fix: Make sure that environments are not completely overridden

crates/pixi_manifest/src/feature.rs

@@ -270,12 +270,19 @@ impl Feature {
     ///
     /// Returns `None` if this feature does not define any target with an
     /// activation.
-    pub fn activation_env(&self, platform: Option<Platform>) -> Option<&IndexMap<String, String>> {
+    pub fn activation_env(&self, platform: Option<Platform>) -> IndexMap<String, String> {
         self.targets
             .resolve(platform)
             .filter_map(|t| t.activation.as_ref())
             .filter_map(|a| a.env.as_ref())
-            .next()
+            .fold(IndexMap::new(), |mut acc, x| {
+                for (k, v) in x {
+                    if !acc.contains_key(k) {
+                        acc.insert(k.clone(), v.clone());
+                    }
+                }
+                acc
+            })
     }
 
     /// Returns true if the feature contains any reference to a pypi

src/project/environment.rs

@@ -261,7 +261,7 @@ impl<'p> Environment<'p> {
     /// are defined for the environment.
     pub(crate) fn activation_env(&self, platform: Option<Platform>) -> IndexMap<String, String> {
         self.features()
-            .filter_map(|f| f.activation_env(platform))
+            .map(|f| f.activation_env(platform))
             .fold(IndexMap::new(), |mut acc, env| {
                 acc.extend(env.iter().map(|(k, v)| (k.clone(), v.clone())));
                 acc
@@ -329,6 +329,7 @@ impl<'p> Hash for Environment<'p> {
 mod tests {
     use std::{collections::HashSet, path::Path};
 
+    use indexmap::indexmap;
     use insta::assert_snapshot;
     use itertools::Itertools;
     use pixi_manifest::CondaDependencies;
@@ -493,23 +494,23 @@ mod tests {
         let manifest = Project::from_str(
             Path::new("pixi.toml"),
             r#"
-        [project]
-        name = "foobar"
-        channels = []
-        platforms = ["linux-64", "osx-64"]
+            [project]
+            name = "foobar"
+            channels = []
+            platforms = ["linux-64", "osx-64"]
 
-        [activation]
-        scripts = ["default.bat"]
+            [activation]
+            scripts = ["default.bat"]
 
-        [target.linux-64.activation]
-        scripts = ["linux.bat"]
+            [target.linux-64.activation]
+            scripts = ["linux.bat"]
 
-        [feature.foo.activation]
-        scripts = ["foo.bat"]
+            [feature.foo.activation]
+            scripts = ["foo.bat"]
 
-        [environments]
-        foo = ["foo"]
-                "#,
+            [environments]
+            foo = ["foo"]
+            "#,
         )
         .unwrap();
 
@@ -524,6 +525,49 @@ mod tests {
         );
     }
 
+    #[test]
+    fn test_activation_env() {
+        let manifest = Project::from_str(
+            Path::new("pixi.toml"),
+            r#"
+            [project]
+            name = "foobar"
+            channels = []
+            platforms = ["linux-64", "osx-64"]
+
+            [activation.env]
+            DEFAULT_VAR = "1"
+
+            [target.linux-64.activation.env]
+            LINUX_VAR = "1"
+
+            [feature.foo.activation.env]
+            FOO_VAR = "1"
+
+            [environments]
+            foo = ["foo"]
+            "#,
+        )
+        .unwrap();
+
+        let default_env = manifest.default_environment();
+        let foo_env = manifest.environment("foo").unwrap();
+        assert_eq!(
+            foo_env.activation_env(None),
+            indexmap! {
+                "FOO_VAR".to_string() => "1".to_string(),
+                "DEFAULT_VAR".to_string() => "1".to_string(),
+            }
+        );
+        assert_eq!(
+            default_env.activation_env(Some(Platform::Linux64)),
+            indexmap! {
+                "LINUX_VAR".to_string() => "1".to_string(),
+                "DEFAULT_VAR".to_string() => "1".to_string(),
+            }
+        );
+    }
+
     #[test]
     fn test_channel_feature_priority() {
         let manifest = Project::from_str(

src/project/snapshots/pixi__project__tests__activation_scripts.snap

@@ -1,6 +1,7 @@
 ---
 source: src/project/mod.rs
-expression: "format!(\"= Linux64\\n{}\\n\\n= Win64\\n{}\\n\\n= OsxArm64\\n{}\",\n    fmt_activation_scripts(project.activation_scripts(Platform ::\n    Linux64).unwrap()),\n    fmt_activation_scripts(project.activation_scripts(Platform ::\n    Win64).unwrap()),\n    fmt_activation_scripts(project.activation_scripts(Platform ::\n    OsxArm64).unwrap()))"
+expression: "format!(\"= Linux64\\n{}\\n\\n= Win64\\n{}\\n\\n= OsxArm64\\n{}\",\nfmt_activation_scripts(project.default_environment().activation_scripts(Some(Platform::Linux64))),\nfmt_activation_scripts(project.default_environment().activation_scripts(Some(Platform::Win64))),\nfmt_activation_scripts(project.default_environment().activation_scripts(Some(Platform::OsxArm64))))"
+snapshot_kind: text
 ---
 = Linux64
 Cargo.toml