fix: pool ng-content attributes into the const pool (v22) (#340)

* fix: pool ng-content attributes into the const pool (v22)

Angular 22.0.0 (rc.3, angular/angular@2891f7e) moves the `attrs` argument
of `ɵɵprojection` out of the inline call and into the shared const pool,
emitting `ɵɵprojection(slot, idx, _cN)` instead of an inline array. Mirror
that in const_collection by routing projection attrs through
`pool.get_const_literal(.., true)`, exactly as element attrs and the
projectionDef/ngContentSelectors consts already do. This phase runs after
generate_projection_def, so the projection attrs land at the next `_cN`,
matching the goldens.

Bump the conformance angular submodule rc.2 -> v22.0.0 so the suite guards
this emit. Conformance stays at 1264/1264 (100%); update the three
ng-content integration snapshots to the pooled form.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix: reuse pooled projection attrs const per xref

Co-authored-by: brandonroberts <42211+brandonroberts@users.noreply.github.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: openai-code-agent[bot] <242516109+Codex@users.noreply.github.com>
Co-authored-by: brandonroberts <42211+brandonroberts@users.noreply.github.com>

Author: 3 people

crates/oxc_angular_compiler/angular

@@ -760,15 +760,29 @@ pub fn collect_element_consts(job: &mut ComponentCompilationJob<'_>) {
     // Second pass (2b): Assign const indices in collected order
     // This is where we actually call add_const, matching Angular's getConstIndex call order
     let mut element_const_indices: FxHashMap<XrefId, u32> = FxHashMap::default();
-    let mut projection_attrs: FxHashMap<XrefId, OutputExpression<'_>> = FxHashMap::default();
+    let mut projection_attrs: FxHashMap<XrefId, Ident<'_>> = FxHashMap::default();
 
     for xref_item in &xrefs_to_assign {
         match xref_item {
             XrefToAssign::Projection(xref) => {
                 if let Some(attrs) = all_element_attrs.get(xref) {
                     if !attrs.is_empty() {
                         let attr_array = serialize_attributes_to_array_expr(allocator, attrs);
-                        projection_attrs.insert(*xref, attr_array);
+                        // Angular v22 (rc.3+) pools projection attributes into the
+                        // shared const pool (`_cN`) instead of emitting them inline,
+                        // matching `getConstLiteral(attrArray, true)` in Angular's
+                        // const_collection.ts (angular/angular@2891f7e). This phase
+                        // runs after `generate_projection_def`, so the projectionDef
+                        // and ngContentSelectors consts are pooled first and the
+                        // projection attrs land at the next `_cN`, as in the goldens.
+                        let pooled = job.pool.get_const_literal(attr_array, true);
+                        let pooled_name = match pooled {
+                            OutputExpression::ReadVar(rv) => rv.name.clone(),
+                            _ => unreachable!(
+                                "ConstantPool::get_const_literal must return OutputExpression::ReadVar"
+                            ),
+                        };
+                        projection_attrs.insert(*xref, pooled_name);
                     }
                 }
             }
@@ -794,8 +808,17 @@ pub fn collect_element_consts(job: &mut ComponentCompilationJob<'_>) {
             for op in view.create.iter_mut() {
                 match op {
                     CreateOp::Projection(proj) => {
-                        if let Some(attrs) = projection_attrs.remove(&proj.xref) {
-                            proj.attributes = Some(attrs);
+                        // It's possible for multiple projection ops to reference the same xref
+                        // (e.g. across conditional branches). Avoid consuming the pooled attrs so
+                        // every matching projection op receives the same const reference.
+                        if let Some(pooled_name) = projection_attrs.get(&proj.xref) {
+                            proj.attributes = Some(OutputExpression::ReadVar(Box::new_in(
+                                crate::output::ast::ReadVarExpr {
+                                    name: pooled_name.clone(),
+                                    source_span: None,
+                                },
+                                allocator,
+                            )));
                         }
                     }
                     CreateOp::ElementStart(elem) => {

crates/oxc_angular_compiler/src/pipeline/phases/const_collection.rs

@@ -3,9 +3,10 @@ source: crates/oxc_angular_compiler/tests/integration_test.rs
 expression: js
 ---
 const _c0 = ["*"];
+const _c1 = ["[select]","'[slot=expanded-content]'"];
 function TestComponent_Template(rf,ctx) {
   if ((rf & 1)) {
     i0.ɵɵprojectionDef();
-    i0.ɵɵprojection(0,0,["[select]","'[slot=expanded-content]'"]);
+    i0.ɵɵprojection(0,0,_c1);
   }
 }

crates/oxc_angular_compiler/tests/snapshots/integration_test__ng_content_with_bound_select.snap

@@ -3,9 +3,10 @@ source: crates/oxc_angular_compiler/tests/integration_test.rs
 expression: js
 ---
 const _c0 = ["*"];
+const _c1 = ["ngProjectAs","bit-label",5,["bit-label"]];
 function TestComponent_Template(rf,ctx) {
   if ((rf & 1)) {
     i0.ɵɵprojectionDef();
-    i0.ɵɵprojection(0,0,["ngProjectAs","bit-label",5,["bit-label"]]);
+    i0.ɵɵprojection(0,0,_c1);
   }
 }

crates/oxc_angular_compiler/tests/snapshots/integration_test__ng_content_with_ng_project_as.snap

@@ -3,9 +3,10 @@ source: crates/oxc_angular_compiler/tests/integration_test.rs
 expression: js
 ---
 const _c0 = ["*"];
+const _c1 = ["ngProjectAs","[card-content]",5,["","card-content",""]];
 function TestComponent_Template(rf,ctx) {
   if ((rf & 1)) {
     i0.ɵɵprojectionDef();
-    i0.ɵɵprojection(0,0,["ngProjectAs","[card-content]",5,["","card-content",""]]);
+    i0.ɵɵprojection(0,0,_c1);
   }
 }