Long running 'completions' request on TS project using lodash

[mjbvz]

From microsoft/vscode#47253 (comment)

TypeScript Version: 2.9.0-dev.20180409

Search Terms:

• completions

Code
In a new folder without a tsconfig:

package.json:

{
  "name": "test",
  "private": true,
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@types/lodash": "^4.14.106",
    "lodash": "^4.17.5",
    "typescript": "^2.9.0-dev.20180409"
  }
}

index.ts:

import * as _ from 'lodash';

const result = _.chain([]).ma
// or
const result = _([]).ma

1. Run npm install
2. Open index.ts in vscode
3. Trigger completions on .ma

Bug:
TS Server completions requests end up taking ~6seconds each time. Here's my tsserver log
tsserver copy.log

Look for the lines around: getCompletionData: Semantic work: 6974

Probably a duplicate of #21968

[sheetalkamat]

Looks like we are spending lot of time in isTypeAssignableTo for conforms, flow, flowRight and such which is in multiple seconds and then there are few where we are spending time in three digit miliseconds

Info 82   [16:0:1.532] getCompletionData: IsValidTime: 8756 addPropertySymbolTime: 1

Info 1907 [16:0:1.557] getCompletionData:: conforms isValidPropertyAccessWithType::getPropertyOfType :: 0
Info 1908 [16:0:1.557] getCompletionData:: conforms isValidPropertyAccessWithType::checkPropertyAccessibility :: 0
Info 1909 [16:0:1.557] getCompletionData:: conforms isValidMethodAccess::getTypeOfFuncClassEnumModule :: 0
Info 1910 [16:0:1.557] getCompletionData:: conforms isValidMethodAccess::getSignaturesOfType :: 0
Info 1911 [16:0:1.557] getCompletionData:: conforms isValidMethodAccess:: getThisTypeOfSignature :: 0
Info 1912 [16:0:1.557] getCompletionData:: conforms isValidMethodAccess:: isTypeAssignableTo :: 2636
Info 1913 [16:0:1.557] getCompletionData:: conforms isValidMethodAccess::[{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":2636}] :: 0

Info 1928 [16:0:1.557] getCompletionData:: flow isValidPropertyAccessWithType::getPropertyOfType :: 0
Info 1929 [16:0:1.557] getCompletionData:: flow isValidPropertyAccessWithType::checkPropertyAccessibility :: 0
Info 1930 [16:0:1.557] getCompletionData:: flow isValidMethodAccess::getTypeOfFuncClassEnumModule :: 0
Info 1931 [16:0:1.557] getCompletionData:: flow isValidMethodAccess::getSignaturesOfType :: 0
Info 1932 [16:0:1.557] getCompletionData:: flow isValidMethodAccess:: getThisTypeOfSignature :: 7
Info 1933 [16:0:1.557] getCompletionData:: flow isValidMethodAccess:: isTypeAssignableTo :: 2681
Info 1934 [16:0:1.557] getCompletionData:: flow isValidMethodAccess::[{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":111},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":92},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":31},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":62},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":55},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":58},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":27},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":53},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":60},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":62},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":63},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":31},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":73},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":81},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":57},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":29},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":70},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":75},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":51},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":55},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":24},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":66},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":61},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":64},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":27},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":59},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":61},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":65},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":66},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":28},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":68},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":65},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":68},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":26},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":75},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":73},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":70},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":26},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":73},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":95},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":129},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":145},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":51}] :: 0

Info 1935 [16:0:1.557] getCompletionData:: flowRight isValidPropertyAccessWithType::getPropertyOfType :: 0
Info 1936 [16:0:1.557] getCompletionData:: flowRight isValidPropertyAccessWithType::checkPropertyAccessibility :: 0
Info 1937 [16:0:1.557] getCompletionData:: flowRight isValidMethodAccess::getTypeOfFuncClassEnumModule :: 0
Info 1938 [16:0:1.557] getCompletionData:: flowRight isValidMethodAccess::getSignaturesOfType :: 0
Info 1939 [16:0:1.557] getCompletionData:: flowRight isValidMethodAccess:: getThisTypeOfSignature :: 4
Info 1940 [16:0:1.557] getCompletionData:: flowRight isValidMethodAccess:: isTypeAssignableTo :: 2312
Info 1941 [16:0:1.557] getCompletionData:: flowRight isValidMethodAccess::[{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":74},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":78},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":68},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":19},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":58},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":70},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":71},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":69},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":28},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":65},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":86},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":81},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":25},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":69},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":69},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":70},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":23},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":75},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":69},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":72},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":66},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":22},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":66},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":66},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":68},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":21},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":69},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":66},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":69},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":74},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":26},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":89},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":72},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":67},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":20},{"signatureThisType":true,"getThisTypeOfSignature":1,"isTypeAssignableTo":67},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":72},{"signatureThisType":true,"getThisTypeOfSignature":0,"isTypeAssignableTo":73}] :: 0

Used branch https://github.com/Microsoft/TypeScript/tree/completionLodashPerfInvestigation for these extra debug info and used code and package.json mentioned in repro for this analysis.

[sheetalkamat]

@weswigham can you take a look if we can do something better with isTypeAssignableTo in this case? U think we spend time to compare this types that say no is isn't assignable for these methods (to not show them in the completion)