new: Add strict project IDs experiment.

CHANGELOG.md

@@ -4,6 +4,9 @@
 
 #### 🚀 Updates
 
+- Added an `experiments.strictProjectIds` setting to `.moon/workspace.yml`. When enabled, will
+  disallow using original IDs for renamed projects (via the `id` setting) when building the project
+  graph.
 - Updated codegen/template `destination` to be relative from the workspace root if prefixed with
   `/`, otherwise the current working directory.
 

crates/app/src/components.rs

@@ -61,6 +61,7 @@ pub async fn create_project_graph_context(
         extend_project: Emitter::<ExtendProjectEvent>::new(),
         extend_project_graph: Emitter::<ExtendProjectGraphEvent>::new(),
         inherited_tasks: &session.tasks_config,
+        strict_project_ids: session.workspace_config.experiments.strict_project_ids,
         toolchain_config: &session.toolchain_config,
         vcs: Some(session.get_vcs_adapter()?),
         working_dir: &session.working_dir,

crates/config/src/workspace/experiments_config.rs

@@ -17,6 +17,11 @@ cacheable!(
         #[setting(default = true)]
         pub strict_project_aliases: bool,
 
+        /// Disallow referencing the original ID of a renamed project when
+        /// building the project graph.
+        // #[setting(default = true)]
+        pub strict_project_ids: bool,
+
         /// Disallow task relationships with different `runInCI` options.
         #[setting(default = true)]
         pub disallow_run_in_ci_mismatch: bool,

crates/project-graph/src/project_graph_builder.rs

@@ -33,6 +33,7 @@ pub struct ProjectGraphBuilderContext<'app> {
     pub extend_project: Emitter<ExtendProjectEvent>,
     pub extend_project_graph: Emitter<ExtendProjectGraphEvent>,
     pub inherited_tasks: &'app InheritedTasksManager,
+    pub strict_project_ids: bool,
     pub toolchain_config: &'app ToolchainConfig,
     pub vcs: Option<Arc<BoxedVcs>>,
     pub working_dir: &'app Path,
@@ -606,6 +607,7 @@ impl<'app> ProjectGraphBuilder<'app> {
         let context = self.context();
         let mut configs = FxHashMap::default();
         let mut renamed_ids = FxHashMap::default();
+        let mut dupe_original_ids = FxHashSet::default();
 
         for (id, source) in sources {
             debug!(
@@ -621,14 +623,30 @@ impl<'app> ProjectGraphBuilder<'app> {
             // Track ID renames
             if let Some(new_id) = &config.id {
                 if new_id != id {
-                    renamed_ids.insert(id.to_owned(), new_id.to_owned());
+                    if renamed_ids.contains_key(id) {
+                        dupe_original_ids.insert(id.to_owned());
+                    } else {
+                        renamed_ids.insert(id.to_owned(), new_id.to_owned());
+                    }
+
                     *id = new_id.to_owned();
                 }
             }
 
             configs.insert(config.id.clone().unwrap_or(id.to_owned()), config);
         }
 
+        if !dupe_original_ids.is_empty() {
+            trace!(
+                original_ids = ?dupe_original_ids.iter().collect::<Vec<_>>(),
+                "Found multiple projects with the same original ID before being renamed to a custom ID; will ignore these IDs within lookups"
+            );
+
+            for dupe_id in dupe_original_ids {
+                renamed_ids.remove(&dupe_id);
+            }
+        }
+
         debug!("Loaded {} project configs", configs.len());
 
         self.configs.extend(configs);
@@ -657,6 +675,14 @@ impl<'app> ProjectGraphBuilder<'app> {
             }
         };
 
+        if self
+            .context
+            .as_ref()
+            .is_some_and(|ctx| ctx.strict_project_ids)
+        {
+            return id;
+        }
+
         match self.renamed_ids.get(&id) {
             Some(new_id) => new_id.to_owned(),
             None => id,

crates/test-utils/src/project_graph.rs

@@ -98,6 +98,7 @@ impl ProjectGraphContainer {
             extend_project: Emitter::<ExtendProjectEvent>::new(),
             extend_project_graph: Emitter::<ExtendProjectGraphEvent>::new(),
             inherited_tasks: &self.inherited_tasks,
+            strict_project_ids: self.workspace_config.experiments.strict_project_ids,
             toolchain_config: &self.toolchain_config,
             vcs: self.vcs.clone(),
             working_dir: &self.workspace_root,

packages/types/src/workspace-config.ts

@@ -114,6 +114,11 @@ export interface ExperimentsConfig {
 	 * @deprecated
 	 */
 	strictProjectAliases?: boolean;
+	/**
+	 * Disallow referencing the original ID of a renamed project when
+	 * building the project graph.
+	 */
+	strictProjectIds: boolean;
 	/**
 	 * @default true
 	 * @deprecated
@@ -438,6 +443,11 @@ export interface PartialExperimentsConfig {
 	 * @deprecated
 	 */
 	strictProjectAliases?: boolean | null;
+	/**
+	 * Disallow referencing the original ID of a renamed project when
+	 * building the project graph.
+	 */
+	strictProjectIds?: boolean | null;
 	/**
 	 * @default true
 	 * @deprecated

website/docs/config/workspace.mdx

@@ -301,6 +301,21 @@ docker:
 
 Enable or disable experiments that alter core functionality.
 
+### `strictProjectIds`<VersionLabel version="1.29.4" />
+
+<HeadingApiLink to="/api/types/interface/ExperimentsConfig#strictProjectIds" />
+
+When building the project graph, disallows referencing the original ID of a project (inferred from
+the folder name) when the project has been renamed to a new ID using the [`id`](./project#id)
+setting.
+
+Defaults to `false` but will be enabled to `true` in the future.
+
+```yaml title=".moon/workspace.yml" {1,2}
+experiments:
+  strictProjectIds: true
+```
+
 ## `extensions`<VersionLabel version="1.20.0" />
 
 <HeadingApiLink to="/api/types/interface/WorkspaceConfig#extensions" />

website/static/schemas/workspace.json

@@ -326,6 +326,11 @@
           "deprecated": true,
           "type": "boolean"
         },
+        "strictProjectIds": {
+          "title": "strictProjectIds",
+          "description": "Disallow referencing the original ID of a renamed project when building the project graph.",
+          "type": "boolean"
+        },
         "taskOutputBoundaries": {
           "title": "taskOutputBoundaries",
           "default": true,