Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/angular-compiler/src/lib/integration.spec.ts`:
- Around line 1675-1716: Add a focused spec that reproduces the regression where
an argument can be emitted as undefined so compilation doesn't crash: inside the
existing "emitExpr routing for function/method args" suite add a test that calls
a component method with an undefined argument (for example via a literal
`undefined` or a property that is `undefined`) in the template, compile it
(using the existing compile(...) helper) and assert the compilation succeeds
(expectCompiles(result)) and the generated output contains the expected call
site (e.g., 'ctx.format' or the method name), so this directly exercises the
emitExpr path changed in js-emitter.ts and guards against the undefined-arg
crash.
- Around line 1623-1650: Update the test that uses compile/expectCompiles for
HostComponent/ColorDirective to assert the aliased input/output names are
exposed, not just that "hostDirectives" exists: modify the hostDirectives object
in the test to use inputs: ['color: appColor'] and outputs: ['colorChange:
appColorChange'] and then assert the compiled result contains the aliased
identifiers (e.g. "appColor" and "appColorChange" or the specific generated
mapping for hostDirectives), so the normalization logic in compile for
inputs/outputs is validated.

In `@packages/angular-compiler/src/lib/metadata.ts`:
- Around line 181-199: The inputs/outputs parsing currently stores the raw
string; update the loop in metadata.ts (the blocks handling
prop.initializer.elements where inputs and outputs are populated) to parse
ts.isStringLiteral(e). For each e.text, if it contains a colon split on ':' and
trim both sides so you assign the directive property as the key and the public
alias as the value (e.g., let [dirProp, alias] = text.split(':').map(s =>
s.trim()); inputs![dirProp] = alias ?? dirProp), otherwise preserve the original
name for key and value; apply the same fix for outputs and add a unit test that
exercises an aliased binding like inputs: ['color: appColor'] to prevent
regressions.

---

Nitpick comments:
In `@packages/angular-compiler/src/lib/compile.ts`:
- Around line 791-818: The current hoisting loop in compile.ts moves all
non-exported post-class variable and function declarations, which can reorder
unrelated side effects; narrow this to only move variable declarations actually
referenced by Ivy initializers: use classResults to collect identifier names
used by the static ɵcmp/initializer code (or other classResults fields that
contain initializer AST/text), then when iterating origSourceFile.statements
only hoist ts.isVariableStatement stmts that declare one or more of those
referenced names (skip function declarations entirely since JS already hoists
them), using hasExportModifier to avoid exported symbols and
ms.appendLeft/ms.remove to perform the move; if selective hoisting cannot cover
all cases add a clear comment/commit note explaining why blanket hoisting is
required and document the risk to evaluation order.