This commit changes module loading implementation in "deno_core"
to call "ModuleLoader::prepare" hook only once per entry point.
This is done to avoid multiple type checking of the same code
in case of duplicated dynamic imports.
Relevant code in "cli/module_graph.rs" was updated as well.
This commit adds incremental compilation capabilities to internal TS compiler.
Instead of using "ts.createProgram()" API for compilation step (during deno
startup), "ts.createIncrementalProgram()" API is used instead.
Thanks to TS' ".tsbuildinfo" file that already stores all necessary metadata
for compilation I was able to remove our own invention that is ".graph" file.
".tsbuildinfo" file is stored alongside compiled source and is used to
cache-bust outdated dependencies, facilitated by the "version" field.
The value for "version" field is computed in Rust during loading of module
graph and is basically a hash of the file contents.
Please keep in mind that incremental compilation is only used for initial
compilation (or dynamic imports compilation) - bundling and runtime compiler
APIs haven't been changed at all.
Due to problems with source map I changed compilation settings to inline
source map (inlineSourceMap instead of sourceMap).
This commit fixes several regressions in TS compiler:
* double compilation of same module during same process run
* compilation of JavaScript entry point with non-JS imports
* unexpected skip of emit during compilation
Additional checks were added to ensure "allowJs" setting is
used in TS compiler if JavaScript has non-JS dependencies.
