Description

Fixes#18553.
Breaking change.

This PR is non-breaking for two of the three #line use cases mentioned in#18553.
It keeps the original ranges in the AST, stores the #line directives in a table and provides a methodrange.ApplyLineDirectives(). This method is applied in the following places

• construction of runtime diagnostics in pattern match compilation
• emitting debug information in quotation translation
• creating IL source markers (debug information)
• formatting fsc compiler diagnostics (CompilerDiagnostics.FormatDiagnosticLocation)
• creating service diagnostics (FSharpDiagnostics.CreateFromException)

This should make sure that all debugging information (in .pdb) and all diagnostics stay unchanged.

The third use case, symbol positions for IDE editors, is more tricky.FSharpSymbol has no range field or property that I could apply the transformation to, but just contains (and makes public) the AST items with their original ranges.
So, I propose we leave it like this and callApplyLineDirectives in the appropriate places in FSAC / the editors.
This will also enable better line directive support in the editors (for some use cases you need the original ranges).
For Ionide / FSAC I found that callingApplyLineDirectives in a single place (in FSAC'sfcsRangeToLspLocation) will most probably be sufficient to support the current functionality.
I don't know what it means for the other editors.
Any thoughts or recommendations here? (@TheAngryByrd@auduchinok@abonie )

List of breaking changes

• For fsc and fcs users
  • __LINE__ and__SOURCE_FILE__ show original locations now
• For fcs users only (tooling)
  • AST has original ranges now (ignoring #line directives) (so, alsoFSharpSymbol points to its original range)

Checklist

• Test cases added
• Performance benchmarks added in case of performance changes
• Release notes entry updated