Support function expressions and arrow functions in .call template

[Copilot]

Plan to support function declarations with .call template

• Understand current implementation of CallTemplate
• Modify CallTemplate.canUse() to allow function expressions and arrow functions
• Add test cases for async function expressions
• Add test cases for async arrow functions
• Add test cases for regular function expressions
• Add test cases for regular arrow functions
• Add template usage tests for function expressions
• Add multiline test for call template
• Address code review feedback
• Run final code review
• Run security checks
• Remove package-lock.json changes

Summary

Successfully implemented support for function expressions and arrow functions in the .call postfix template. The implementation:

• Adds two new type checks to CallTemplate.canUse() for function expressions and arrow functions
• Includes comprehensive test coverage for all variants (regular and async) in both single-line and multiline tests
• Passes all linting, compilation, code review, and security checks
• Maintains minimal and surgical changes to the codebase
• Reverted unintended package-lock.json changes

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Support function declaration</issue_title>
<issue_description>Please consider supporting the following usage.

async function() {
}.
  call

// result
(async function() {
})

async ()=> {
}.
  call

// result
(async ()=> {
})

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Support function declaration #117

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[ipatalas]

@copilot please also add one test in extension.multiline.test.ts

[Copilot]

@copilot please also add one test in extension.multiline.test.ts

Added multiline test for async function expression with .call template in commit 140a6d2.