8 files changed, 118 insertions, 21 deletions

diff --git a/crates/ra_batch/src/lib.rs b/crates/ra_batch/src/lib.rs
index 2c9645c00..7744ba85a 100644
--- a/crates/ra_batch/src/lib.rs
+++ b/crates/ra_batch/src/lib.rs
@@ -22,7 +22,7 @@ fn vfs_root_to_id(r: ra_vfs::VfsRoot) -> SourceRootId {
 
 pub fn load_cargo(root: &Path) -> Result<(AnalysisHost, FxHashMap<SourceRootId, PackageRoot>)> {
     let root = std::env::current_dir()?.join(root);
-    let ws = ProjectWorkspace::discover(root.as_ref())?;
+    let ws = ProjectWorkspace::discover(root.as_ref(), &Default::default())?;
     let project_roots = ws.to_roots();
     let (sender, receiver) = unbounded();
     let sender = Box::new(move |t| sender.send(t).unwrap());
diff --git a/crates/ra_lsp_server/src/config.rs b/crates/ra_lsp_server/src/config.rs
index 8045f3d60..67942aa41 100644
--- a/crates/ra_lsp_server/src/config.rs
+++ b/crates/ra_lsp_server/src/config.rs
@@ -9,6 +9,7 @@
 
 use rustc_hash::FxHashMap;
 
+use ra_project_model::CargoFeatures;
 use serde::{Deserialize, Deserializer};
 
 /// Client provided initialization options
@@ -37,6 +38,9 @@ pub struct ServerConfig {
 
     /// Fine grained feature flags to disable specific features.
     pub feature_flags: FxHashMap<String, bool>,
+
+    /// Cargo feature configurations.
+    pub cargo_features: CargoFeatures,
 }
 
 impl Default for ServerConfig {
@@ -49,6 +53,7 @@ impl Default for ServerConfig {
             max_inlay_hint_length: None,
             with_sysroot: true,
             feature_flags: FxHashMap::default(),
+            cargo_features: Default::default(),
         }
     }
 }
diff --git a/crates/ra_lsp_server/src/main_loop.rs b/crates/ra_lsp_server/src/main_loop.rs
index 158cac0be..965e7c53c 100644
--- a/crates/ra_lsp_server/src/main_loop.rs
+++ b/crates/ra_lsp_server/src/main_loop.rs
@@ -67,6 +67,7 @@ pub fn main_loop(
                 let workspace = ra_project_model::ProjectWorkspace::discover_with_sysroot(
                     ws_root.as_path(),
                     config.with_sysroot,
+                    &config.cargo_features,
                 );
                 match workspace {
                     Ok(workspace) => loaded_workspaces.push(workspace),
diff --git a/crates/ra_project_model/src/cargo_workspace.rs b/crates/ra_project_model/src/cargo_workspace.rs
index 351997dcd..4a0437da3 100644
--- a/crates/ra_project_model/src/cargo_workspace.rs
+++ b/crates/ra_project_model/src/cargo_workspace.rs
@@ -6,6 +6,7 @@ use cargo_metadata::{CargoOpt, MetadataCommand};
 use ra_arena::{impl_arena_id, Arena, RawId};
 use ra_db::Edition;
 use rustc_hash::FxHashMap;
+use serde::Deserialize;
 
 use crate::Result;
 
@@ -23,6 +24,20 @@ pub struct CargoWorkspace {
     pub(crate) workspace_root: PathBuf,
 }
 
+#[derive(Deserialize, Clone, Debug, PartialEq, Eq, Default)]
+#[serde(rename_all = "camelCase", default)]
+pub struct CargoFeatures {
+    /// Do not activate the `default` feature.
+    pub no_default_features: bool,
+
+    /// Activate all available features
+    pub all_features: bool,
+
+    /// List of features to activate.
+    /// This will be ignored if `cargo_all_features` is true.
+    pub features: Vec<String>,
+}
+
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub struct Package(RawId);
 impl_arena_id!(Package);
@@ -132,9 +147,21 @@ impl Target {
 }
 
 impl CargoWorkspace {
-    pub fn from_cargo_metadata(cargo_toml: &Path) -> Result<CargoWorkspace> {
+    pub fn from_cargo_metadata(
+        cargo_toml: &Path,
+        cargo_features: &CargoFeatures,
+    ) -> Result<CargoWorkspace> {
         let mut meta = MetadataCommand::new();
-        meta.manifest_path(cargo_toml).features(CargoOpt::AllFeatures);
+        meta.manifest_path(cargo_toml);
+        if cargo_features.all_features {
+            meta.features(CargoOpt::AllFeatures);
+        } else if cargo_features.no_default_features {
+            // FIXME: `NoDefaultFeatures` is mutual exclusive with `SomeFeatures`
+            // https://github.com/oli-obk/cargo_metadata/issues/79
+            meta.features(CargoOpt::NoDefaultFeatures);
+        } else {
+            meta.features(CargoOpt::SomeFeatures(cargo_features.features.clone()));
+        }
         if let Some(parent) = cargo_toml.parent() {
             meta.current_dir(parent);
         }
diff --git a/crates/ra_project_model/src/lib.rs b/crates/ra_project_model/src/lib.rs
index 55ff4d6ef..d71b7031a 100644
--- a/crates/ra_project_model/src/lib.rs
+++ b/crates/ra_project_model/src/lib.rs
@@ -18,7 +18,7 @@ use rustc_hash::FxHashMap;
 use serde_json::from_reader;
 
 pub use crate::{
-    cargo_workspace::{CargoWorkspace, Package, Target, TargetKind},
+    cargo_workspace::{CargoFeatures, CargoWorkspace, Package, Target, TargetKind},
     json_project::JsonProject,
     sysroot::Sysroot,
 };
@@ -60,11 +60,15 @@ impl PackageRoot {
 }
 
 impl ProjectWorkspace {
-    pub fn discover(path: &Path) -> Result<ProjectWorkspace> {
-        ProjectWorkspace::discover_with_sysroot(path, true)
+    pub fn discover(path: &Path, cargo_features: &CargoFeatures) -> Result<ProjectWorkspace> {
+        ProjectWorkspace::discover_with_sysroot(path, true, cargo_features)
     }
 
-    pub fn discover_with_sysroot(path: &Path, with_sysroot: bool) -> Result<ProjectWorkspace> {
+    pub fn discover_with_sysroot(
+        path: &Path,
+        with_sysroot: bool,
+        cargo_features: &CargoFeatures,
+    ) -> Result<ProjectWorkspace> {
         match find_rust_project_json(path) {
             Some(json_path) => {
                 let file = File::open(json_path)?;
@@ -73,7 +77,7 @@ impl ProjectWorkspace {
             }
             None => {
                 let cargo_toml = find_cargo_toml(path)?;
-                let cargo = CargoWorkspace::from_cargo_metadata(&cargo_toml)?;
+                let cargo = CargoWorkspace::from_cargo_metadata(&cargo_toml, cargo_features)?;
                 let sysroot =
                     if with_sysroot { Sysroot::discover(&cargo_toml)? } else { Sysroot::default() };
                 Ok(ProjectWorkspace::Cargo { cargo, sysroot })
diff --git a/editors/code/package.json b/editors/code/package.json
index 7bc08ec31..8ed95fda7 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -278,6 +278,21 @@
                     "type": "number",
                     "default": 20,
                     "description": "Maximum length for inlay hints"
+                },
+                "rust-analyzer.cargoFeatures.noDefaultFeatures": {
+                    "type": "boolean",
+                    "default": false,
+                    "description": "Do not activate the `default` feature"
+                },
+                "rust-analyzer.cargoFeatures.allFeatures": {
+                    "type": "boolean",
+                    "default": false,
+                    "description": "Activate all available features"
+                },
+                "rust-analyzer.cargoFeatures.features": {
+                    "type": "array",
+                    "default": [],
+                    "description": "List of features to activate"
                 }
             }
         },
diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index 2d3b6a54e..6d709f7a8 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -15,6 +15,12 @@ export interface CargoWatchOptions {
     ignore: string[];
 }
 
+export interface CargoFeatures {
+    noDefaultFeatures: boolean;
+    allFeatures: boolean;
+    features: string[];
+}
+
 export class Config {
     public highlightingOn = true;
     public rainbowHighlightingOn = false;
@@ -35,8 +41,14 @@ export class Config {
         command: '',
         ignore: [],
     };
+    public cargoFeatures: CargoFeatures = {
+        noDefaultFeatures: false,
+        allFeatures: false,
+        features: [],
+    };
 
     private prevEnhancedTyping: null | boolean = null;
+    private prevCargoFeatures: null | CargoFeatures = null;
 
     constructor() {
         vscode.workspace.onDidChangeConfiguration(_ =>
@@ -47,6 +59,8 @@ export class Config {
 
     public userConfigChanged() {
         const config = vscode.workspace.getConfiguration('rust-analyzer');
+        let requireReloadMessage = null;
+
         if (config.has('highlightingOn')) {
             this.highlightingOn = config.get('highlightingOn') as boolean;
         }
@@ -74,19 +88,7 @@ export class Config {
         }
 
         if (this.prevEnhancedTyping !== this.enableEnhancedTyping) {
-            const reloadAction = 'Reload now';
-            vscode.window
-                .showInformationMessage(
-                    'Changing enhanced typing setting requires a reload',
-                    reloadAction,
-                )
-                .then(selectedAction => {
-                    if (selectedAction === reloadAction) {
-                        vscode.commands.executeCommand(
-                            'workbench.action.reloadWindow',
-                        );
-                    }
-                });
+            requireReloadMessage = 'Changing enhanced typing setting requires a reload';
             this.prevEnhancedTyping = this.enableEnhancedTyping;
         }
 
@@ -153,5 +155,47 @@ export class Config {
         if (config.has('withSysroot')) {
             this.withSysroot = config.get('withSysroot') || false;
         }
+
+        if (config.has('cargoFeatures.noDefaultFeatures')) {
+            this.cargoFeatures.noDefaultFeatures = config.get(
+                'cargoFeatures.noDefaultFeatures',
+                false,
+            );
+        }
+        if (config.has('cargoFeatures.allFeatures')) {
+            this.cargoFeatures.allFeatures = config.get(
+                'cargoFeatures.allFeatures',
+                false,
+            );
+        }
+        if (config.has('cargoFeatures.features')) {
+            this.cargoFeatures.features = config.get(
+                'cargoFeatures.features',
+                [],
+            );
+        }
+
+        if (this.prevCargoFeatures !== null && (
+            this.cargoFeatures.allFeatures !== this.prevCargoFeatures.allFeatures ||
+            this.cargoFeatures.noDefaultFeatures !== this.prevCargoFeatures.noDefaultFeatures ||
+            this.cargoFeatures.features.length !== this.prevCargoFeatures.features.length ||
+            this.cargoFeatures.features.some((v, i) => v !== this.prevCargoFeatures!.features[i])
+        )) {
+            requireReloadMessage = 'Changing cargo features requires a reload';
+        }
+        this.prevCargoFeatures = { ...this.cargoFeatures };
+
+        if (requireReloadMessage !== null) {
+            const reloadAction = 'Reload now';
+            vscode.window
+                .showInformationMessage(requireReloadMessage, reloadAction)
+                .then(selectedAction => {
+                    if (selectedAction === reloadAction) {
+                        vscode.commands.executeCommand(
+                            'workbench.action.reloadWindow',
+                        );
+                    }
+                });
+        }
     }
 }
diff --git a/editors/code/src/server.ts b/editors/code/src/server.ts
index 2fe45f1ed..5ace1d0fa 100644
--- a/editors/code/src/server.ts
+++ b/editors/code/src/server.ts
@@ -59,6 +59,7 @@ export class Server {
                 useClientWatching: Server.config.useClientWatching,
                 featureFlags: Server.config.featureFlags,
                 withSysroot: Server.config.withSysroot,
+                cargoFeatures: Server.config.cargoFeatures,
             },
             traceOutputChannel,
         };