TSServer navtree — Way to differentiate function declarations from function expressions

TypeScript Version: 3.3.0-dev.20181214

Search Terms:

• tsserver
• navtree

Problem
For https://github.com/Microsoft/vscode/issues/22981, we'd like a way to differentiate function delcarations from function expressions. Consider a file:

function foo(f) { }

foo(function bar() { })

const car = function dar(f) { }

VS Code uses the navtree to get possible code lens locations. We would only like to show references code lenses on function foo and perhaps on const car =, not on the expression foo(function bar() {}).

Using the navtree request against the TS Server, we cannot tell function declarations like foo from function expressions like bar :

 {
            "text": "bar",
            "kind": "function",
            "kindModifiers": "",
            "spans": [
                {
                    "start": {
                        "line": 3,
                        "offset": 5
                    },
                    "end": {
                        "line": 3,
                        "offset": 23
                    }
                }
            ],
            "nameSpan": {
                "start": {
                    "line": 3,
                    "offset": 14
                },
                "end": {
                    "line": 3,
                    "offset": 17
                }
            }
        },
        {
            "text": "dar",
            "kind": "function",
            "kindModifiers": "",
            "spans": [
                {
                    "start": {
                        "line": 5,
                        "offset": 13
                    },
                    "end": {
                        "line": 5,
                        "offset": 32
                    }
                }
            ],
            "nameSpan": {
                "start": {
                    "line": 5,
                    "offset": 22
                },
                "end": {
                    "line": 5,
                    "offset": 25
                }
            }
        },
        {
            "text": "foo",
            "kind": "function",
            "kindModifiers": "",
            "spans": [
                {
                    "start": {
                        "line": 1,
                        "offset": 1
                    },
                    "end": {
                        "line": 1,
                        "offset": 20
                    }
                }
            ],
            "nameSpan": {
                "start": {
                    "line": 1,
                    "offset": 10
                },
                "end": {
                    "line": 1,
                    "offset": 13
                }
            }
        }
    ]

Proposal
Differentiate:

function foo(f) { }

by using a kindModifier of "definition" or a similar name (or do the inverse and mark function bar() { } with a kindModifier of "expression")

Also, we correctly differentiate car using "kind": "const" in the case of:

const car = function(f) { }

However only dar is returned for for:

const car = function dar(f) { }

Inizia tracciando la richiesta navtree di tsserver e la costruzione della relativa risposta, usando come comportamento atteso gli esempi riportati di dichiarazione di funzione ed espressione di funzione. Determina dove vengono assegnati kind e kindModifiers, quindi verifica che la risposta distingua le dichiarazioni dalle espressioni, comprese le funzioni denominate assegnate a variabili const.