Repository navigation
Divergences from ngtsc found by running Angular's ngtsc emit specs (non-functional) #623
Description
Summary
I ran Angular v22.0.0's own packages/compiler-cli/test/ngtsc/*_spec.ts emit tests against oxc main (04cb3b2, angularVersion 22.0.0). For each test, driveMain() was replaced with transformAngularFileSync. Of 527 tests that assert on emitted JS, 254 pass. This issue lists the remaining divergences that aren't runtime bugs, so they're tracked in one place. Items marked (known) are already in e2e/compare/fixtures/known-differences.ts.
Dev-mode only
| Divergence | ngtsc spec |
|---|---|
Signal APIs (signal, computed, input, model, linkedSignal, resource, httpResource, queries…) get no debugName (known) |
debug_transform_spec.ts (72 tests) |
ɵɵattachSourceLocations(...) never emitted (template source locations for DevTools) |
attach_source_location_spec.ts (4) |
forbidOrphanRendering: true missing from ɵsetClassDebugInfo when forbidOrphanComponents is set (no equivalent option) |
ngtsc_spec.ts "should set forbidOrphanRendering debug info…" (2) |
setClassMetadata uses type: i1.KeyCodes for a const enum ctor param, where ngtsc uses type: undefined |
ngtsc_spec.ts "should use undefined in setClassMetadata for const enums" |
Bundle size
| Divergence | ngtsc spec |
|---|---|
ɵɵsetNgModuleScope isn't guarded by ngJitMode (known, intentional) |
scope_spec.ts, ngtsc_spec.ts "should compile NgModules without errors" |
ɵɵdefineInjector({ imports }) keeps standalone directives and pipes (and NgModule-exported directives) that ngtsc filters out |
standalone_spec.ts "optimizations …" (4), ngtsc_spec.ts "InjectorDef emit optimizations…" (2), "should filter out directives and pipes from module exports in the injector def" |
schemas: [...] is emitted in ɵcmp/ɵmod; ngtsc drops it |
standalone_spec.ts "…with schema support", ngtsc_spec.ts "should not include schemas in component and module defs" |
Query predicates are inlined (ɵɵviewQuery(["test1"], 5)) instead of pooled constants (const _c0 = ["test1"]) |
ngtsc_spec.ts "should generate queries for directives" |
Identical inline styles across components in one file aren't shared through a _c0 constant |
ngtsc_spec.ts "inline resources should share same styles…" |
Different output, same runtime behaviour
- Dependencies use
ɵɵgetComponentDepsFactory(Cmp, imports)instead of the resolved list (known). This also accounts for thesetComponentScopecycle-detection tests. @deferloaders are inline arrows inɵɵdefer(i, j, () => [import(...)]). ngtsc emits a namedCmp_Defer_N_DepsFnconst that also lists eagerly available local deps, and() => [CmpA]when nothing is lazy. (defer_spec.ts, ~20 tests)- Constructors that can't be injected compile to
new C(ɵɵinvalidFactoryDep(n)), where ngtsc emitsɵɵinvalidFactory(). Both throw on instantiation, with different messages. (ngtsc_spec.ts"compiling invalid @Injectables/@Directives…",local_compilation_spec.ts"should generate invalid factory…", 16 tests) - Import shape:
- named imports are kept, where ngtsc re-emits
import * as i1; - no local-compilation side-effect imports (
import "./dep"); ModuleWithProvidersconstants aren't unwrapped (imports: [mwp]vs[i1.DepModule]);- default-imported tokens are emitted as
i1.default.
- named imports are kept, where ngtsc re-emits
Not applicable to oxc (for completeness)
.d.ts assertions in full mode, flat module index, Bazel/g3 alias re-exports (ɵngExportɵ…, _useHostForImportAndAliasGeneration), Closure annotations, compileNonExportedClasses, supportTestBed/supportJitMode: false.
Functional bugs found by the same run are filed separately; links in a comment below.
Activity
edbzn commentedon Oct 25, 2026
Functional bugs found by the same run, each with a fix:
@Attribute()outside components injected as a DI token: fix(compiler):@Attribute()on a directive/pipe/injectable/NgModule constructor compiles to a token inject (NullInjectorError) #624 → fix(compiler): inject@Attribute()params withɵɵinjectAttributeoutside components #625ɵɵinvalidFactoryDep: Constructor param typedns.Foo(namespace-qualified) compiles to ɵɵinvalidFactoryDep #633 → fix(di): inject constructor params typed with a namespace-qualified name #634deps: [[new Optional(), new Self(), Dep]]injects the array: @Injectable deps entries written as [new Optional(), new Self(), Dep] inject the array as the token #629 → fix(injectable): read flag arrays in useFactory/useClass deps #636preserveWhitespacesignored: Project-wide preserveWhitespaces option is ignored #631 → fix(component): apply the project-wide preserveWhitespaces option #637$localizemessages never carry legacy message ids (enableI18nLegacyMessageIdFormat) #628 → fix(i18n): emit legacy message ids underenableI18nLegacyMessageIdFormat#638@deferdoesn't lazy-load aforwardRef(() => X)import: @defer doesn't lazy-load an imports entry written as forwardRef(() => X) #632 → fix(defer): lazy-load an imports entry written as forwardRef(() => X) #640Brooooooklyn commentedon Oct 28, 2026
I re-checked every item on main
5780233against ngtsc 22.2.3, in full and partial mode.Fixed by an open PR
ɵɵinvalidFactoryDep(n)instead ofɵɵinvalidFactory()/deps: "invalid"schemasinɵmod(ɵcmpalready matched)i1.default(this one came from oxc, not ngtsc)@Inject(TOKEN)rewritten toi1.TOKEN(left over from the import-shape item)debugName(known)@deferloaders inline instead ofCmp_Defer_N_DepsFn, one shared fn for all blocks_c0(only strings of 50+ chars, as in ngtsc), and query predicates not shared across classesAlready matches ngtsc on main
import * as i1: ctor types, metadata, host directives and deps all match now.import "./dep"): ngtsc emits them only inexperimental-localwithgenerateExtraImportsInLocalMode.Still open
ɵɵattachSourceLocationsenableTemplateSourceLocationsoption. It is off by default in ngtsc, and the Angular CLI never sets it.forbidOrphanRenderingforbidOrphanComponentsoption. The Angular CLI doesn't set it either.const enumparam type insetClassMetadataconst enum. An imported one needs type info from another file.ɵɵdefineInjector({ imports })filteringModuleWithProvidersconstants not unwrappedɵɵgetComponentDepsFactory(known)ɵɵsetNgModuleScopewithout thengJitModeguard (known)ɵɵgetComponentDepsFactoryreads the scope at runtime.Runtime bugs found by the same re-check
@Pipedrops its constructor deps, and a partial class that inherits its constructor getsdeps: []: fix(partial): keep pipe ctor deps and inherited factories in ɵɵngDeclareFactory #656ɵɵinject(Foo), which throwsReferenceError: Constructor param typed by a same-file interface is injected as a token (ReferenceError at runtime) #653deferredImports: partial output never loads the block, and the 22.2 named form does not compile: deferredImports: partial output never loads the block, and the Angular 22.2 named form does not compile #654dependencies, so their directives never match: Partial mode: NgModule-declared components get no dependencies, so their directives never match #655fix(compiler): align five small emit shapes with ngtsc (#623) (#657)