☂️ Symbol/Scope Resolution

[xunilrj]

This issue is tracking all the implementation to achieve two tasks:

1 - Allow "go to definition" on the editor;
2 - Allow to warn against "unused Variables" when linting;

See this discussion about the semantic model architecture: #2614
See this discussion about the architecture on how the semantic model is going to be used inside linters: #2603

Steps

This is my suggestion for implementing the two tasks above. It is actually a progressive implementation:

1 - We do not offer a semantic façade at all. "unusedVariables" lint would just consume the parsing tree, and iterate it to find unused variables;
2 - We cache this iteration somehow to make the lint have a decent performance;
3 - We build the "service/context" architecture that will be passed into the lint;
4 - We store the "service/context" inside NodeData;
5 - We create the untyped Semantic Tree;
6 - We change the "unusedVariable" lint rule to use the semantic tree.
7 - We implement the typed Semantic Tree. Probably just the first SemanticJsVariableDeclaration.
8 - We change the "unusedVariable" lint rule to query for the type semantic tree.

Tasks

• Parse Microsoft/ts .symbols file (see feature(rome_js_parser): coverage test suite for ts symbols file #2588)
  • basic coverage test running
  • achieve +90% of passess
• Generate Symbols Events
  • DeclarationFound
  • ReferenceFound
• Implement simple Scope resolution
  • ScopeStarted
  • ScopeEnded
• Support Hoisting
  • ReferenceSolved
• LSP
  • F12 - go to definition
• Lint
  • lint for "unused variable"

[ematipico]

Will this be part of the parsing phase or another another phase after the parsing phase?

[xunilrj]

Another pass.
The final architecture, we are still discussing (#2603)

So for these tasks, it will actually be another function that will be called manually when testing.

[xunilrj]

To reach 90% we need to deal with a lot of edge cases that are not relevant for the moment.

[xunilrj]

"Goto definition" will only be relevant when we run and the only LSP (non vscode).