jpsim / jpsim/SourceKitten

Is there a way to get implied type information?

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Dominant language
Swift
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Description

For example on the following file:

class Thing {
    let object = 5
}

sourcekitten structure --file produces

{
  "key.substructure" : [
    {
      "key.kind" : "source.lang.swift.decl.class",
      "key.offset" : 0,
      "key.nameoffset" : 6,
      "key.namelength" : 5,
      "key.bodyoffset" : 13,
      "key.bodylength" : 20,
      "key.accessibility" : "source.lang.swift.accessibility.internal",
      "key.substructure" : [
        {
          "key.kind" : "source.lang.swift.decl.var.instance",
          "key.offset" : 18,
          "key.nameoffset" : 22,
          "key.namelength" : 6,
          "key.length" : 14,
          "key.accessibility" : "source.lang.swift.accessibility.internal",
          "key.typename" : "object",
          "key.name" : "object"
        }
      ],
      "key.name" : "Thing",
      "key.runtime_name" : "_TtC8__main__5Thing",
      "key.length" : 34
    },
    {
      "key.kind" : "source.lang.swift.decl.var.global",
      "key.offset" : 36,
      "key.nameoffset" : 40,
      "key.namelength" : 5,
      "key.length" : 19,
      "key.accessibility" : "source.lang.swift.accessibility.internal",
      "key.setter_accessibility" : "source.lang.swift.accessibility.internal",
      "key.typename" : "thing",
      "key.name" : "thing"
    },
    {
      "key.kind" : "source.lang.swift.expr.call",
      "key.offset" : 48,
      "key.nameoffset" : 48,
      "key.namelength" : 5,
      "key.bodyoffset" : 54,
      "key.bodylength" : 0,
      "key.length" : 7,
      "key.name" : "Thing"
    }
  ],
  "key.diagnostics" : [
    {
      "key.diagnostic_stage" : "source.diagnostic.stage.swift.parse",
      "key.description" : "expected member name following '.'",
      "key.severity" : "source.diagnostic.severity.error",
      "key.column" : 20,
      "key.filepath" : "--",
      "key.line" : 5
    }
  ],
  "key.offset" : 0,
  "key.diagnostic_stage" : "source.diagnostic.stage.swift.parse",
  "key.length" : 56
}

The important thing in the above is key.typename is "object". If you add in the explicit type:

class Thing {
    let object: Int = 5
}

Then the syntax command for key.typname is "Int"

I realize this would be a different type of parsing -- not only structure but also semantic analysis (which is I assume this code https://github.com/apple/swift/tree/master/lib/Sema). But I'm just curious if this is something that exists already in source kitten behind the scenes or if it would be a fully new thing.

Thanks!

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the existing sourcekitten structure --file command and compare its output for inferred and explicit property types. Review the referenced Swift lib/Sema area to determine whether inferred type information is already available; done means establishing a defined way for SourceKitten to expose it or documenting why it cannot.

Written by the indexing model from the issue text.

Assessment

Tech stack
swift
Domain
compilers, devtools
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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