ngtsc has an internal performance tracing package, which previously has not really seen much use. It used to track performance statistics on a very granular basis (microseconds per actual class analysis, for example). This had two problems: * it produced voluminous amounts of data, complicating the analysis of such results and providing dubious value. * it added nontrivial overhead to compilation when used (which also affected the very performance of the operations being measured). This commit replaces the old system with a streamlined performance tracing setup which is lightweight and designed to be always-on. The new system tracks 3 metrics: * time taken by various phases and operations within the compiler * events (counters) which measure the shape and size of the compilation * memory usage measured at various points of the compilation process If the compiler option `tracePerformance` is set, the compiler will serialize these metrics to a JSON file at that location after compilation is complete. PR Close #41125
Angular Compatibility Compiler (ngcc)
This compiler will convert node_modules compiled with ngc, into node_modules which
appear to have been compiled with ngtsc.
This conversion will allow such "legacy" packages to be used by the Ivy rendering engine.
Building
The project is built using Bazel:
yarn bazel build //packages/compiler-cli/ngcc
Unit Testing
The unit tests are built and run using Bazel:
yarn bazel test //packages/compiler-cli/ngcc/test
Integration Testing
There are tests that check the behavior of the overall executable:
yarn bazel test //packages/compiler-cli/ngcc/test:integration