fixes signature help resolution for callexpressions

[georgejecook]

This pr addresses the following issues:

• Cannot bring up signature help for nested call expressions
• Cannot bring up signature help for multi-lined functions
• Cannot bring up signature help for function calls with parenthesis in the arguments.

This implementation uses the new AST searchign, and parent offerings; plus some of the work done to imrpove AST fail-over when a parsing failure occurs (e.g. for presently-edited-lines, which may have invalid parenthesis/bracket pairing).

I took the approach of consolidating code that was in Program and in BrsFile, into SignatureHlepInfo, which is conceptually part of the bscPlugin.

I also added the CallExpressionInfo class, to allow us to process and store info about a call expressions' state and type, which is useful for signature resolution, and, in my next few contributions, improvements to completions, and go to definition, too.

Testing is exhaustive, having covered the types:

• call expression
• call func expression
• namespaced call expression
• class method call expression
• class method on my own class (i.e. my m)
• constructor call expression
• mutliline
• commas
• white spaces
• undefined/error scenarios.

However, due to having written this on program originally, then extracting to the utility classes, the tests are more integration tests in their nature.

I have also shared video of how the feature works in the IDE, which clearly demonstrates the great improvements herein.

[georgejecook]

Added @triwav because I know he worked on some of this before :)

[georgejecook]

note - 2 tests are failing due to sourcemap errors. reached out to @TwitchBronBron about that.

     Error: You must provide the URL of lib/mappings.wasm by calling SourceMapConsumer.initialize({ 'lib/mappings.wasm': ... }) before using SourceMapConsumer
      at readWasm (/home/georgejecook/hope/open-source/vsc/brighterscript/node_modules/source-map/lib/read-wasm.js:8:13)
      at wasm (/home/georgejecook/hope/open-source/vsc/brighterscript/node_modules/source-map/lib/wasm.js:25:16)
      at /home/georgejecook/hope/open-source/vsc/brighterscript/node_modules/source-map/lib/source-map-consumer.js:264:14
      at processTicksAndRejections (node:internal/process/task_queues:95:5)
      at Context.<anonymous> (/home/georgejecook/hope/open-source/vsc/brighterscript/src/files/BrsFile.spec.ts:2507:28)

[triwav]

Only gave it a quick review but looks good from what I could see. Thanks @georgejecook

[TwitchBronBron]

Overall, this looks pretty good! I went ahead and refactored the unit tests to use proper indentation and eliminate the beforeEach usage in favor of dedicated code block for each test.

Just one primary thing to address and one question and then I think this should be good to go.

[georgejecook]

Overall, this looks pretty good! I went ahead and refactored the unit tests to use proper indentation and eliminate the beforeEach usage in favor of dedicated code block for each test.

That was jolly decent of you - I really appreciate your help there. T h a n k s