Make alumni field non-optional

src/schema.rs

@@ -230,6 +230,11 @@ impl Team {
         self.discord_roles.as_ref()
     }
 
+    /// Exposed only for validation.
+    pub(crate) fn raw_people(&self) -> &TeamPeople {
+        &self.people
+    }
+
     pub(crate) fn members<'a>(&'a self, data: &'a Data) -> Result<HashSet<&'a str>, Error> {
         let mut members: HashSet<_> = self.people.members.iter().map(|s| s.as_str()).collect();
 
@@ -288,7 +293,7 @@ impl Team {
     }
 
     pub(crate) fn alumni(&self) -> &[String] {
-        &self.people.alumni
+        self.people.alumni.as_ref().map_or(&[], Vec::as_slice)
     }
 
     pub(crate) fn raw_lists(&self) -> &[TeamList] {
@@ -498,23 +503,22 @@ impl std::cmp::Ord for GitHubTeam<'_> {
 
 #[derive(serde_derive::Deserialize, Debug)]
 #[serde(rename_all = "kebab-case", deny_unknown_fields)]
-struct TeamPeople {
-    leads: Vec<String>,
-    members: Vec<String>,
-    #[serde(default)]
-    alumni: Vec<String>,
+pub(crate) struct TeamPeople {
+    pub leads: Vec<String>,
+    pub members: Vec<String>,
+    pub alumni: Option<Vec<String>>,
     #[serde(default)]
-    included_teams: Vec<String>,
+    pub included_teams: Vec<String>,
     #[serde(default = "default_false")]
-    include_team_leads: bool,
+    pub include_team_leads: bool,
     #[serde(default = "default_false")]
-    include_wg_leads: bool,
+    pub include_wg_leads: bool,
     #[serde(default = "default_false")]
-    include_project_group_leads: bool,
+    pub include_project_group_leads: bool,
     #[serde(default = "default_false")]
-    include_all_team_members: bool,
+    pub include_all_team_members: bool,
     #[serde(default = "default_false")]
-    include_all_alumni: bool,
+    pub include_all_alumni: bool,
 }
 
 #[derive(serde::Deserialize, Debug)]

src/validate.rs

@@ -1,6 +1,6 @@
 use crate::data::Data;
 use crate::github::GitHubApi;
-use crate::schema::{Email, Permissions, Team, TeamKind, ZulipGroupMember};
+use crate::schema::{Email, Permissions, Team, TeamKind, TeamPeople, ZulipGroupMember};
 use crate::zulip::ZulipApi;
 use anyhow::{bail, Error};
 use log::{error, warn};
@@ -241,6 +241,50 @@ fn validate_alumni(data: &Data, errors: &mut Vec<String>) {
     if !alumni_team.explicit_members().is_empty() {
         errors.push("'alumni' team must not have explicit members; move them to the appropriate team's alumni entry".to_owned());
     }
+
+    // Teams must contain an `alumni = […]` field (even if empty) so that there
+    // is an obvious place to move contributors within the same file when
+    // removing from `members`.
+    //
+    // Marker teams are exempt from this, as well as teams which comprise only
+    // members of other teams via `include-team-leads` or similar; they do not
+    // need `alumni = […]`. For these teams, the correct place to put alumni is
+    // in the same team they're being included from.
+    wrapper(data.teams(), errors, |team, _| {
+        // Exhaustive destructuring to ensure this code is touched if a new
+        // "include" settings is introduced.
+        let TeamPeople {
+            leads: _,
+            members,
+            alumni,
+            included_teams,
+            include_team_leads,
+            include_wg_leads,
+            include_project_group_leads,
+            include_all_team_members,
+            include_all_alumni,
+        } = team.raw_people();
+
+        if alumni.is_none() {
+            let exempt_team_kind = match team.kind() {
+                TeamKind::MarkerTeam => true,
+                TeamKind::Team | TeamKind::WorkingGroup | TeamKind::ProjectGroup => false,
+            };
+            let exempt_composition = members.is_empty() // intentionally not team.members(data).is_empty()
+                && (*include_team_leads
+                    || *include_wg_leads
+                    || *include_project_group_leads
+                    || *include_all_team_members
+                    || *include_all_alumni
+                    || !included_teams.is_empty());
+            let exempt = exempt_team_kind || exempt_composition;
+            if !exempt {
+                let team_name = team.name();
+                bail!("team '{team_name}' needs an `alumni = []` entry");
+            }
+        }
+        Ok(())
+    });
 }
 
 fn validate_archived_teams(data: &Data, errors: &mut Vec<String>) {

teams/community-ctcft.toml

@@ -12,6 +12,7 @@ members = [
     "technetos",
     "yaahc",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/crate-maintainers.toml

@@ -14,6 +14,7 @@ members = [
   "ChrisDenton",
   "Byron",
 ]
+alumni = []
 
 [permissions]
 bors.libc.review = true

teams/docs-rs-reviewers.toml

@@ -8,6 +8,7 @@ members = [
     "Nemo157",
     "syphar",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/infra-bors.toml

@@ -8,6 +8,7 @@ members = [
     "pietroalbini",
     "Kobzol",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/lang-advisors.toml

@@ -13,6 +13,7 @@ members = [
     "Mark-Simulacrum",
     "wesleywiser",
 ]
+alumni = []
 
 # Granting these permissions because an advisor can use these to help when
 # reviewing a proposed change.

teams/libs-contributors.toml

@@ -16,6 +16,7 @@ members = [
   "sunfishcode",
   "yaahc",
 ]
+alumni = []
 
 [permissions]
 bors.rust.review = true

teams/project-async-crashdump-debugging.toml

@@ -9,6 +9,7 @@ leads = [
 members = [
     "michaelwoerister",
 ]
+alumni = []
 
 [website]
 name = "Async Crashdump Debugging Initiative"

teams/project-dyn-upcasting.toml

@@ -10,6 +10,7 @@ members = [
     "crlf0710",
     "nikomatsakis",
 ]
+alumni = []
 
 [website]
 name = "Dyn Upcasting Initiative"

teams/project-edition-2021.toml

@@ -12,6 +12,7 @@ members = [
     "m-ou-se",
     "rylev"
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/project-edition-2024.toml

@@ -12,6 +12,7 @@ members = [
     "ehuss",
     "m-ou-se",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/project-error-handling.toml

@@ -13,6 +13,7 @@ members = [
     "mystor",
     "senyosimpson",
 ]
+alumni = []
 
 [website]
 name = "Error Handling Project Group"

teams/project-exploit-mitigations.toml

@@ -10,6 +10,7 @@ members = [
     "cuviper",
     "rcvalle",
 ]
+alumni = []
 
 [website]
 name = "Exploit Mitigations Project Group"

teams/project-generic-associated-types.toml

@@ -10,6 +10,7 @@ members = [
     "jackh726",
     "nikomatsakis",
 ]
+alumni = []
 
 [website]
 name = "Generic Associated Types Initiative"

teams/project-impl-trait.toml

@@ -10,6 +10,7 @@ members = [
     "nikomatsakis",
     "oli-obk",
 ]
+alumni = []
 
 [website]
 name = "Impl Trait Initiative"

teams/project-keyword-generics.toml

@@ -13,6 +13,7 @@ members = [
     "yoshuawuyts",
     "lcnr",
 ]
+alumni = []
 
 [website]
 name = "Keyword Generics Initiative"

teams/project-negative-impls.toml

@@ -12,6 +12,7 @@ members = [
     "pnkfelix",
     "spastorino",
 ]
+alumni = []
 
 [website]
 name = "Negative Impls Initiative"

teams/project-stable-mir.toml

@@ -14,6 +14,7 @@ members = [
     "ouz-a",
     "spastorino"
 ]
+alumni = []
 
 [website]
 name = "Stable MIR Project Group"

teams/project-thir-unsafeck.toml

@@ -5,6 +5,7 @@ subteam-of = "compiler"
 [people]
 leads = ["nikomatsakis"]
 members = ["nikomatsakis"]
+alumni = []
 
 [website]
 name = "THIR Unsafety Checker Project Group"

teams/project-trait-system-refactor.toml

@@ -15,6 +15,7 @@ members = [
     "spastorino",
     "lcnr",
 ]
+alumni = []
 
 [website]
 name = "Rustc Trait System Refactor Initiative"

teams/regex.toml

@@ -4,6 +4,7 @@ subteam-of = "libs"
 [people]
 leads = ["BurntSushi"]
 members = ["BurntSushi"]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/rustdoc-contributors.toml

@@ -6,6 +6,7 @@ leads = []
 members = [
     "fmease"
 ]
+alumni = []
 
 [permissions]
 bors.rust.review = true

teams/social-media.toml

@@ -4,6 +4,7 @@ subteam-of = "leadership-council"
 [people]
 leads = ["m-ou-se"]
 members = ["m-ou-se"]
+alumni = []
 
 [[lists]]
 address = "[email protected]"

teams/testing-devex.toml

@@ -10,6 +10,7 @@ members = [
     "thomcc",
     "weihanglo",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/triagebot.toml

@@ -8,6 +8,7 @@ members = [
     "ehuss",
     "spastorino",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/twir-reviewers.toml

@@ -13,6 +13,7 @@ members = [
     "mariannegoldin",
     "U007D"
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/web-presence.toml

@@ -3,6 +3,7 @@ name = "web-presence"
 [people]
 leads = []
 members = []
+alumni = []
 
 [[lists]]
 address = "[email protected]"

teams/wg-allocators.toml

@@ -14,6 +14,7 @@ members = [
     "TimDiekmann",
     "Wodann"
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/wg-bindgen.toml

@@ -8,6 +8,7 @@ members = [
     "emilio",
     "fitzgen",
 ]
+alumni = []
 
 [website]
 name = "Bindgen working group"

teams/wg-compiler-performance.toml

@@ -15,6 +15,7 @@ members = [
     "lqd",
     "nnethercote",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/wg-diagnostics.toml

@@ -12,6 +12,7 @@ members = [
   "estebank",
   "oli-obk",
 ]
+alumni = []
 
 [[github]]
 orgs = ["rust-lang"]

teams/wg-embedded-core.toml

@@ -8,6 +8,7 @@ members = [
     "adamgreig",
     "therealprof",
 ]
+alumni = []
 
 [website]
 name = "Embedded core team"

teams/wg-embedded-cortex-a.toml

@@ -8,6 +8,7 @@ members = [
     "raw-bin",
     "andre-richter",
 ]
+alumni = []
 
 [website]
 name = "Embedded Cortex-A team"

teams/wg-embedded-cortex-m.toml

@@ -11,6 +11,7 @@ members = [
     "thalesfragoso",
     "newAM",
 ]
+alumni = []
 
 [website]
 name = "Embedded Cortex-M team"

teams/wg-embedded-cortex-r.toml

@@ -4,8 +4,8 @@ kind = "working-group"
 
 [people]
 leads = []
-members = [
-]
+members = []
+alumni = []
 
 [website]
 name = "Embedded Cortex-R team"

teams/wg-embedded-hal.toml

@@ -11,6 +11,7 @@ members = [
     "therealprof",
     "MabezDev"
 ]
+alumni = []
 
 [website]
 name = "Embedded HAL team"