This patch is one of the final patches to refactor the styling algorithm
to be more efficient, performant and less complex.
This patch enables sanitization support for map-based and prop-based
style bindings.
PR Close#30667
Prior to this change we processed binding expression (including bindings with pipes) in i18n attributes before we generate update instruction. As a result, slot offsets for pipeBind instructions were calculated incorrectly. Now we perform binding expression processing when we generate "update block" instructions, so offsets are calculated correctly.
PR Close#30573
Currently the `@angular/compiler-cli` compliance tests sometimes do
not throw an exception if the expected output does not match the
generated JavaScript output. This can happen for the following cases:
1. Expected code includes character that is not part of known alphabet
(e.g. `Δ` is still used in a new compliance test after rebasing a PR)
2. Expected code asserts that a string literal matches a string with
escaped quotes. e.g. expects `const $var$ = "\"quoted\"";`)
PR Close#30597
There is an encoding issue with using delta `Δ`, where the browser will attempt to detect the file encoding if the character set is not explicitly declared on a `<script/>` tag, and Chrome will find the `Δ` character and decide it is window-1252 encoding, which misinterprets the `Δ` character to be some other character that is not a valid JS identifier character
So back to the frog eyes we go.
```
__
/ɵɵ\
( -- ) - I am ineffable. I am forever.
_/ \_
/ \ / \
== == ==
```
PR Close#30546
Previously we defensively wrapped expressions in case they ran afoul of
precedence rules. For example, it would be easy to create the TS AST structure
Call(Ternary(a, b, c)), but might result in printed code of:
```
a ? b : c()
```
Whereas the actual structure we meant to generate is:
```
(a ? b : c)()
```
However the TypeScript renderer appears to be clever enough to provide
parenthesis as necessary.
This commit removes these defensive paraenthesis in the cases of binary
and ternary operations.
FW-1273
PR Close#30349
A structural directive can specify a template guard for an input, such that
the type of that input's binding can be narrowed based on the guard's return
type. Previously, such template guards could only be methods, of which an
invocation would be inserted into the type-check block (TCB). For `NgIf`,
the template guard narrowed the type of its expression to be `NonNullable`
using the following declaration:
```typescript
export declare class NgIf {
static ngTemplateGuard_ngIf<E>(dir: NgIf, expr: E): expr is NonNullable<E>
}
```
This works fine for usages such as `*ngIf="person"` but starts to introduce
false-positives when e.g. an explicit non-null check like
`*ngIf="person !== null"` is used, as the method invocation in the TCB
would not have the desired effect of narrowing `person` to become
non-nullable:
```typescript
if (NgIf.ngTemplateGuard_ngIf(directive, ctx.person !== null)) {
// Usages of `ctx.person` within this block would
// not have been narrowed to be non-nullable.
}
```
This commit introduces a new strategy for template guards to allow for the
binding expression itself to be used as template guard in the TCB. Now,
the TCB generated for `*ngIf="person !== null"` would look as follows:
```typescript
if (ctx.person !== null) {
// This time `ctx.person` will successfully have
// been narrowed to be non-nullable.
}
```
This strategy can be activated by declaring the template guard as a
property declaration with `'binding'` as literal return type.
See #30235 for an example where this led to a false positive.
PR Close#30248
Currently in Ivy `NgModule` registration happens when the class is declared, however this is inconsistent with ViewEngine and requires extra generated code. These changes remove the generated code for `registerModuleFactory`, pass the id through to the `ngModuleDef` and do the module registration inside `NgModuleFactory.create`.
This PR resolves FW-1285.
PR Close#30244
```
//packages/compiler-cli/test:ngc
//packages/compiler/test:test
```
This also address `node_modules` to the ignored paths for ngc compiler as otherwise the `ready` is never fired
Partially addresses #29785
PR Close#30146
Now that the dependent files and compilation scopes are being tracked in
the incremental state, we can skip analysing and emitting source files if
none of their dependent files have changed since the last compile.
The computation of what files (and their dependencies) are unchanged is
computed during reconciliation.
This commit also removes the previous emission skipping logic, since this
approach covers those cases already.
PR Close#30238
This is the final patch to migrate the Angular styling code to have a
smaller instruction set in preparation for the runtime refactor. All
styling-related instructions now work both in template and hostBindings
functions and do not use `element` as a prefix for their names:
BEFORE:
elementStyling()
elementStyleProp()
elementClassProp()
elementStyleMap()
elementClassMap()
elementStylingApply()
AFTER:
styling()
styleProp()
classProp()
styleMap()
classMap()
stylingApply()
PR Close#30318
This patch removes all host-specific styling instructions in favor of
using element-level instructions instead. Because of the previous
patches that made sure `select(n)` worked between styling calls, all
host level instructions are not needed anymore. This patch changes each
of those instruction calls to use any of the `elementStyling*`,
`elementStyle*` and `elementClass*` styling instructions instead.
PR Close#30336
This patch is one commit of many patches that will unify all styling instructions
across both template-level bindings and host-level bindings. This patch in particular
removes the `elementIndex` param because it is already set prior to each styling
instruction via the `select(n)` instruction.
PR Close#30313
Prior to this patch, the `select(n)` instruction would only be generated
when property bindings are encountered which meant that styling-related
bindings were skipped. This patch ensures that all styling-related bindings
(i.e. class and style bindings) are always prepended with a `select()`
instruction prior to being generated in AOT.
PR Close#30311
This patch breaks up the existing `elementStylingMap` into
`elementClassMap` and `elementStyleMap` instructions. It also breaks
apart `hostStlyingMap` into `hostClassMap` and `hostStyleMap`
instructions. This change allows for better tree-shaking and reduces
the complexity of the styling algorithm code for `[style]` and `[class]`
bindings.
PR Close#30293
Fixes `HostBinding` and `HostListener` declarations not being inherited from base classes that don't have an Angular decorator.
This PR resolves FW-1275.
PR Close#30158
- Extracts and documents code that will be common to interpolation instructions
- Ensures that binding indices are updated at the proper time during compilation
- Adds additional tests
Related #30011
PR Close#30129
ngtsc generates type constructors which infer the type of a directive based
on its inputs. Previously, a bug existed where this inference would fail in
the case of 'any' input values. For example, the inference of NgForOf fails
when an 'any' is provided, as it causes TypeScript to attempt to solve:
T[] = any
In this case, T gets inferred as {}, the empty object type, which is not
desirable.
The fix is to assign generic types in type constructors a default type of
'any', which TypeScript uses instead of {} when inference fails.
PR Close#30094
ngtsc previously could attempt to reuse the main ts.Program twice. This
occurred when template type-checking was enabled and then an incremental
build was performed. This breaks a TypeScript invariant - ts.Programs can
only be reused once.
The creation of the template type-checking program reuses the main program,
rendering it moot. Then, on the next incremental build the main program
would be subject to reuse again, which would crash inside TypeScript.
This commit fixes the issue by reusing the template type-checking program
from the previous run on the next incremental build. Since under normal
circumstances the files in the type-checking program aren't changed, this
should be just as fast.
Testing strategy: a test is added in the incremental_spec which validates
that program reuse with type-checking turned on does not crash the compiler.
Fixes#30079
PR Close#30090
Fixes view and content queries not being inherited in Ivy, if the base class hasn't been annotated with an Angular decorator (e.g. `Component` or `Directive`).
Also reworks the way the `ngBaseDef` is created so that it is added at the same point as the queries, rather than inside of the `Input` and `Output` decorators.
This PR partially resolves FW-1275. Support for host bindings will be added in a follow-up, because this PR is somewhat large as it is.
PR Close#30015
Prior to this commit, the check that verifies correct "id" field type was too strict and didn't allow `module.id` as @NgModule's "id" field value. This change adds a special handling for `module.id` and uses it as id of @NgModule if specified.
PR Close#30040
The compiler uses metadata to represent what it statically knows about
various expressions in a program. Occasionally, expressions in the program
for which metadata is extracted may contain sub-expressions which are not
representable in metadata. One such construct is an arrow function.
The compiler does not always need to understand such expressions completely.
For example, for a provider defined with `useValue`, the compiler does not
need to understand the value at all, only the outer provider definition. In
this case, the compiler employs a technique known as "expression lowering",
where it rewrites the provider expression into one that can be represented
in metadata. Chiefly, this involves extracting out the dynamic part (the
`useValue` expression) into an exported constant.
Lowering is applied through a heuristic, which considers the containing
statement as well as the field name of the expression.
Previously, this heuristic was not completely accurate in the case of
route definitions and the `loadChildren` field, which is lowered. If the
route definition using `loadChildren` existed inside a decorator invocation,
lowering was performed correctly. However, if it existed inside a standalone
variable declaration with an export keyword, the heuristic would conclude
that lowering was unnecessary. For ordinary providers this is true; however
the compiler attempts to fully understand the ROUTES token and thus even if
an array of routes is declared in an exported variable, any `loadChildren`
expressions within still need to be lowered.
This commit enables lowering of already exported variables under a limited
set of conditions (where the initializer expression is of a specific form).
This should enable the use of `loadChildren` in route definitions.
PR Close#30038
Previously, a template's context name would only be included in an embedded
template function if the element that the template was declared on has a
tag name. This is generally true for elements, except for `ng-content`
that does not have a tag name. By omitting the context name the compiler
could introduce duplicate template function names, which would fail at runtime.
This commit fixes the behavior by always including the context name in the
template function's name, regardless of tag name.
Resolves FW-1272
PR Close#30025
Fixes Ivy throwing an error because it tries to generate styling instructions for empty `style` and `class` bindings.
This PR resolves FW-1274.
PR Close#30024
Template type-checking is enabled by default in the View Engine compiler.
The feature in Ivy is not quite ready for this yet, so this flag will
temporarily control whether templates are type-checked in ngtsc.
The goal is to remove this flag after rolling out template type-checking in
google3 in Ivy mode, and making sure the feature is as compatible with the
View Engine implementation as possible.
Initially, the default value of the flag will leave checking disabled.
PR Close#29698
This commit adds support for template type-checking a pipe binding which
previously was not handled by the type-checking engine. In compatibility
mode, the arguments to transform() are not checked and the type returned
by a pipe is 'any'. In full type-checking mode, the transform() method's
type signature is used to check the pipe usage and infer the return type
of the pipe.
Testing strategy: TCB tests included.
PR Close#29698
The template type-checking engine previously would assemble a type-checking
program by inserting Type Check Blocks (TCBs) into existing user files. This
approach proved expensive, as TypeScript has to re-parse and re-type-check
those files when processing the type-checking program.
Instead, a far more performant approach is to augment the program with a
single type-checking file, into which all TCBs are generated. Additionally,
type constructors are also inlined into this file.
This is not always possible - both TCBs and type constructors can sometimes
require inlining into user code, particularly if bound generic type
parameters are present, so the approach taken is actually a hybrid. These
operations are inlined if necessary, but are otherwise generated in a single
file.
It is critically important that the original program also include an empty
version of the type-checking file, otherwise the shape of the two programs
will be different and TypeScript will throw away all the old program
information. This leads to a painfully slow type checking pass, on the same
order as the original program creation. A shim to generate this file in the
original program is therefore added.
Testing strategy: this commit is largely a refactor with no externally
observable behavioral differences, and thus no tests are needed.
PR Close#29698
Previously the template type-checking code only considered the metadata of
directive classes actually referenced in the template. If those directives
had base classes, any inputs/outputs/etc of the base classes were not
tracked when generating the TCB. This resulted in bindings to those inputs
being incorrectly attributed to the host component or element.
This commit uses the new metadata package to follow directive inheritance
chains and use the full metadata for a directive for TCB generation.
Testing strategy: Template type-checking tests included.
PR Close#29698
This commit adds registration of AOT compiled NgModules that have 'id'
properties set in their metadata. Such modules have a call to
registerNgModuleType() emitted as part of compilation.
The JIT behavior of this code is already in place.
This is required for module loading systems (such as g3) which rely on
getModuleFactory().
PR Close#29980
Previously, ngtsc would fail to resolve `forwardRef` calls if they
contained additional parenthesis or casts. This commit changes the
behavior to first unwrap the AST nodes to see past such insignificant
nodes, resolving the issue.
Fixes#29639
PR Close#29886
Prior to this change, element attributes annotated with i18n- prefix were removed from element attribute list and processed separately by i18n-specific logic. This behavior is causing issues with directive matching, since attributes are not present in the list of attrs for matching purposes. This commit updates i18n logic to retain attributes in the main attribute list, thus allowing directive matching logic to work correctly.
PR Close#29856
The `Δ` caused issue with other infrastructure, and we are temporarily
changing it to `ɵɵ`.
This commit also patches ts_api_guardian_test and AIO to understand `ɵɵ`.
PR Close#29850
So far using runtime i18n with ivy meant that you needed to use Closure and `goog.getMsg` (or a polyfill). This PR changes the compiler to output both closure & non-closure code, while the unused option will be tree-shaken by minifiers.
This means that if you use the Angular CLI with ivy and load a translations file, you can use i18n and the application will not throw at runtime.
For now it will not translate your application, but at least you can try ivy without having to remove all of your i18n code and configuration.
PR Close#28689
Currently in Ivy we pass both the raw and parsed selectors to the projectionDef instruction, because the parsed selectors are used to match most nodes, whereas the raw ones are used to match against nodes with the ngProjectAs attribute. The raw selectors add a fair bit of code that won't be used in most cases, because ngProjectAs is somewhat rare.
These changes rework the compiler not to output the raw selectors in the projectionDef, but to parse the selector in ngProjectAs and to store it on the TAttributes. The logic for matching has also been changed so that it matches the pre-parsed ngProjectAs selector against the list of projection selectors.
PR Close#29578
The defineInjector function specifies its providers and imports array to
be optional, so if no providers/imports are present these keys may be
omitted. This commit updates the compiler to only generate the keys when
necessary.
PR Close#29598
Prior to this change, a module's imports and exports would be used verbatim
as an injectors' imports. This is detrimental for tree-shaking, as a
module's exports could reference declarations that would then prevent such
declarations from being eligible for tree-shaking.
Since an injector actually only needs NgModule references as its imports,
we may safely filter out any declarations from the list of module exports.
This makes them eligible for tree-shaking once again.
PR Close#29598
Prior to this change, all module metadata would be included in the
`defineNgModule` call that is set as the `ngModuleDef` field of module
types. Part of the metadata is scope information like declarations,
imports and exports that is used for computing the transitive module
scope in JIT environments, preventing those references from being
tree-shaken for production builds.
This change moves the metadata for scope computations to a pure function
call that patches the scope references onto the module type. Because the
function is marked pure, it may be tree-shaken out during production builds
such that references to declarations and exports are dropped, which in turn
allows for tree-shaken any declaration that is not otherwise referenced.
Fixes#28077, FW-1035
PR Close#29598
Currently there is no support in ngtsc for imports of the form:
```
import * as core from `@angular/core`
export function forRoot(): core.ModuleWithProviders;
```
This commit modifies the `ReflectionHost.getImportOfIdentifier(id)`
method, so that it supports this kind of return type.
PR Close#27675
This commit introduces a mechanism for incremental compilation to the ngtsc
compiler.
Previously, incremental information was used in the construction of the
ts.Program for subsequent compilations, but was not used in ngtsc itself.
This commit adds an IncrementalState class, which tracks state between ngtsc
compilations. Currently, this supports skipping the TypeScript emit step
when the compiler can prove the contents of emit have not changed.
This is implemented for @Injectables as well as for files which don't
contain any Angular decorated types. These are the only files which can be
proven to be safe today.
See ngtsc/incremental/README.md for more details.
PR Close#29380
This commit adds support for compiling the same program repeatedly in a way
that's similar to how incremental builds work in a tool such as the CLI.
* support is added to the compiler entrypoint for reuse of the Program
object between compilations. This is the basis of the compiler's
incremental compilation model.
* support is added to wrap the CompilerHost the compiler creates and cache
ts.SourceFiles in between compilations.
* support is added to track when files are emitted, for assertion purposes.
* an 'exclude' section is added to the base tsconfig to prevent .d.ts
outputs from the first compilation from becoming inputs to any subsequent
compilations.
PR Close#29380
Currently, ngtsc decides to use remote scoping if the compilation of a
component may create a cyclic import. This happens if there are two
components in a scope (say, A and B) and A directly uses B. During
compilation of B ngtsc will then note that if B were to use A, a cycle would
be generated, and so it will opt to use remote scoping for B.
ngtsc already uses the R3TargetBinder to correctly track the imports that
are actually required, for future cycle tracking. This commit expands that
usage to not trigger remote scoping unless B actually does consume A in its
template.
PR Close#29404
Currently when building an Angular project with `ngtsc`
and `flatModuleOutFile` enabled, the Ngtsc build will fail
if there are multiple source files as root file names.
Ngtsc and NGC currently determine the entry-point for multiple
root file names by looking for files ending with `/index.ts`.
This functionality is technically deprecated, but still supported
and currently breaks on Windows as the root file names are not
guaranteed to be normalized POSIX-like paths.
In order to make this logic more reliable in the future, this commit
also switches the shim generators and entry-point logic to the branded
path types. This ensures that we don't break this in the future.
PR Close#29453
Previously, only directives and services with generic type parameters
would emit `any` as generic type when emitting Ivy metadata into .d.ts
files. Pipes can also have generic type parameters but did not emit
`any` for all type parameters, resulting in the omission of those
parameters which causes compilation errors.
This commit adds support for pipes with generic type arguments and emits
`any` as generic type in the Ivy metadata.
Fixes#29400
PR Close#29403
This patch is the first of a few patches which separates the
styling logic between template bindings (e.g. <div [style])
from host bindings (e.g. @HostBinding('style')). This patch
in particular introduces a series of host-specific styling
instructions and changes the existing set of template styling
instructions not to accept directives. The underyling code (which
communicates with the styling algorithm) still works as it did
before.
This PR also separates the styling instruction code into a separate
file and moves over all other instructions into an dedicated
instructions directory.
PR Close#29292
This fix is for a bug in the ngtsc PartialEvaluator, which statically
evaluates expressions.
Sometimes, evaluating a reference requires resolving a function which is
declared in another module, and thus no function body is available. To
support this case, the PartialEvaluator has the concept of a foreign
function resolver.
This allows the interpretation of expressions like:
const router = RouterModule.forRoot([]);
even though the definition of the 'forRoot' function has no body. In
ngtsc today, this will be resolved to a Reference to RouterModule itself,
via the ModuleWithProviders foreign function resolver.
However, the PartialEvaluator also associates any Identifiers in the path
of this resolution with the Reference. This is done so that if the user
writes
const x = imported.y;
'x' can be generated as a local identifier instead of adding an import for
'y'.
This was at the heart of a bug. In the above case with 'router', the
PartialEvaluator added the identifier 'router' to the Reference generated
(through FFR) to RouterModule.
This is not correct. References that result from FFR expressions may not
have the same value at runtime as they do at compile time (indeed, this is
not the case for ModuleWithProviders). The Reference generated via FFR is
"synthetic" in the sense that it's constructed based on a useful
interpretation of the code, not an accurate representation of the runtime
value. Therefore, it may not be legal to refer to the Reference via the
'router' identifier.
This commit adds the ability to mark such a Reference as 'synthetic', which
allows the PartialEvaluator to not add the 'router' identifier down the
line. Tests are included for both the PartialEvaluator itself as well as the
resultant buggy behavior in ngtsc overall.
PR Close#29387
Currently if an Angular library has multiple unnamed module re-exports, NGC will
generate incorrect metdata if the project is using the flat-module bundle option.
e.g.
_public-api.ts_
```ts
export * from '@mypkg/secondary1';
export * from '@mypkg/secondary2';
```
There are clearly two unnamed re-exports in the `public-api.ts` file. NGC right now
accidentally overwrites all previous re-exports with the last one. Resulting in the
generated metadata only containing a reference to `@mypkg/secondary2`.
This is problematic as it is common for primary library entry-points to have
multiple re-exports (e.g. Material re-exporting all public symbols; or flex-layout
exporting all public symbols from their secondary entry-points).
Currently Angular Material works around this issue by manually creating
a metadata file that declares the re-exports from all unnamed re-exports.
(see: https://github.com/angular/material2/blob/master/tools/package-tools/build-release.ts#L78-L85)
This workaround works fine currently, but is no longer easily integrated when
building the package output with Bazel. In order to be able to build such
libraries with Bazel (Material/flex-layout), we need to make sure that NGC
generates the proper flat-module metadata bundle.
PR Close#29360
Previously, ngtsc would resolve forward references while evaluating the
bootstrap, declaration, imports, and exports fields of NgModule types.
However, when generating the resulting ngModuleDef, the forward nature of
these references was not taken into consideration, and so the generated JS
code would incorrectly reference types not yet declared.
This commit fixes this issue by introducing function closures in the
NgModuleDef type, similarly to how NgComponentDef uses them for forward
declarations of its directives and pipes arrays. ngtsc will then generate
closures when required, and the runtime will unwrap them if present.
PR Close#29198
This fixes an issue with commit b6f6b117. In this commit, default imports
processed in a type-to-value conversion were recorded as non-local imports
with a '*' name, and the ImportManager generated a new default import for
them. When transpiled to ES2015 modules, this resulted in the following
correct code:
import i3 from './module';
// somewhere in the file, a value reference of i3:
{type: i3}
However, when the AST with this synthetic import and reference was
transpiled to non-ES2015 modules (for example, to commonjs) an issue
appeared:
var module_1 = require('./module');
{type: i3}
TypeScript renames the imported identifier from i3 to module_1, but doesn't
substitute later references to i3. This is because the import and reference
are both synthetic, and never went through the TypeScript AST step of
"binding" which associates the reference to its import. This association is
important during emit when the identifiers might change.
Synthetic (transformer-added) imports will never be bound properly. The only
possible solution is to reuse the user's original import and the identifier
from it, which will be properly downleveled. The issue with this approach
(which prompted the fix in b6f6b117) is that if the import is only used in a
type position, TypeScript will mark it for deletion in the generated JS,
even though additional non-type usages are added in the transformer. This
again would leave a dangling import.
To work around this, it's necessary for the compiler to keep track of
identifiers that it emits which came from default imports, and tell TS not
to remove those imports during transpilation. A `DefaultImportTracker` class
is implemented to perform this tracking. It implements a
`DefaultImportRecorder` interface, which is used to record two significant
pieces of information:
* when a WrappedNodeExpr is generated which refers to a default imported
value, the ts.Identifier is associated to the ts.ImportDeclaration via
the recorder.
* when that WrappedNodeExpr is later emitted as part of the statement /
expression translators, the fact that the ts.Identifier was used is
also recorded.
Combined, this tracking gives the `DefaultImportTracker` enough information
to implement another TS transformer, which can recognize default imports
which were used in the output of the Ivy transform and can prevent them
from being elided. This is done by creating a new ts.ImportDeclaration for
the imports with the same ts.ImportClause. A test verifies that this works.
PR Close#29266
Prior to this change default selector for Components was not applied in case selector is missing or defined as an empty string. This update aligns this behavior between Ivy and VE: now default selector is used for Components when it's needed. Directives with empty selector are not allowed and trigger a compile-time error in both Ivy and VE.
PR Close#29239
Prior to this change the code didn't take into account the fact that decorators can be aliases while importing into a script. As a result, these decorators were not recognized by Angular and various failures happened because of that. Now we take aliases into account and resolve decorator name properly.
PR Close#29195
ngsummary files were generated with an export for each class declaration.
However, some Angular code declares classes (class Foo) and exports them
(export {Foo}) separately, which was causing incomplete summary files.
This commit expands the set of symbol names for which summary exports will
be generated, fixing this issue.
PR Close#29193
Previously, when the NgModule scope resolver discovered semantic errors
within a users NgModules, it would throw assertion errors. TODOs in the
codebase indicated these should become ts.Diagnostics eventually.
Besides producing better-looking errors, there is another reason to make
this change asap: these assertions were shadowing actual errors, via an
interesting mechanism:
1) a component would produce a ts.Diagnostic during its analyze() step
2) as a result, it wouldn't register component metadata with the scope
resolver
3) the NgModule for the component references it in exports, which was
detected as an invalid export (no metadata registering it as a
component).
4) the resulting assertion error would crash the compiler, hiding the
real cause of the problem (an invalid component).
This commit should mitigate this problem by converting scoping errors to
proper ts.Diagnostics. Additionally, we should consider registering some
marker indicating a class is a directive/component/pipe without actually
requiring full metadata to be produced for it, which would allow suppression
of errors like "invalid export" for such invalid types.
PR Close#29191
At the moment, certain tests relies on resolving the module with an index.d.ts, this root cause might be some implementations are missing from the mocks.
Similar to: 58b4045359
PR Close#28884
This commit refactors and expands ngtsc's support for generating imports of
values from imports of types (this is used for example when importing a
class referenced in a type annotation in a constructor).
Previously, this logic handled "import {Foo} from" and "import * as foo
from" style imports, but failed on imports of default values ("import
Foo from"). This commit moves the type-to-value logic to a separate file and
expands it to cover the default import case. Doing this also required
augmenting the ImportManager to track default as well as non-default import
generation. The APIs were made a little cleaner at the same time.
PR Close#29146
Prior to this commit, i18n instructions (i18n, i18nStart) were generated before listener instructions. As a result, event listeners were attached to the wrong element (text node, not the parent element). This change updates the order of instructions and puts i18n ones after listeners, to make sure listeners are attached to the right elements.
PR Close#29173
The content projection mechanism is static, in that it only looks at the static
template nodes before directives are matched and change detection is run.
When you have a selector-based content projection the selection is based
on nodes that are available in the template.
For example:
```
<ng-content selector="[some-attr]"></ng-content>
```
would match
```
<div some-attr="..."></div>
```
If you have an inline-template in your projected nodes. For example:
```
<div *ngIf="..." some-attr="..."></div>
```
This gets pre-parsed and converted to a canonical form.
For example:
```
<ng-template [ngIf]="...">
<div some-attr=".."></div>
</ng-template>
```
Note that only structural attributes (e.g. `*ngIf`) stay with the `<ng-template>`
node. The other attributes move to the contained element inside the template.
When this happens in ivy, the ng-template content is removed
from the component template function and is compiled into its own
template function. But this means that the information about the
attributes that were on the content are lost and the projection
selection mechanism is unable to match the original
`<div *ngIf="..." some-attr>`.
This commit adds support for this in ivy. Attributes are separated into three
groups (Bindings, Templates and "other"). For inline-templates the Bindings
and "other" types are hoisted back from the contained node to the `template()`
instruction, so that they can be used in content projection matching.
PR Close#29041
Prior to this change, the RegExp that was used to check for dashes in field names used "g" (global) flag that retains lastIndex, which might result in skipping some fields that should be wrapped in quotes (since lastIndex advanced beyond the next "-" location). This commit removes this flag and updates the test to make sure there are no regressions.
PR Close#29126
ngtsc occasionally converts a type reference (such as the type of a
parameter in a constructor) to a value reference (argument to a
directiveInject call). TypeScript has a bad habit of sometimes removing
the import statement associated with this type reference, because it's a
type only import when it initially looks at the file.
A solution to this is to always add an import to refer to a type position
value that's imported, and not rely on the existing import.
PR Close#29111
When ngtsc generates a .ngfactory shim, it does so based on the contents of
an original file in the program. Occasionally these original files have
comments at the top which are load-bearing (e.g. they contain jsdoc
annotations which are significant to downstream bundling tools). The
generated factory shims should preserve this comment.
This commit adds a step to the ngfactory generator to preserve the top-level
comment from the original source file.
FW-1006 #resolve
FW-1095 #resolve
PR Close#29065
Prior to this change, keys in "inputs" and "outputs" objects generated by compiler were not checked against unsafe characters. As a result, in some cases the generated code was throwing JS error. Now we check whether a given key contains any unsafe chars and wrap it in quotes if needed.
PR Close#28919
Currently, ngtsc has a bug where if you alias the name of a decorator when
importing it, it won't be detected properly. This is because the compiler
uses the aliased name and not the original, declared name of the decorator
for detection.
This commit fixes the compiler to compare against the declared name of
decorators when available, and adds a test to prevent regression.
PR Close#29061
ngtsc has cyclic import detection, to determine when adding an import to a
directive or pipe would create a cycle. However, this detection must also
account for already inserted imports, as it's possible for both directions
of a circular import to be inserted by Ivy (as opposed to at least one of
those edges existing in the user's program).
This commit fixes the circular import detection for components to take into
consideration already added edges. This is difficult for one critical
reason: only edges to files which will *actually* be imported should be
considered. However, that depends on which directives & pipes are used in
a given template, which is currently only known by running the
TemplateDefinitionBuilder during the 'compile' phase. This is too late; the
decision whether to use remote scoping (which consults the import graph) is
made during the 'resolve' phase, before any compilation has taken place.
Thus, the only way to correctly consider synthetic edges is for the compiler
to know exactly which directives & pipes are used in a template during
'resolve'. There are two ways to achieve this:
1) refactor `TemplateDefinitionBuilder` to do its work in two phases, with
directive matching occurring as a separate step which can be performed
earlier.
2) use the `R3TargetBinder` in the 'resolve' phase to independently bind the
template and get information about used directives.
Option 1 is ideal, but option 2 is currently used for practical reasons. The
cost of binding the template can be shared with template-typechecking.
PR Close#29040
In the @Component decorator, the 'host' field is an object which represents
host bindings. The type of this field is complex, but is generally of the
form {[key: string]: string}. Several different kinds of bindings can be
specified, depending on the structure of the key.
For example:
```
@Component({
host: {'[prop]': 'someExpr'}
})
```
will bind an expression 'someExpr' to the property 'prop'. This is known to
be a property binding because of the square brackets in the binding key.
If the binding key is a plain string (no brackets or parentheses), then it
is known as an attribute binding. In this case, the right-hand side is not
interpreted as an expression, but is instead a constant string.
There is no actual requirement that at build time, these constant strings
are known to the compiler, but this was previously enforced as a side effect
of requiring the binding expressions for property and event bindings to be
statically known (as they need to be parsed). This commit breaks that
relationship and allows the attribute bindings to be dynamic. In the case
that they are dynamic, the references to the dynamic values are reflected
into the Ivy instructions for attribute bindings.
PR Close#29033
Prior to this change, TypeScript stripped out some imports in case we reference a type that can be represented as a value (for ex. classes). This fix ensures that we use correct symbol identifier, which makes TypeScript retain the necessary import statements.
PR Close#28941
Angular supports using <style> and <link> tags inline in component
templates, but previously such tags were not implemented within the ngtsc
compiler. This commit introduces that support.
FW-1069 #resolve
PR Close#28997
Prior to this change i18n block bindings were converted to Expressions right away (once we first access them), when in non-i18n cases we processed them differently: the actual conversion happens at instructions generation. Because of this discrepancy, the output for bindings in i18n blocks was generated incorrectly (with invalid indicies in pipeBindN fns and invalid references to non-existent local variables). Now the bindings processing is unified and i18nExp instructions should contain right bind expressions.
PR Close#28969
Prior to this change, the logic that outputs i18n consts (like `const MSG_XXX = goog.getMsg(...)`) didn't have a check whether a given const that represent a certain i18n message was already included into the generated output. This commit adds the logic to mark corresponding i18n contexts after translation was generated, to avoid duplicate consts in the output.
PR Close#28967
In certain configurations (such as the g3 repository) which have lots of
small compilation units as well as strict dependency checking on generated
code, ngtsc's default strategy of directly importing directives/pipes into
components will not work. To handle these cases, an additional mode is
introduced, and is enabled when using the FileToModuleHost provided by such
compilation environments.
In this mode, when ngtsc encounters an NgModule which re-exports another
from a different file, it will re-export all the directives it contains at
the ES2015 level. The exports will have a predictable name based on the
FileToModuleHost. For example, if the host says that a directive Foo is
from the 'root/external/foo' module, ngtsc will add:
```
export {Foo as ɵng$root$external$foo$$Foo} from 'root/external/foo';
```
Consumers of the re-exported directive will then import it via this path
instead of directly from root/external/foo, preserving strict dependency
semantics.
PR Close#28852
This commit splits apart selector_scope.ts in ngtsc and extracts the logic
into two separate classes, the LocalModuleScopeRegistry and the
DtsModuleScopeResolver. The logic is cleaned up significantly and new tests
are added to verify behavior.
LocalModuleScopeRegistry implements the NgModule semantics for compilation
scopes, and handles NgModules declared in the current compilation unit.
DtsModuleScopeResolver implements simpler logic for export scopes and
handles NgModules declared in .d.ts files.
This is done in preparation for the addition of re-export logic to solve
StrictDeps issues.
PR Close#28852
Prior to this change presence of HTML comments inside <ng-content> caused compiler to throw an error that <ng-content> is not empty. Now HTML comments are not considered as a meaningful content, thus no error is thrown. This behavior is now aligned in Ivy/VE.
PR Close#28849
Prior to this change absolute file paths (like `/a/b/c/style.css`) were calculated taking current component file location into account. As a result, absolute file paths were calculated using current file as a root. This change updates this logic to ignore current file path in case of absolute paths.
PR Close#28789
Prior to this change, Ivy and VE CSS resource resolution was different: in addition to specified styleUrl (with .scss, .less and .styl extensions), VE also makes an attempt to resolve resource with .css extension. This change introduces similar logic for Ivy to make sure Ivy behavior is backwards compatible.
PR Close#28770
Prior to this change, the @fileoverview annotations added by users in source files or by tsickle during compilation might have change a location due to the fact that Ngtsc may prepend extra imports or constants. As a result, the output file is considered invalid by Closure (misplaced @fileoverview annotation). In order to resolve the problem we relocate @fileoverview annotation if we detect that its host node shifted.
PR Close#28723
This change is kind of similar to #27466, but instead of ensuring that
these shims can be generated, we also need to make sure that developers
are able to also use the factory shims like with `ngc`.
This issue is now surfacing because we have various old examples which
are now also built with `ngtsc` (due to the bazel migration). On case insensitive
platforms (e.g. windows) these examples cannot be built because ngtsc fails
the app imports a generated shim file (such as the factory shim files).
This is because the `GeneratedShimsHostWrapper` TypeScript host uses
the `getCanonicalFileName` method in order to check whether a given
file/module exists in the generator file maps. e.g.
```
// Generator Map:
'C:/users/paul/_bazel_paul/lm3s4mgv/execroot/angular/packages/core/index.ngfactory.ts' =>
'C:/users/paul/_bazel_paul/lm3s4mgv/execroot/angular/packages/core/index.ts',
// Path passed into `fileExists`
C:/users/paul/_bazel_paul/lm3s4mgv/execroot/angular/packages/core/index.ngfactory.ts
// After getCanonicalFileName (notice the **lower-case drive name**)
c:/users/paul/_bazel_paul/lm3s4mgv/execroot/angular/packages/core/index.ngfactory.ts
```
As seen above, the generator map does not use the canonical file names, as well as
TypeScript internally does not pass around canonical file names. We can fix this by removing
the manual call to `getCanonicalFileName` and just following TypeScript internal-semantics.
PR Close#28831
Fixes a minor typo in the `listLazyRoutes` method for `ngtsc`. Also in
addition fixes that a newly introduced test for `listLazyRoutes` broke the
tests in Windows. It's clear that we still don't run tests against
Windows, but we also made all other tests pass (without CI verification),
and it's not a big deal fixing this while being at it.
PR Close#28831
Prior to this fix, using the compiler's ivy_switch mechanism was
only available to core packages. This patch allows for this variable
switching mechanism to work across all other angular packages.
PR Close#28711
This commit adds support for the `static: true` flag in `ContentChild`
queries. Prior to this commit, all `ContentChild` queries were resolved
after change detection ran. This is a problem for backwards
compatibility because View Engine also supported "static" queries which
would resolve before change detection.
Now if users add a `static: true` option, the query will be resolved in
creation mode (before change detection runs). For example:
```ts
@ContentChild(TemplateRef, {static: true}) template !: TemplateRef;
```
This feature will come in handy for components that need
to create components dynamically.
PR Close#28811
This commit adds support for the `static: true` flag in
`ViewChild` queries. Prior to this commit, all `ViewChild`
queries were resolved after change detection ran. This is
a problem for backwards compatibility because View Engine
also supported "static" queries which would resolve before
change detection.
Now if users add a `static: true` option, the query will be
resolved in creation mode (before change detection runs).
For example:
```ts
@ViewChild(TemplateRef, {static: true}) template !: TemplateRef;
```
This feature will come in handy for components that need
to create components dynamically.
PR Close#28811
Currently if developers use call expressions in their static
class members ([like we do in Angular](https://github.com/angular/angular/blob/master/packages/core/src/change_detection/differs/keyvalue_differs.ts#L121)),
the metadata that is generated for flat modules is invalid. This
is because the metadata bundler logic currently does not handle
call expressions in static class members and the symbol references
are not rewritten to avoid relative paths in the bundle.
Static class members using a call expression are not relevant for
the ViewEngine AOT compilation, but it is problematic that the
bundled metadata references modules using their original relative
path. This means that the bundled metadata is no longer encapsulated
and depends on other emitted files to be emitted in the proper place.
These incorrect relative paths can now cause issues where NGC
looks for the referenced symbols in the incorrect path. e.g.
```
src/
| lib/
| index.ts -> References the call expression using `../../di`
```
Now the metadata looks like that:
```
node_modules/
| @angular/
-- | core/
-- -- | core.metadata.json -> Says that the call expr. is in `../../di`.
| di/
```
Now if NGC tries to use the metadata files and create the summary files,
NGC resolves the call expression to the `node_modules/di` module. Since
the "unexpected" module does not contain the desired symbol, NGC will
error out.
We should fix this by ensuring that we don't ship corrupted metadata
to NPM which contains relative references that can cause such
failures (other imports can be affected as well; it depends on what
modules the developer has installed and how we import our call
expressions).
Fixes#28741.
PR Close#28762
Currently setting `enableIvy` to true runs a hybrid mode of `ngc` and `ngtsc`. This is counterintuitive given the name of the flag itself.
This PR makes the `true` value equivalent to the previous `ngtsc`, and `ngtsc` becomes an alias for `true`. Effectively this removes the hybrid mode as well since there's no other way to enable it.
PR Close#28616
Previously, ngtsc would throw an error if two decorators were matched on
the same class simultaneously. However, @Injectable is a special case, and
it appears frequently on component, directive, and pipe classes. For pipes
in particular, it's a common pattern to treat the pipe class also as an
injectable service.
ngtsc actually lacked the capability to compile multiple matching
decorators on a class, so this commit adds support for that. Decorator
handlers (and thus the decorators they match) are classified into three
categories: PRIMARY, SHARED, and WEAK.
PRIMARY handlers compile decorators that cannot coexist with other primary
decorators. The handlers for Component, Directive, Pipe, and NgModule are
marked as PRIMARY. A class may only have one decorator from this group.
SHARED handlers compile decorators that can coexist with others. Injectable
is the only decorator in this category, meaning it's valid to put an
@Injectable decorator on a previously decorated class.
WEAK handlers behave like SHARED, but are dropped if any non-WEAK handler
matches a class. The handler which compiles ngBaseDef is WEAK, since
ngBaseDef is only needed if a class doesn't otherwise have a decorator.
Tests are added to validate that @Injectable can coexist with the other
decorators and that an error is generated when mixing the primaries.
PR Close#28523
In the past, @Injectable had no side effects and existing Angular code is
therefore littered with @Injectable usage on classes which are not intended
to be injected.
A common example is:
@Injectable()
class Foo {
constructor(private notInjectable: string) {}
}
and somewhere else:
providers: [{provide: Foo, useFactory: ...})
Here, there is no need for Foo to be injectable - indeed, it's impossible
for the DI system to create an instance of it, as it has a non-injectable
constructor. The provider configures a factory for the DI system to be
able to create instances of Foo.
Adding @Injectable in Ivy signifies that the class's own constructor, and
not a provider, determines how the class will be created.
This commit adds logic to compile classes which are marked with @Injectable
but are otherwise not injectable, and create an ngInjectableDef field with
a factory function that throws an error. This way, existing code in the wild
continues to compile, but if someone attempts to use the injectable it will
fail with a useful error message.
In the case where strictInjectionParameters is set to true, a compile-time
error is thrown instead of the runtime error, as ngtsc has enough
information to determine when injection couldn't possibly be valid.
PR Close#28523
Translation of WriteKeyExpr expressions was not implemented in the ngtsc
expression translator. This resulted in binding expressions like
"target[key] = $event" not compiling.
This commit fixes the bug by implementing WriteKeyExpr translation.
PR Close#28523
Some applications use enum values in their host bindings:
@Component({
host: {
'[prop]': EnumType.Key,
}, ...
})
This commit changes the resolution of host properties to follow the enum
declaration and extract the correct value for the binding.
PR Close#28523
Testing of Ivy revealed two bugs in the AstMemoryEfficientTransformer
class, a part of existing View Engine compiler infrastructure that's
reused in Ivy. These bugs cause AST expressions not to be transformed
under certain circumstances.
The fix is simple, and tests are added to ensure the specific expression
forms that trigger the issue compile properly under Ivy.
PR Close#28523
Prior to this update we had separate contentQueries and contentQueriesRefresh functions to handle creation and update phases. This approach was inconsistent with View Queries, Host Bindings and Template functions that we generate for Component/Directive defs. Now the mentioned 2 functions are combines into one (contentQueries), creation and update logic is separated with RenderFlags (similar to what we have in other generated functions).
PR Close#28503
With #28594 we refactored the `@angular/compiler` slightly to
allow opting out from external symbol re-exports which are
enabled by default.
Since symbol re-exports only benefit projects which have a
very strict dependency enforcement, external symbols should
not be re-exported by default as this could grow the size of
factory files and cause unexpected behavior with Angular's
AOT symbol resolving (e.g. see: #25644).
Note that the common strict dependency enforcement for source
files does still work with external symbol re-exports disabled,
but there are also strict dependency checks that enforce strict
module dependencies also for _generated files_ (such as the
ngfactory files). This is how Google3 manages it's dependencies
and therefore external symbol re-exports need to be enabled within
Google3.
Also "ngtsc" also does not provide any way of using external symbol
re-exports, so this means that with this change, NGC can partially
match the behavior of "ngtsc" then (unless explicitly opted-out).
As mentioned before, internally at Google symbol re-exports need to
be still enabled, so the `ng_module` Bazel rule will enable the symbol
re-exports by default when running within Blaze.
Fixes#25644.
PR Close#28633
Previously, using a pipe in an input binding on an ng-template would
evaluate the pipe in the context of node that was processed before the
template. This caused the retrieval of e.g. ChangeDetectorRef to be
incorrect, resulting in one of the following bugs depending on the
template's structure:
1. If the template was at the root of a view, the previously processed
node would be the component's host node outside of the current view.
Accessing that node in the context of the current view results in a crash.
2. For templates not at the root, the ChangeDetectorRef injected into the
pipe would correspond with the previously processed node. If that node
hosts a component, the ChangeDetectorRef would not correspond with the
view that the ng-template is part of.
The solution to the above problem is two-fold:
1. Template compilation is adjusted such that the template instruction
is emitted before any instructions produced by input bindings, such as
pipes. This ensures that pipes are evaluated in the context of the
template's container node.
2. A ChangeDetectorRef can be requested for container nodes.
Fixes#28587
PR Close#27565
During analysis, the `ComponentDecoratorHandler` passes the component
template to the `parseTemplate()` function. Previously, there was little or
no information about the original source file, where the template is found,
passed when calling this function.
Now, we correctly compute the URL of the source of the template, both
for external `templateUrl` and in-line `template` cases. Further in the
in-line template case we compute the character range of the template
in its containing source file; *but only in the case that the template is
a simple string literal*. If the template is actually a dynamic value like
an interpolated string or a function call, then we do not try to add the
originating source file information.
The translator that converts Ivy AST nodes to TypeScript now adds these
template specific source mappings, which account for the file where
the template was found, to the templates to support stepping through the
template creation and update code when debugging an Angular application.
Note that some versions of TypeScript have a bug which means they cannot
support external template source-maps. We check for this via the
`canSourceMapExternalTemplates()` helper function and avoid trying to
add template mappings to external templates if not supported.
PR Close#28055
This commit consolidates the options that can modify the
parsing of text (e.g. HTML, Angular templates, CSS, i18n)
into an AST for further processing into a single `options`
hash.
This makes the code cleaner and more readable, but also
enables us to support further options to parsing without
triggering wide ranging changes to code that should not
be affected by these new options. Specifically, it will let
us pass information about the placement of a template
that is being parsed in its containing file, which is essential
for accurate SourceMap processing.
PR Close#28055
I don't know of any use of this API with a project-root-relative path
(i.e. the cli will always call it with an absolute path), but keeping
the API backwards compatible just in case.
PR Close#28542
Up until now, `[style]` and `[class]` bindings (the map-based ones) have only
worked as template bindings and have not been supported at all inside of host
bindings. This patch ensures that multiple host binding sources (components and
directives) all properly assign style values and merge them correctly in terms
of priority.
Jira: FW-882
PR Close#28246
Previously, it wasn't possible to compile template that contains pipe in context of ternary operator `{{ 1 ? 2 : 0 | myPipe }}` due to the error `Error: Illegal state: Pipes should have been converted into functions. Pipe: async`.
This PR fixes a typo in expression parser so that pipes are correctly converted into functions.
PR Close#28635
Prior to this change in Ivy we had strict check that disabled non-unique #localRefs usage within a given template. While this limitation was technically present in View Engine, in many cases View Engine neglected this restriction and as a result, some apps relied on a fact that multiple non-unique #localRefs can be defined and utilized to query elements via @ViewChild(ren) and @ContentChild(ren). In order to provide better compatibility with View Engine, this commit removes existing restriction.
As a part of this commit, are few tests were added to verify VE and Ivy compatibility in most common use-cases where multiple non-unique #localRefs were used.
PR Close#28627
Prior to this change there was no i18n id sanitization before we output goog.getMsg calls. Due to the fact that message ids are used as a part of const names, some characters were bcausing issues while executing generated code. This commit adds sanitization to i18n ids used to generate i18n-related consts.
PR Close#28522
Note that this fixes `compiler-cli` tests within `compiler-cli/test`,
but there seem to be remaining `ngcc` tests within `compiler-cli/src`
which aren't working on Windows. This is out-of-scope for this commit.
PR Close#28352
Currently the "ngtsc` testing helpers resolve the `fake_core` NPM
package using the `TEST_SRCDIR` variable. This is problematic on Windows
where Bazel runfiles are not symlinked into the runfiles directory.
In order to properly resolve the NPM Bazel tree artifact, we use the
`resolveTreeNpmArtifact` runfile helper that properly resolves the artifact
properly on all platforms.
PR Close#28352
In order to support running "compiler-cli" tests that use the "test_support.ts"
utilities on Windows with Bazel, we need to imporve the logic that resolves NPM
packages and symlinks them into a temporary directory.
A more Bazel idiomatic and windows compatible way of resolving Bazel runfiles
is to use the "RUNFILES_MANIFEST" if present. This ensures that the NPM
packages can be also symlinked on Windows, and tests can execute properly
on Windows. Read more about why this is needed here:
* https://github.com/bazelbuild/bazel/issues/3726#issue-257062364
PR Close#28352
Since we recently removed the `test.sh` script, and now run
all tests with Bazel, we can remove the unused logic that makes
compiler-cli tests pass in non-Bazel.
This cleans up the tests, and also makes it easier to write tests
without worrying about two ways of the Angular package output
(Bazel `ng_package` rules vs. old `build.sh` logic of building)
PR Close#28352
In View Engine, we supported @Input and @ContentChild annotations
on the same property. This feature was somewhat brittle because
it would only work for static queries, so it would break if a
content child was passed in wrapped in an *ngIf. Due to the
inconsistent behavior and low usage both internally and externally,
we will likely be deprecating it in the next version, and it does
not make sense to perpetuate it in Ivy.
This commit ensures that we now throw in Ivy if we encounter the
two annotations on the same property.
PR Close#28415
Prior to this change we may encounter some errors (like pipes being used where they should not be used) while compiling Host Bindings and Listeners. With this update we move validation logic to the analyze phase and throw an error if something is wrong. This also aligns error messages between Ivy and VE.
PR Close#28356
The TypeTranslatorVisitor visitor returned strings because before it wasn't possible to transform declaration files directly through the TypeScript custom transformer API.
Now that's possible though, so it should return nodes instead.
PR Close#28342
The current DtsFileTransformer works by intercepting file writes and editing the source string directly.
This PR refactors it as a afterDeclaration transform in order to fit better in the TypeScript API.
This is part of a greater effort of converting ngtsc to be usable as a TS transform plugin.
PR Close#28342
Prior to this change contentQueriesRefresh functions that represent refresh logic for @ContentQuery list were not composable, which caused problems in case one Directive inherits another one and both of them contain Content Queries. Due to the fact that we used indices to reference queries in refresh function, results were placed into wrong Queries. In order to avoid that we no longer use indices to reference queries and instead maintain current content query index while iterating through them. This allows us to compose contentQueriesRefresh functions and make inheritance feature work with Content Queries.
PR Close#28324
Currently `compileNgModule` generates an empty array for optional fields that are omitted from an `NgModule` declaration (e.g. `bootstrap`, `exports`). This isn't necessary, because `defineNgModule` has some code to default these fields to empty arrays at runtime if they aren't defined. The following changes will only output code if there are values for the particular field.
PR Close#28387
By its nature, Ivy alters the import graph of a TS program, adding imports
where template dependencies exist. For example, if ComponentA uses PipeB
in its template, Ivy will insert an import of PipeB into the file in which
ComponentA is declared.
Any insertion of an import into a program has the potential to introduce a
cycle into the import graph. If for some reason the file in which PipeB is
declared imports the file in which ComponentA is declared (maybe it makes
use of a service or utility function that happens to be in the same file as
ComponentA) then this could create an import cycle. This turns out to
happen quite regularly in larger Angular codebases.
TypeScript and the Ivy runtime have no issues with such cycles. However,
other tools are not so accepting. In particular the Closure Compiler is
very anti-cycle.
To mitigate this problem, it's necessary to detect when the insertion of
an import would create a cycle. ngtsc can then use a different strategy,
known as "remote scoping", instead of directly writing a reference from
one component to another. Under remote scoping, a function
'setComponentScope' is called after the declaration of the component's
module, which does not require the addition of new imports.
FW-647 #resolve
PR Close#28169
Prior to this change the postprocess step relied on the order of placeholders combined in one group (e.g. [�#1�|�*1:1�]). The order is not guaranteed in case we have nested templates (since we use BFS to process templates) and some tags are represented using same placeholders. This change performs postprocessing more accurate by keeping track of currently active template and searching for matching placeholder.
PR Close#28209
Matias Niemelä
Ben Lesh
Kara Erickson
Andrew Kushnir
Paul Gschwendtner
janith
Pete Bacon Darwin
JoostK
Alan
Kristiyan Kostadinov
Alex Rickabaugh
Olivier Combe
Marc Laval
Greg Magolan
Alex Eagle
Igor Minar
Wassim Chegham
Filipe Silva
George Kalpakas
Alexey Zuev
cexbrayat