docs: prefer inline environments over single-feature environments

crates/pixi/tests/integration_rust/add_tests.rs

@@ -4,7 +4,7 @@ use pep508_rs::MarkerTree;
 use pixi_cli::cli_config::GitRev;
 use pixi_consts::consts;
 use pixi_core::DependencyType;
-use pixi_manifest::{FeaturesExt, SpecType};
+use pixi_manifest::{FeatureName, FeaturesExt, SpecType};
 use pixi_pypi_spec::{PixiPypiSource, PixiPypiSpec, PypiPackageName, VersionOrStar};
 use rattler_conda_types::{PackageName, Platform};
 use tempfile::TempDir;
@@ -633,7 +633,7 @@ async fn add_unconstrained_dependency() {
     let bar_spec = project
         .workspace
         .value
-        .feature("unreferenced")
+        .feature(&FeatureName::from("unreferenced"))
         .expect("feature 'unreferenced' is missing")
         .combined_dependencies(None)
         .unwrap_or_default()

crates/pixi/tests/integration_rust/common/mod.rs

@@ -840,7 +840,7 @@ impl TasksControl<'_> {
                 commands: vec![],
                 depends_on: None,
                 platform: platform.map(Into::into),
-                feature: feature_name.non_default().map(str::to_owned),
+                feature: feature_name.non_default().map(FeatureName::from),
                 cwd: None,
                 default_environment: None,
                 env: Default::default(),
@@ -856,7 +856,7 @@ impl TasksControl<'_> {
         &self,
         name: TaskName,
         platform: Option<Platform>,
-        feature_name: Option<String>,
+        feature_name: Option<FeatureName>,
     ) -> miette::Result<()> {
         task::execute(task::Args {
             config_source: isolated_config_source(),

crates/pixi_api/src/workspace/add/mod.rs

@@ -36,7 +36,7 @@ pub async fn add_conda_dep(
     let pixi_platforms = resolve_platforms(&workspace_platforms, &dep_options.platforms)?;
     workspace
         .manifest()
-        .add_platforms(pixi_platforms.iter(), &FeatureName::DEFAULT)?;
+        .add_platforms(pixi_platforms.iter(), &FeatureName::Default)?;
 
     let mut match_specs = IndexMap::default();
     let mut source_specs = IndexMap::default();
@@ -137,7 +137,7 @@ pub async fn add_pypi_dep(
     let pixi_platforms = resolve_platforms(&workspace_platforms, &options.platforms)?;
     workspace
         .manifest()
-        .add_platforms(pixi_platforms.iter(), &FeatureName::DEFAULT)?;
+        .add_platforms(pixi_platforms.iter(), &FeatureName::Default)?;
 
     // TODO: add dry_run logic to add
     let dry_run = false;

crates/pixi_api/src/workspace/remove/mod.rs

@@ -167,7 +167,7 @@ mod tests {
 
     fn options() -> DependencyOptions {
         DependencyOptions {
-            feature: FeatureName::DEFAULT,
+            feature: FeatureName::Default,
             platforms: vec![],
             no_install: true,
             lock_file_usage: LockFileUsage::Frozen,

crates/pixi_api/src/workspace/task/mod.rs

@@ -53,7 +53,7 @@ fn declare_platform_and_add_task(
     if let Some(p) = &pixi_platform {
         workspace
             .manifest()
-            .add_platforms(std::slice::from_ref(p).iter(), &FeatureName::DEFAULT)?;
+            .add_platforms(std::slice::from_ref(p).iter(), &FeatureName::Default)?;
     }
     workspace
         .manifest()
@@ -151,7 +151,7 @@ pub async fn alias_task<I: Interface>(
         &mut workspace,
         &name,
         &task,
-        &FeatureName::DEFAULT,
+        &FeatureName::Default,
         platform.as_ref(),
     )?;
     workspace.save().await.into_diagnostic()?;

crates/pixi_cli/src/cli_config.rs

@@ -1,3 +1,5 @@
+use std::str::FromStr;
+
 use crate::has_specs::HasSpecs;
 use clap::Parser;
 use indexmap::IndexMap;
@@ -301,7 +303,7 @@ pub struct DependencyConfig {
     pub platforms: Vec<PixiPlatformName>,
 
     /// The feature for which the dependency should be modified.
-    #[clap(long, short, default_value_t)]
+    #[clap(long, short, default_value_t, value_parser = FeatureName::from_str)]
     pub feature: FeatureName,
 
     /// The git url to use when adding a git dependency

crates/pixi_cli/src/import.rs

@@ -56,8 +56,8 @@ pub struct Args {
     pub environment: Option<String>,
 
     /// A name for the created feature
-    #[clap(long, short)]
-    pub feature: Option<String>,
+    #[clap(long, short, value_parser = FeatureName::from_str)]
+    pub feature: Option<FeatureName>,
 
     #[clap(flatten)]
     pub config: ConfigCli,
@@ -87,19 +87,19 @@ pub async fn execute(args: Args) -> miette::Result<()> {
 struct MissingEnvironmentName;
 
 fn get_feature_and_environment(
-    feature_arg: &Option<String>,
+    feature_arg: &Option<FeatureName>,
     environment_arg: &Option<String>,
     fallback: impl Fn() -> Result<String, MissingEnvironmentName>,
 ) -> Result<(FeatureName, EnvironmentName), miette::Report> {
     let feature_string = match (feature_arg, environment_arg) {
-        (Some(f), _) => f.clone(),
+        (Some(f), _) => f.as_str().to_string(),
         (_, Some(e)) => e.clone(),
         _ => fallback()?,
     };
 
     let environment_string = match (environment_arg, feature_arg) {
         (Some(e), _) => e.clone(),
-        (_, Some(f)) => f.clone(),
+        (_, Some(f)) => f.as_str().to_string(),
         _ => fallback()?,
     };
 

crates/pixi_cli/src/info.rs

@@ -144,7 +144,7 @@ impl Display for EnvironmentInfo {
             bold.apply_to("Features"),
             self.features
                 .iter()
-                .map(|feature| feature.fancy_display())
+                .map(|feature| consts::FEATURE_STYLE.apply_to(feature.to_string()))
                 .format(", ")
         )?;
         if let Some(solve_group) = &self.solve_group {

crates/pixi_cli/src/remove/error.rs

@@ -322,7 +322,7 @@ pandas = "*"
                 &manifest,
                 "polars",
                 DependencyType::CondaDependency(SpecType::Run),
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @r"
@@ -341,7 +341,7 @@ pandas = "*"
                 &manifest,
                 "ruff",
                 DependencyType::PypiDependency,
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @r"
@@ -360,7 +360,7 @@ pandas = "*"
                 &manifest,
                 "openssl",
                 DependencyType::CondaDependency(SpecType::Run),
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @r"
@@ -379,7 +379,7 @@ pandas = "*"
                 &manifest,
                 "cmake",
                 DependencyType::CondaDependency(SpecType::Run),
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @r"
@@ -399,7 +399,7 @@ pandas = "*"
                 &manifest,
                 "numpy",
                 DependencyType::CondaDependency(SpecType::Run),
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @r"
@@ -419,7 +419,7 @@ pandas = "*"
                 &manifest,
                 "polrs",
                 DependencyType::PypiDependency,
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @r"
@@ -438,7 +438,7 @@ pandas = "*"
                 &manifest,
                 "fizzbuzz",
                 DependencyType::CondaDependency(SpecType::Run),
-                &FeatureName::DEFAULT,
+                &FeatureName::Default,
                 &[],
             ),
             @"  × dependency `fizzbuzz` was not found in dependencies"

crates/pixi_cli/src/task.rs

@@ -57,8 +57,8 @@ pub struct RemoveArgs {
     pub platform: Option<PixiPlatformName>,
 
     /// The feature for which the task should be removed.
-    #[arg(long, short)]
-    pub feature: Option<String>,
+    #[arg(long, short, value_parser = FeatureName::from_str)]
+    pub feature: Option<FeatureName>,
 }
 
 #[derive(Parser, Debug, Clone)]
@@ -81,8 +81,8 @@ pub struct AddArgs {
     pub platform: Option<PixiPlatformName>,
 
     /// The feature for which the task should be added.
-    #[arg(long, short)]
-    pub feature: Option<String>,
+    #[arg(long, short, value_parser = FeatureName::from_str)]
+    pub feature: Option<FeatureName>,
 
     /// The working directory relative to the root of the workspace.
     #[arg(long)]
@@ -417,10 +417,7 @@ async fn add_task(
     workspace_ctx: WorkspaceContext<CliInterface>,
     args: AddArgs,
 ) -> miette::Result<()> {
-    let feature = args
-        .clone()
-        .feature
-        .map_or_else(FeatureName::default, FeatureName::from);
+    let feature = args.feature.clone().unwrap_or_default();
 
     workspace_ctx
         .add_task(
@@ -450,12 +447,7 @@ async fn remove_tasks(
     args: RemoveArgs,
 ) -> miette::Result<()> {
     workspace_ctx
-        .remove_task(
-            args.names,
-            args.platform,
-            args.feature
-                .map_or_else(FeatureName::default, FeatureName::from),
-        )
+        .remove_task(args.names, args.platform, args.feature.unwrap_or_default())
         .await
 }
 

crates/pixi_cli/src/upgrade.rs

@@ -1,3 +1,5 @@
+use std::str::FromStr;
+
 use std::cmp::Ordering;
 
 use clap::Parser;
@@ -62,7 +64,7 @@ pub struct UpgradeSpecsArgs {
     pub packages: Option<Vec<String>>,
 
     /// The feature to update
-    #[clap(long = "feature", short = 'f')]
+    #[clap(long = "feature", short = 'f', value_parser = FeatureName::from_str)]
     pub feature: Option<FeatureName>,
 
     /// The packages which should be excluded

crates/pixi_cli/src/workspace/channel.rs

@@ -1,3 +1,5 @@
+use std::str::FromStr;
+
 use std::io::Write;
 
 use clap::Parser;
@@ -6,6 +8,7 @@ use miette::IntoDiagnostic;
 use pixi_api::{WorkspaceContext, workspace::ChannelOptions};
 use pixi_config::ConfigCli;
 use pixi_core::WorkspaceLocator;
+use pixi_manifest::FeatureName;
 use rattler_conda_types::NamedChannelOrUrl;
 
 use crate::{
@@ -50,8 +53,8 @@ pub struct AddRemoveArgs {
     pub config: ConfigCli,
 
     /// The name of the feature to modify.
-    #[clap(long, short)]
-    pub feature: Option<String>,
+    #[clap(long, short, value_parser = FeatureName::from_str)]
+    pub feature: Option<FeatureName>,
 }
 
 #[derive(Parser, Debug, Default, Clone)]
@@ -67,7 +70,7 @@ impl TryFrom<&AddRemoveArgs> for ChannelOptions {
     fn try_from(args: &AddRemoveArgs) -> Result<Self, Self::Error> {
         Ok(Self {
             channels: args.channel.clone(),
-            feature: args.feature.clone(),
+            feature: args.feature.clone().map(|f| f.to_string()),
             no_install: args.no_install_config.no_install,
             lock_file_usage: args.lock_file_update_config.lock_file_usage()?,
         })

crates/pixi_cli/src/workspace/feature.rs

@@ -1,3 +1,5 @@
+use std::str::FromStr;
+
 use std::io::Write;
 
 use clap::Parser;
@@ -27,6 +29,7 @@ pub struct Args {
 #[derive(Parser, Debug)]
 pub struct RemoveArgs {
     /// The name of the feature to remove
+    #[clap(value_parser = FeatureName::from_str)]
     pub feature: FeatureName,
 }
 

crates/pixi_cli/src/workspace/platform.rs

@@ -8,8 +8,8 @@ use pixi_api::WorkspaceContext;
 use pixi_core::WorkspaceLocator;
 use pixi_core::workspace::{PlatformOverrides, PlatformSource};
 use pixi_manifest::{
-    FeaturesExt, HasWorkspaceManifest, PixiPlatform, PixiPlatformName, PlatformEdit, PlatformMove,
-    platform::subdir_default_virtual_packages,
+    FeatureName, FeaturesExt, HasWorkspaceManifest, PixiPlatform, PixiPlatformName, PlatformEdit,
+    PlatformMove, platform::subdir_default_virtual_packages,
 };
 use rattler_conda_types::{GenericVirtualPackage, PackageName, Platform, Version};
 use rattler_virtual_packages::{VirtualPackageOverrides, VirtualPackages};
@@ -316,8 +316,8 @@ pub struct AddArgs {
     pub no_install: bool,
 
     /// The name of the feature to add the platform to.
-    #[clap(long, short)]
-    pub feature: Option<String>,
+    #[clap(long, short, value_parser = FeatureName::from_str)]
+    pub feature: Option<FeatureName>,
 }
 
 #[derive(Parser, Debug)]
@@ -395,8 +395,8 @@ pub struct RemoveArgs {
     pub no_install: bool,
 
     /// The name of the feature to remove the platform from.
-    #[clap(long, short)]
-    pub feature: Option<String>,
+    #[clap(long, short, value_parser = FeatureName::from_str)]
+    pub feature: Option<FeatureName>,
 }
 
 #[derive(Parser, Debug, Default)]
@@ -498,7 +498,11 @@ async fn execute_add(
     }
 
     workspace_ctx
-        .add_platforms(platforms, args.no_install, args.feature)
+        .add_platforms(
+            platforms,
+            args.no_install,
+            args.feature.map(|f| f.to_string()),
+        )
         .await
 }
 
@@ -654,7 +658,11 @@ async fn execute_remove(
         })
         .collect::<miette::Result<Vec<_>>>()?;
     workspace_ctx
-        .remove_platforms(platforms, args.no_install, args.feature)
+        .remove_platforms(
+            platforms,
+            args.no_install,
+            args.feature.map(|f| f.to_string()),
+        )
         .await
 }
 

crates/pixi_consts/src/consts.rs

@@ -9,6 +9,11 @@ use url::Url;
 
 pub const DEFAULT_ENVIRONMENT_NAME: &str = "default";
 pub const DEFAULT_FEATURE_NAME: &str = DEFAULT_ENVIRONMENT_NAME;
+
+/// Prefix of the implicit feature that is synthesized for an environment which
+/// defines dependencies inline. This prefix is reserved: user-defined features
+/// may not start with it.
+pub const ENVIRONMENT_FEATURE_PREFIX: &str = "env:";
 pub const PYPROJECT_PIXI_PREFIX: &str = "tool.pixi";
 
 pub const WORKSPACE_MANIFEST: &str = "pixi.toml";

crates/pixi_core/src/workspace/environment.rs

@@ -475,7 +475,7 @@ impl<'p> HasFeaturesIter<'p> for Environment<'p> {
         let environment_features = self.environment.features.iter().map(|feature_name| {
             manifest
                 .features
-                .get(&FeatureName::from(feature_name.clone()))
+                .get(feature_name)
                 .expect("feature usage should have been validated upfront")
         });