In #33551, a bug in `ngc --watch` mode was fixed so that a component is
recompiled when its template file is changed. Due to insufficient
normalization of files paths, this fix did not have the desired effect
on Windows.
Fixes#32869
PR Close#34015
This commit fixes a bug in the incremental rebuild engine of ngtsc, where if
a component was removed from its NgModule, it would not be properly
re-emitted.
The bug stemmed from the fact that whether to emit a file was a decision
based purely on the updated dependency graph, which captures the dependency
structure of the rebuild program. This graph has no edge from the component
to its former module (as it was removed, of course), so the compiler
erroneously decides not to emit the component.
The bug here is that the compiler does know, from the previous dependency
graph, that the component file has logically changed, since its previous
dependency (the module file) has changed. This information was not carried
forward into the set of files which need to be emitted, because it was
assumed that the updated dependency graph was a more accurate source of that
information.
With this commit, the set of files which need emit is pre-populated with the
set of logically changed files, to cover edge cases like this.
Fixes#34813
PR Close#34912
Currently the decorator handlers are run against all `SourceFile`s in the compilation, but we shouldn't be doing it against declaration files. This initially came up as a CI issue in #33264 where it was worked around only for the `DirectiveDecoratorHandler`. These changes move the logic into the `TraitCompiler` and `DecorationAnalyzer` so that it applies to all of the handlers.
PR Close#34557
Previously, the compiler performed an incremental build by analyzing and
resolving all classes in the program (even unchanged ones) and then using
the dependency graph information to determine which .js files were stale and
needed to be re-emitted. This algorithm produced "correct" rebuilds, but the
cost of re-analyzing the entire program turned out to be higher than
anticipated, especially for component-heavy compilations.
To achieve performant rebuilds, it is necessary to reuse previous analysis
results if possible. Doing this safely requires knowing when prior work is
viable and when it is stale and needs to be re-done.
The new algorithm implemented by this commit is such:
1) Each incremental build starts with knowledge of the last known good
dependency graph and analysis results from the last successful build,
plus of course information about the set of files changed.
2) The previous dependency graph's information is used to determine the
set of source files which have "logically" changed. A source file is
considered logically changed if it or any of its dependencies have
physically changed (on disk) since the last successful compilation. Any
logically unchanged dependencies have their dependency information copied
over to the new dependency graph.
3) During the `TraitCompiler`'s loop to consider all source files in the
program, if a source file is logically unchanged then its previous
analyses are "adopted" (and their 'register' steps are run). If the file
is logically changed, then it is re-analyzed as usual.
4) Then, incremental build proceeds as before, with the new dependency graph
being used to determine the set of files which require re-emitting.
This analysis reuse avoids template parsing operations in many circumstances
and significantly reduces the time it takes ngtsc to rebuild a large
application.
Future work will increase performance even more, by tackling a variety of
other opportunities to reuse or avoid work.
PR Close#34288
Previously, our incremental build system kept track of the changes between
the current compilation and the previous one, and used its knowledge of
inter-file dependencies to evaluate the impact of each change and emit the
right set of output files.
However, a problem arose if the compiler was not able to extract a
dependency graph successfully. This typically happens if the input program
contains errors. In this case the Angular analysis part of compilation is
never executed.
If a file changed in one of these failed builds, in the next build it
appears unchanged. This means that the compiler "forgets" to emit it!
To fix this problem, the compiler needs to know the set of changes made
_since the last successful build_, not simply since the last invocation.
This commit changes the incremental state system to much more explicitly
pass information from the previous to the next compilation, and in the
process to keep track of changes across multiple failed builds, until the
program can be analyzed successfully and the results of those changes
incorporated into the emit plan.
Fixes#32214
PR Close#33971
Previously, the ngtsc compiler attempted to reuse analysis work from the
previous program during an incremental build. To do this, it had to prove
that the work was safe to reuse - that no changes made to the new program
would invalidate the previous analysis.
The implementation of this had a significant design flaw: if the previous
program had errors, the previous analysis would be missing significant
information, and the dependency graph extracted from it would not be
sufficient to determine which files should be re-analyzed to fill in the
gaps. This often meant that the build output after an error was resolved
would be wholly incorrect.
This commit switches ngtsc to take a simpler approach to incremental
rebuilds. Instead of attempting to reuse prior analysis work, the entire
program is re-analyzed with each compilation. This is actually not as
expensive as one might imagine - analysis is a fairly small part of overall
compilation time.
Based on the dependency graph extracted during this analysis, the compiler
then can make accurate decisions on whether to emit specific files. A new
suite of tests is added to validate behavior in the presence of source code
level errors.
This new approach is dramatically simpler than the previous algorithm, and
should always produce correct results for a semantically correct program.s
Fixes#32388Fixes#32214
PR Close#33862
During incremental compilations, ngtsc needs to know which metadata
from a previous compilation can be reused, versus which metadata has to
be recomputed as some dependency was updated. Changes to
directives/components should cause the NgModule in which they are
declared to be recompiled, as the NgModule's compilation is dependent
on its directives/components.
When a dependent source file of a directive/component is updated,
however, a more subtle dependency should also cause to NgModule's source
file to be invalidated. During the reconciliation of state from a
previous compilation into the new program, the component's source file
is invalidated because one of its dependency has changed, ergo the
NgModule needs to be invalidated as well. Up until now, this implicit
dependency was not imposed on the NgModule. Additionally, any change to
a dependent file may influence the module scope to change, so all
components within the module must be invalidated as well.
This commit fixes the bug by introducing additional file dependencies,
as to ensure a proper rebuild of the module scope and its components.
Fixes#32416
PR Close#33522
Recently it was made possible to have a directive without selector,
which are referred to as abstract directives. Such directives should not
be registered in an NgModule, but can still contain decorators for
inputs, outputs, queries, etc. The information from these decorators and
the `@Directive()` decorator itself needs to be registered with the
central `MetadataRegistry` so that other areas of the compiler can
request information about a given directive, an example of which is the
template type checker that needs to know about the inputs and outputs of
directives.
Prior to this change, however, abstract directives would only register
themselves with the `MetadataRegistry` as being an abstract directive,
without all of its other metadata like inputs and outputs. This meant
that the template type checker was unable to resolve the inputs and
outputs of these abstract directives, therefore failing to check them
correctly. The typical error would be that some property does not exist
on a DOM element, whereas said property should have been bound to the
abstract directive's input.
This commit fixes the problem by always registering the metadata of a
directive or component with the `MetadataRegistry`. Tests have been
added to ensure abstract directives are handled correctly in the
template type checker, together with tests to verify the form of
abstract directives in declaration files.
Fixes#30080
PR Close#33131
Previously if only a component template changed then we would know to
rebuild its component source file. But the compilation was incorrect if the
component was part of an NgModule, since we were not capturing the
compilation scope information that had a been acquired from the NgModule
and was not being regenerated since we were not needing to recompile
the NgModule.
Now we register compilation scope information for each component, via the
`ComponentScopeRegistry` interface, so that it is available for incremental
compilation.
The `ComponentDecoratorHandler` now reads the compilation scope from a
`ComponentScopeReader` interface which is implemented as a compound
reader composed of the original `LocalModuleScopeRegistry` and the
`IncrementalState`.
Fixes#31654
PR Close#31932
Versions of CLI prior to angular/angular-cli@0e339ee did not expose the host.getModifiedResourceFiles() method.
This meant that null was being passed through to the IncrementalState.reconcile() method
to indicate that there were either no changes or the host didn't support that method.
This commit fixes a bug where we were checking for undefined rather than null when
deciding whether any resource files had changed, causing a null reference error to be thrown.
This bug was not caught by the unit testing because the tests set up the changed files
via a slightly different process, not having access to the CompilerHost, and these test
were making the erroneous assumption that undefined indicated that there were no
changed files.
PR Close#31322
Optimizations to skip compiling source files that had not changed
did not account for the case where only a resource file changes,
such as an external template or style file.
Now we track such dependencies and trigger a recompilation
if any of the previously tracked resources have changed.
This will require a change on the CLI side to provide the list of
resource files that changed to trigger the current compilation by
implementing `CompilerHost.getModifiedResourceFiles()`.
Closes#30947
PR Close#30954
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
To support skipping analysis of a file containing a component
we need to know that none of the declarations that might affect
its ngtsc compilation have not changed. The files that we need to
check are those that contain classes from the `CompilationScope`
of the component. These classes are already tracked in the
`LocalModuleScopeRegistry`.
This commit modifies the `IvyCompilation` class to record the
files that are in each declared class's `CompilationScope` via
a new method, `recordNgModuleScopeDependencies()`, that is called
after all the handlers have been "resolved".
Further, if analysis is skipped for a declared class, then we need
to recover the analysis from the previous compilation run. To
support this, the `IncrementalState` class has been updated to
expose the `MetadataReader` and `MetadataRegistry` interfaces.
This is included in the `metaRegistry` object to capture these analyses,
and also in the `localMetaReader` as a fallback to use if the
current compilation analysis was skipped.
PR Close#30238
As part of incremental compilation performance improvements, we need
to track the dependencies of files due to expressions being evaluated by
the `PartialEvaluator`.
The `PartialEvaluator` now accepts a `DependencyTracker` object, which is
used to track which files are visited when evaluating an expression.
The interpreter computes this `originatingFile` and stores it in the evaluation
`Context` so it can pass this to the `DependencyTracker.
The `IncrementalState` object implements this interface, which allows it to be
passed to the `PartialEvaluator` and so capture the file dependencies.
PR Close#30238
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
