses_default_features: true,
- };
- let member_id = member.package_id();
- match ws.current_opt() {
- Some(current) if member_id == current.package_id() => method,
- _ => {
- if specs.iter().any(|spec| spec.matches(member_id)) {
- base
- } else {
- continue;
- }
+ }
+
+ let mut summaries = Vec::new();
+ if ws.config().cli_unstable().package_features {
+ let mut members = Vec::new();
+ match method {
+ Method::Everything => members.extend(ws.members()),
+ Method::Required { features, all_features, uses_default_features, .. } => {
+ if specs.len() > 1 && !features.is_empty() {
+ bail!("cannot specify features for more than one package");
+ }
+ members.extend(
+ ws.members().filter(|m| specs.iter().any(|spec| spec.matches(m.package_id())))
+ );
+ // Edge case: running `cargo build -p foo`, where `foo` is not a member
+ // of current workspace. Add all packages from workspace to get `foo`
+ // into the resolution graph.
+ if members.is_empty() {
+ if !(features.is_empty() && !all_features && uses_default_features) {
+ bail!("cannot specify features for packages outside of workspace");
  }
+ members.extend(ws.members());
  }
  }
- };
+ }
+ for member in members {
+ let summary = registry.lock(member.summary().clone());
+ summaries.push((summary, method))
+ }
+ } else {
+ for member in ws.members() {
+ let method_to_resolve = match method {
+ // When everything for a workspace we want to be sure to resolve all
+ // members in the workspace, so propagate the `Method::Everything`.
+ Method::Everything => Method::Everything,
+
+ // If we're not resolving everything though then we're constructing the
+ // exact crate graph we're going to build. Here we don't necessarily
+ // want to keep around all workspace crates as they may not all be
+ // built/tested.
+ //
+ // Additionally, the `method` specified represents command line
+ // flags, which really only matters for the current package
+ // (determined by the cwd). If other packages are specified (via
+ // `-p`) then the command line flags like features don't apply to
+ // them.
+ //
+ // As a result, if this `member` is the current member of the
+ // workspace, then we use `method` specified. Otherwise we use a
+ // base method with no features specified but using default features
+ // for any other packages specified with `-p`.
+ Method::Required { dev_deps, .. } => {
+ let base = Method::Required {
+ dev_deps,
+ features: &[],
+ all_features: false,
+ uses_default_features: true,
+ };
+ let member_id = member.package_id();
+ match ws.current_opt() {
+ Some(current) if member_id == current.package_id() => method,
+ _ => {
+ if specs.iter().any(|spec| spec.matches(member_id)) {
+ base
+ } else {
+ continue;
+ }
+ }
+ }
+ }
+ };
+
+ let summary = registry.lock(member.summary().clone());
+ summaries.push((summary, method_to_resolve));
+ }
+ };
 
- let summary = registry.lock(member.summary().clone());
- summaries.push((summary, method_to_resolve));
- }
 
  let root_replace = ws.root_replace();
 

tests/testsuite/features.rs

@@ -3,7 +3,9 @@ use std::io::prelude::*;
 
 use cargotest::support::paths::CargoPathExt;
 use cargotest::support::{execs, project};
+use cargotest::ChannelChanger;
 use hamcrest::assert_that;
+use cargotest::support::registry::Package;
 
 #[test]
 fn invalid1() {
@@ -1629,3 +1631,83 @@ fn many_cli_features_comma_and_space_delimited() {
  )),
  );
 }
+
+#[test]
+fn combining_features_and_package() {
+ Package::new("dep", "1.0.0").publish();
+
+ let p = project("ws")
+ .file(
+ "Cargo.toml",
+ r#"
+ [project]
+ name = "ws"
+ version = "0.0.1"
+ authors = []
+
+ [workspace]
+ members = ["foo"]
+
+ [dependencies]
+ dep = "1"
+ "#,
+ )
+ .file("src/lib.rs", "")
+ .file(
+ "foo/Cargo.toml",
+ r#"
+ [package]
+ name = "foo"
+ version = "0.0.1"
+ authors = []
+ [features]
+ main = []
+ "#,
+ )
+ .file("foo/src/main.rs", r#"
+ #[cfg(feature = "main")]
+ fn main() {}
+ "#)
+ .build();
+
+ assert_that(
+ p.cargo("build -Z package-features --all --features main")
+ .masquerade_as_nightly_cargo(),
+ execs().with_status(101).with_stderr_contains("\
+[ERROR] cannot specify features for more than one package"
+ ),
+ );
+
+ assert_that(
+ p.cargo("build -Z package-features --package dep --features main")
+ .masquerade_as_nightly_cargo(),
+ execs().with_status(101).with_stderr_contains("\
+[ERROR] cannot specify features for packages outside of workspace"
+ ),
+ );
+ assert_that(
+ p.cargo("build -Z package-features --package dep --all-features")
+ .masquerade_as_nightly_cargo(),
+ execs().with_status(101).with_stderr_contains("\
+[ERROR] cannot specify features for packages outside of workspace"
+ ),
+ );
+ assert_that(
+ p.cargo("build -Z package-features --package dep --no-default-features")
+ .masquerade_as_nightly_cargo(),
+ execs().with_status(101).with_stderr_contains("\
+[ERROR] cannot specify features for packages outside of workspace"
+ ),
+ );
+
+ assert_that(
+ p.cargo("build -Z package-features --all --all-features")
+ .masquerade_as_nightly_cargo(),
+ execs().with_status(0),
+ );
+ assert_that(
+ p.cargo("run -Z package-features --package foo --features main")
+ .masquerade_as_nightly_cargo(),
+ execs().with_status(0),
+ );
+}