Commit Graph

876 Commits

Author SHA1 Message Date
Miško Hevery 2562a3b1b0 fix(ivy): Add `style="{{exp}}"` based interpolation (#34202)
Fixes #33575

Add support for interpolation in styles as shown:
```
<div style="color: {{exp1}}; width: {{exp2}};">
```

PR Close #34202
2020-02-20 15:13:10 -08:00
ayazhafiz a92d97cda7 fix(compiler): report errors for missing binding names (#34595)
Currently, would-be binding attributes that are missing binding names
are not parsed as bindings, and fall through as regular attributes. In
some cases, this can lead to a runtime error; trying to assign `#` as a
DOM attribute in an element like in `<div #></div>` fails because `#` is
not a valid attribute name.

Attributes composed of binding prefixes but not defining a binding
should be considered invalid, as this almost certainly indicates an
unintentional elision of a binding by the developer. This commit
introduces error reporting for attributes with a binding name prefix but
no actual binding name.

Closes https://github.com/angular/vscode-ng-language-service/issues/293.

PR Close #34595
2020-02-10 16:29:32 -08:00
Sonu Kapoor 7fb66eca25 docs: changes AoT to AOT for consistency (#35112)
PR Close #35112
2020-02-04 10:43:33 -08:00
Kristiyan Kostadinov 304584c291 perf(ivy): remove unused argument in hostBindings function (#34969)
We had some logic for generating and passing in the `elIndex` parameter into the `hostBindings` function, but it wasn't actually being used for anything. The only place left that had a reference to it was the `StylingBuilder` and it only stored it without referencing it again.

PR Close #34969
2020-01-27 12:49:35 -08:00
Miško Hevery 9bd9590767 refactor(ivy): change styling to use programmatic API on updates (#34804)
Previously we would write to class/style as strings `element.className` and `element.style.cssText`. Turns out that approach is good for initial render but not good for updates. Updates using this approach are problematic because we have to check to see if there was an out of bound write to style and than perform reconciliation. This also requires the browser to bring up CSS parser which is expensive.

Another problem with old approach is that we had to queue the DOM writes and flush them twice. Once on element advance instruction and once in `hostBindings`. The double flushing is expensive but it also means that a directive can observe that styles are not yet written (they are written after directive executes.)

The new approach uses `element.classList.add/remove` and `element.style.setProperty/removeProperty` API for updates only (it continues to use `element.className` and `element.style.cssText` for initial render as it is cheaper.) The other change is that the styling changes are applied immediately (no queueing). This means that it is the instruction which computes priority. In some circumstances it may result in intermediate writes which are than overwritten with new value. (This should be rare)

Overall this change deletes most of the previous code and replaces it with new simplified implement. The simplification results in code savings.

PR Close #34804
2020-01-24 12:23:19 -08:00
Miško Hevery 5aabe93abe refactor(ivy): Switch styling to new reconcile algorithm (#34616)
NOTE: This change must be reverted with previous deletes so that it code remains in build-able state.

This change deletes old styling code and replaces it with a simplified styling algorithm.

The mental model for the new algorithm is:
- Create a linked list of styling bindings in the order of priority. All styling bindings ere executed in compiled order and than a linked list of bindings is created in priority order.
- Flush the style bindings at the end of `advance()` instruction. This implies that there are two flush events. One at the end of template `advance` instruction in the template. Second one at the end of `hostBindings` `advance` instruction when processing host bindings (if any).
- Each binding instructions effectively updates the string to represent the string at that location. Because most of the bindings are additive, this is a cheap strategy in most cases. In rare cases the strategy requires removing tokens from the styling up to this point. (We expect that to be rare case)S Because, the bindings are presorted in the order of priority, it is safe to resume the processing of the concatenated string from the last change binding.

PR Close #34616
2020-01-24 12:23:00 -08:00
Matias Niemelä 4005815114 refactor(ivy): generate 2 slots per styling instruction (#34616)
Compiler keeps track of number of slots (`vars`) which are needed for binding instructions. Normally each binding instructions allocates a single slot in the `LView` but styling instructions need to allocate two slots.

PR Close #34616
2020-01-24 12:22:44 -08:00
Miško Hevery 2961bf06c6 refactor(ivy): move `hostVars`/`hostAttrs` from instruction to `DirectiveDef` (#34683)
This change moves information from instructions to declarative position:
- `ɵɵallocHostVars(vars)` => `DirectiveDef.hostVars`
- `ɵɵelementHostAttrs(attrs)` => `DirectiveDef.hostAttrs`

When merging directives it is necessary to know about `hostVars` and `hostAttrs`. Before this change the information was stored in the `hostBindings` function. This was problematic, because in order to get to the information the `hostBindings` would have to be executed. In order for `hostBindings` to be executed the directives would have to be instantiated. This means that the directive instantiation would happen before we had knowledge about the `hostAttrs` and as a result the directive could observe in the constructor that not all of the `hostAttrs` have been applied. This further complicates the runtime as we have to apply `hostAttrs` in parts over many invocations.

`ɵɵallocHostVars` was unnecessarily complicated because it would have to update the `LView` (and Blueprint) while existing directives are already executing. By moving it out of `hostBindings` function we can access it statically and we can create correct `LView` (and Blueprint) in a single pass.

This change only changes how the instructions are generated, but does not change the runtime much. (We cheat by emulating the old behavior by calling `ɵɵallocHostVars` and `ɵɵelementHostAttrs`) Subsequent change will refactor the runtime to take advantage of the static information.

PR Close #34683
2020-01-24 12:22:10 -08:00
Misko Hevery 76698d38f7 refactor(ivy): Add style reconciliation algorithm (#34004)
This change introduces class/style reconciliation algorithm for DOM elements.
NOTE: The code is not yet hooked up, it will be used by future style algorithm.

Background:
Styling algorithm currently has [two paths](https://hackmd.io/@5zDGNGArSxiHhgvxRGrg-g/rycZk3N5S)
when computing how the style should be rendered.
1. A direct path which concatenates styling and uses `elemnent.className`/`element.style.cssText` and
2. A merge path which uses internal data structures and uses `element.classList.add/remove`/`element.style[property]`.

The situation is confusing and hard to follow/maintain. So a future PR will remove the merge-path and do everything with
direct-path. This however breaks when some other code adds class or style to the element without Angular's knowledge.
If this happens instead of switching from direct-path to merge-path algorithm, this change provides a different mental model
whereby we always do `direct-path` but the code which writes to the DOM detects the situation and reconciles the out of bound write.

The reconciliation process is as follows:
1. Detect that no one has modified `className`/`cssText` and if so just write directly (fast path).
2. If out of bounds write did occur, switch from writing using `className`/`cssText` to `element.classList.add/remove`/`element.style[property]`.
   This does require that the write function computes the difference between the previous Angular expected state and current Angular state.
   (This requires a parser. The advantage of having a parser is that we can support `style="width: {{exp}}px" kind of bindings.`)
   Compute the diff and apply it in non destructive way using `element.classList.add/remove`/`element.style[property]`

Properties of approach:
- If no out of bounds style modification:
  - Very fast code path: Just concatenate string in right order and write them to DOM.
  - Class list order is preserved
- If out of bounds style modification detected:
  - Penalty for parsing
  - Switch to non destructive modification: `element.classList.add/remove`/`element.style[property]`
  - Switch to alphabetical way of setting classes.

PR Close #34004
2020-01-24 12:21:39 -08:00
Paul Gschwendtner 970b22f98e test: setup circular dependency tests for all entry points (#34774)
Sets up circular dependency tests for all entry-points in the
project (except for the ones part of a deprecated package).

PR Close #34774
2020-01-23 11:36:40 -08:00
Matias Niemelä 32489c7426 revert: refactor(ivy): remove styleSanitizer instruction in favor of an inline param (#34480) (#34910)
This reverts commit 84d24c08e1.

PR Close #34910
2020-01-22 15:59:33 -05:00
Matias Niemelä 84d24c08e1 refactor(ivy): remove styleSanitizer instruction in favor of an inline param (#34480)
This patch removes the need for the styleSanitizer() instruction in
favor of passing the sanitizer into directly into the styleProp
instruction.

This patch also increases the binding index size for all style/class bindings in preparation for #34418

PR Close #34480
2020-01-22 14:35:00 -05:00
Andrew Kushnir 39ec188003 fix(ivy): more accurate detection of pipes in host bindings (#34655)
Pipes in host binding expressions are not supported in View Engine and Ivy, but in some more complex cases (like `(value | pipe) === true`) compiler was not reporting errors. This commit extends Ivy logic to detect pipes in host binding expressions and throw in cases bindings are present. View Engine behavior remains the same.

PR Close #34655
2020-01-21 13:22:00 -05:00
Igor Minar 63c9c2d2be fix: work around 'noImplicityAny' incompatibility due to ts3.7 update (#34798)
Typescript 3.7 now emits d.ts files for getters differently than prior versions,
and there seems to be a bug in how it strips private types without replacing them
with explicit 'any' type. This then leads to compilation failures in projects compiled
against our packages that don't have skipLibCheck turned on but do have strict or
noImplicitAny check on.

I'm working around this by marking the affected getters as @internal and
adding a test to prevent future regressions.

I believe this is a TypeScript bug, and I filed a bug report:
https://github.com/microsoft/TypeScript/issues/36216

PR Close #34798
2020-01-16 12:06:57 -05:00
Greg Magolan a28c02bf89 build: derive ts_library dep from jasmine_node_test boostrap label if it ends in `_es5` (#34736)
PR Close #34736
2020-01-15 14:58:07 -05:00
Greg Magolan aee67f08d9 test: handle bootstrap templated_args in jasmine_node_test defaults.bzl (#34736)
PR Close #34736
2020-01-15 14:58:07 -05:00
Greg Magolan dcff76e8b9 refactor: handle breaking changes in rules_nodejs 1.0.0 (#34736)
The major one that affects the angular repo is the removal of the bootstrap attribute in nodejs_binary, nodejs_test and jasmine_node_test in favor of using templated_args --node_options=--require=/path/to/script. The side-effect of this is that the bootstrap script does not get the require.resolve patches with explicitly loading the targets _loader.js file.

PR Close #34736
2020-01-15 14:58:07 -05:00
atscott 538d0446b5 Revert "refactor: handle breaking changes in rules_nodejs 1.0.0 (#34589)" (#34730)
This reverts commit 9bb349e1c8.

PR Close #34730
2020-01-10 14:12:15 -08:00
atscott 5e60215470 Revert "test: handle bootstrap templated_args in jasmine_node_test defaults.bzl (#34589)" (#34730)
This reverts commit da4782e67f.

PR Close #34730
2020-01-10 14:12:15 -08:00
atscott 24679d8676 Revert "build: derive ts_library dep from jasmine_node_test boostrap label if it ends in `_es5` (#34589)" (#34730)
This reverts commit 79a0d007b4.

PR Close #34730
2020-01-10 14:12:14 -08:00
Greg Magolan 79a0d007b4 build: derive ts_library dep from jasmine_node_test boostrap label if it ends in `_es5` (#34589)
PR Close #34589
2020-01-10 08:32:00 -08:00
Greg Magolan da4782e67f test: handle bootstrap templated_args in jasmine_node_test defaults.bzl (#34589)
PR Close #34589
2020-01-10 08:31:59 -08:00
Greg Magolan 9bb349e1c8 refactor: handle breaking changes in rules_nodejs 1.0.0 (#34589)
The major one that affects the angular repo is the removal of the bootstrap attribute in nodejs_binary, nodejs_test and jasmine_node_test in favor of using templated_args --node_options=--require=/path/to/script. The side-effect of this is that the bootstrap script does not get the require.resolve patches with explicitly loading the targets _loader.js file.

PR Close #34589
2020-01-10 08:31:59 -08:00
Andrew Scott 4d7a9db44c fix(ivy): Ensure ngProjectAs marker name appears at even attribute index (#34617)
The `getProjectAsAttrValue` in `node_selector_matcher` finds the
ProjectAs marker and then additionally checks that the marker appears in
an even index of the node attributes because "attribute names are stored
at even indexes". This is true for "regular" attribute bindings but
classes, styles, bindings, templates, and i18n do not necessarily follow
this rule because there can be an uneven number of them, causing the
next "special" attribute "name" to appear at an odd index. To address
this issue, ensure ngProjectAs is placed right after "regular"
attributes.

PR Close #34617
2020-01-07 10:51:46 -08:00
Andrew Kushnir b4c5bdb093 fix(ivy): append `advance` instructions before `i18nExp` (#34436)
Prior to this commit, there were no `advance` instructions generated before `i18nExp` instructions and as a result, lifecycle hooks for components used inside i18n blocks were flushed too late. This commit adds the logic to generate `advance` instructions in front of `i18nExp` ones (similar to what we have in other places like interpolations, property bindings, etc), so that the necessary lifecycle hooks are flushed before expression value is captured.

PR Close #34436
2020-01-07 10:31:45 -08:00
ayazhafiz 19944c2424 feat(compiler): record end of expression Token (#33549)
In the past, only the starting index of an expression Token has been
recorded, so a parser could demarkate the span of a token only by the
start locations of two tokens. This may lead to trailing whitespace
being included in the token span:

```html
{{ token1   + token2 }}
   ^^^^^^^^^             recorded span of `token1`
```

It's also not enough for a parser to determine the end of a token by
adding the length of the token value to the token's start location,
because lexed expression values may not exactly reflect the source code.
For example, `"d\\"e"` is lexed as a string token whose value is `d"e`.

Instead, this commit adds a `end` field to expression tokens. `end`
is one past the last index of the token source code. This will enable a
parser to determine the span of a token just by looking at that token.

This is a breaking change because the contructor interface of `Token`
has changed.

Part of #33477.

PR Close #33549
2020-01-06 11:00:15 -08:00
JoostK 8c6468a025 refactor(ivy): use absolute source spans in type checker (#34417)
Previously, the type checker would compute an absolute source span by
combining an expression AST node's `ParseSpan` (relative to the start of
the expression) together with the absolute offset of the expression as
represented in a `ParseSourceSpan`, to arrive at a span relative to the
start of the file. This information is now directly available on an
expression AST node in the `AST.sourceSpan` property, which can be used
instead.

PR Close #34417
2019-12-18 14:44:42 -08:00
Pete Bacon Darwin 31be29a9f3 fix(ngcc): use the correct identifiers when updating typings files (#34254)
Previously the identifiers used in the typings files were the same as
those used in the source files.

When the typings files and the source files do not match exactly, e.g.
when one of them is flattened, while the other is a deep tree, it is
possible for identifiers to be renamed.

This commit ensures that the correct identifier is used in typings files
when the typings file does not export the same name as the source file.

Fixes https://github.com/angular/ngcc-validation/pull/608

PR Close #34254
2019-12-18 11:25:01 -08:00
Ayaz Hafiz 3e201181bb fix(ivy): correctly associate output bound events with directives (#31938)
Previously, bound events were incorrectly bound to directives with
inputs matching the bound event attribute. This fixes that so bound
events can only be bound to directives with matching outputs.

Adds tests for all kinds of directive matching on bound attributes.

PR Close #31938
2019-12-17 14:39:33 -08:00
Ayaz Hafiz ddc229b69b fix(ivy): record correct absolute source span for ngForOf expressions (#31813)
Expressions in an inline template binding are improperly recorded as
spaning an offset calculated from the start of the template binding
attribute key, whereas they should be calculated from the start of the
attribute value, which contains the actual binding AST.

PR Close #31813
2019-12-16 08:11:48 -08:00
JoostK ff0a91422a perf(compiler): speed up i18n digest computations (#34332)
Avoids the usage of array destructuring, as it introduces calls to
a `__values` helper function in ES5 that has a relatively high
performance impact. This shaves off roughly 130ms of CPU time for a
large compilation with big templates that uses i18n.

PR Close #34332
2019-12-12 14:06:37 -08:00
JoostK 014a7137f4 perf(compiler): use a shared interpolation regex (#34332)
The template parser has a certain interpolation config associated with
it and builds a regular expression each time it needs to extract the
interpolations from an input string. Since the interpolation config is
typically the default of `{{` and `}}`, the regular expression doesn't
have to be recreated each time. Therefore, this commit creates only a
single regular expression instance that is used for the default
configuration.

In a large compilation unit with big templates, computing the regular
expression took circa 275ms. This change reduces this to effectively
zero.

PR Close #34332
2019-12-12 14:06:37 -08:00
JoostK 4945274080 perf(compiler): optimize cloning cursors state (#34332)
On a large compilation unit with big templates, the total time spent in
the `PlainCharacterCursor` constructor was 470ms. This commit applies
two optimizations to reduce this time:

1. Avoid the object spread operator within the constructor, as the
generated `__assign` helper in the emitted UMD bundle (ES5) does not
optimize well compared to a hardcoded object literal. This results in a
significant performance improvement. Because of the straight-forward
object literal, the VM is now much better able to optimize the memory
allocations which makes a significant difference as the
`PlainCharacterCursor` constructor is called in tight loops.

2. Reduce the number of `CharacterCursor` clones. Although cloning
itself is now much faster because of the optimization above, several
clone operations were not necessary.

Combined, these changes reduce the total time spent in the
`PlainCharacterCursor` constructor to just 10ms.

PR Close #34332
2019-12-12 14:06:37 -08:00
JoostK 6e5f076330 perf(ivy): share instances of `DomElementSchemaRegistry` (#34332)
To create a binding parser, an instance of `ElementSchemaRegistry` is
required. Prior to this change, each time a new binding parser was
created a new instance of `DomElementSchemaRegistry` would be
instantiated. This is an expensive operation that takes roughly 1ms per
instantiation, so it is key that multiple allocations are avoided.

By sharing a single `DomElementSchemaRegistry`, we avoid two such
allocations, i.e. save ~2ms, per component template.

PR Close #34332
2019-12-12 14:06:36 -08:00
JoostK b72c7a89a9 refactor(ivy): include generic type for `ModuleWithProviders` in .d.ts files (#34235)
The `ModuleWithProviders` type has an optional type parameter that
should be specified to indicate what NgModule class will be provided.
This enables the Ivy compiler to statically determine the NgModule type
from the declaration files. This type parameter will become required in
the future, however to aid in the migration the compiler will detect
code patterns where using `ModuleWithProviders` as return type is
appropriate, in which case it transforms the emitted .d.ts files to
include the generic type argument.

This should reduce the number of occurrences where `ModuleWithProviders`
is referenced without its generic type argument.

Resolves FW-389

PR Close #34235
2019-12-10 16:34:47 -08:00
Alex Rickabaugh 13c2fad240 fix(ivy): throw a better error when DI can't inject a ctor param (#33739)
Occasionally a factory function needs to be generated for an "invalid"
constructor (one with parameters types which aren't injectable). Typically
this happens in JIT mode where understanding of parameters cannot be done in
the same "up-front" way that the AOT compiler can.

This commit changes the JIT compiler to generate a new `invalidFactoryDep`
call for each invalid parameter. This instruction will error at runtime if
called, indicating both the index of the invalid parameter as well as (via
the stack trace) the factory function which was generated for the type being
constructed.

Fixes #33637

PR Close #33739
2019-12-09 11:37:10 -08:00
Pete Bacon Darwin a12b5f930a fix(compiler): ensure localized strings are ES5 compatible for JIT mode (#34265)
Previously the JIT evaluated code for ivy localized strings included
backtick tagged template strings, which are not compatible with ES5
in legacy browsers such as IE 11.

Now the generated code is ES5 compatible.

Fixes #34246

PR Close #34265
2019-12-06 13:03:46 -08:00
Pete Bacon Darwin c4ce24647b fix(compiler-cli): ensure that `ngI18nClosureMode` is guarded in generated code (#34211)
If the `ngI18nClosureMode` global check actually makes it
through to the runtime, then checks for its existence should
be guarded to prevent `Reference undefined` errors in strict
mode.

(Normally, it is stripped out by dead code elimination during
build optimization.)

This comment ensures that generated template code guards
this global check.

PR Close #34211
2019-12-03 16:18:12 -08:00
Andrew Kushnir c50faa97ca fix(ivy): correctly support `ngProjectAs` on templates (#34200)
Prior to this commit, if a template (for example, generated using structural directive such as *ngIf) contains `ngProjectAs` attribute, it was not included into attributes array in generated code and as a result, these templates were not matched at runtime during content projection. This commit adds the logic to append `ngProjectAs` values into corresponding element's attribute arrays, so content projection works as expected.

PR Close #34200
2019-12-03 16:12:55 -08:00
arturovt 627814cc4a docs(compiler): fix typos and spelling (#34008)
PR Close #34008
2019-12-03 16:05:32 -08:00
Pete Bacon Darwin 6b1a47183d fix(ivy): i18n - trim whitespace when parsing metadata (#34154)
It is possible for HTML formatters to add whitespace
around the content of `i18n` attribute values. This can
make the meaning and custom ids brittle to simple
whitespace formatting.

This commit ensures that the metadata string extracted
from HTML `i18n` attributes is trimmed before being parsed
into meaning, description and custom id.

PR Close #34154
2019-12-03 10:20:53 -08:00
Pete Bacon Darwin 41485599f3 refactor(compiler): remove redundant `metaFromI18nMessage()` function (#34154)
PR Close #34154
2019-12-03 10:20:49 -08:00
Pete Bacon Darwin f6a6f26e0f fix(compiler): i18n - trim whitespace from i18n custom ids (#34154)
Fixes #34147

PR Close #34154
2019-12-03 10:16:56 -08:00
Pete Bacon Darwin e524322c43 refactor(compiler): i18n - render legacy i18n message ids (#34135)
Now that `@angular/localize` can interpret multiple legacy message ids in the
metablock of a `$localize` tagged template string, this commit adds those
ids to each i18n message extracted from component templates, but only if
the `enableI18nLegacyMessageIdFormat` is not `false`.

PR Close #34135
2019-12-03 10:15:53 -08:00
Kara Erickson 67eac733d2 refactor(ivy): do not generate providedIn: null (#34116)
We should only generate the `providedIn` property in injectable
defs if it has a non-null value. `null` does not communicate
any information to the runtime that isn't communicated already
by the absence of the property.

This should give us some modest code size savings.

PR Close #34116
2019-12-03 10:14:52 -08:00
Kara Erickson 755d2d572f refactor(ivy): remove unnecessary fac wrapper (#34076)
For injectables, we currently generate a factory function in the
injectable def (prov) that delegates to the factory function in
the factory def (fac). It looks something like this:

```
factory: function(t) { return Svc.fac(t); }
```

The extra wrapper function is unnecessary since the args for
the factory functions are the same. This commit changes the
compiler to generate this instead:

```
factory: Svc.fac
```

Because we are generating less code for each injectable, we
should see some modest code size savings. AIO's main bundle
is about 1 KB smaller.

PR Close #34076
2019-12-02 11:35:24 -08:00
Andrew Kushnir 5de7960f01 fix(ivy): take styles extracted from template into account in JIT mode (#34017)
Prior to this commit, all styles extracted from Component's template (defined using <style> tags) were ignored by JIT compiler, so only `styles` array values defined in @Component decorator were used. This change updates JIT compiler to take styles extracted from the template into account. It also ensures correct order where `styles` array values are applied first and template styles are applied second.

PR Close #34017
2019-11-25 22:38:42 -05:00
arturovt 9ba5344f3e docs: fix typos in compiler API comments (#33977)
PR Close #33977
2019-11-25 18:38:47 -05:00
Alex Rickabaugh 08a4f10ee7 fix(ivy): move setClassMetadata calls into a pure iife (#33337)
This commit transforms the setClassMetadata calls generated by ngtsc from:

```typescript
/*@__PURE__*/ setClassMetadata(...);
```

to:

```typescript
/*@__PURE__*/ (function() {
  setClassMetadata(...);
})();
```

Without the IIFE, terser won't remove these function calls because the
function calls have arguments that themselves are function calls or other
impure expressions. In order to make the whole block be DCE-ed by terser,
we wrap it into IIFE and mark the IIFE as pure.

It should be noted that this change doesn't have any impact on CLI* with
build-optimizer, which removes the whole setClassMetadata block within
the webpack loader, so terser or webpack itself don't get to see it at
all. This is done to prevent cross-chunk retention issues caused by
webpack's internal module registry.

* actually we do expect a short-term size regression while
https://github.com/angular/angular-cli/pull/16228
is merged and released in the next rc of the CLI. But long term this
change does nothing to CLI + build-optimizer configuration and is done
primarly to correct the seemingly correct but non-function PURE annotation
that builds not using build-optimizer could rely on.

PR Close #33337
2019-11-20 12:55:58 -08:00
Alex Rickabaugh b54ed980ed fix(ivy): retain JIT metadata unless JIT mode is explicitly disabled (#33671)
NgModules in Ivy have a definition which contains various different bits
of metadata about the module. In particular, this metadata falls into two
categories:

* metadata required to use the module at runtime (for bootstrapping, etc)
in AOT-only applications.
* metadata required to depend on the module from a JIT-compiled app.

The latter metadata consists of the module's declarations, imports, and
exports. To support JIT usage, this metadata must be included in the
generated code, especially if that code is shipped to NPM. However, because
this metadata preserves the entire NgModule graph (references to all
directives and components in the app), it needs to be removed during
optimization for AOT-only builds.

Previously, this was done with a clever design:

1. The extra metadata was added by a function called `setNgModuleScope`.
A call to this function was generated after each NgModule.
2. This function call was marked as "pure" with a comment and used
`noSideEffects` internally, which causes optimizers to remove it.

The effect was that in dev mode or test mode (which use JIT), no optimizer
runs and the full NgModule metadata was available at runtime. But in
production (presumably AOT) builds, the optimizer runs and removes the JIT-
specific metadata.

However, there are cases where apps that want to use JIT in production, and
still make an optimized build. In this case, the JIT-specific metadata would
be erroneously removed. This commit solves that problem by adding an
`ngJitMode` global variable which guards all `setNgModuleScope` calls. An
optimizer can be configured to statically define this global to be `false`
for AOT-only builds, causing the extra metadata to be stripped.

A configuration for Terser used by the CLI is provided in `tooling.ts` which
sets `ngJitMode` to `false` when building AOT apps.

PR Close #33671
2019-11-20 12:55:43 -08:00