function canFix(node) {
			const variables = sourceCode.getDeclaredVariables(node);
			const scopeNode = getScopeNode(node);

			if (
				node.parent.type === "SwitchCase" ||
				node.declarations.some(hasSelfReferenceInTDZ) ||
				variables.some(isGlobal) ||
				variables.some(isRedeclared) ||
				variables.some(isUsedFromOutsideOf(scopeNode)) ||
				variables.some(hasNameDisallowedForLetDeclarations)
			) {
				return false;
			}

			if (astUtils.isInLoop(node)) {
				if (variables.some(isReferencedInClosure)) {
					return false;
				}
				if (!isLoopAssignee(node) && !isDeclarationInitialized(node)) {
					return false;
				}
			}

			if (
				!isLoopAssignee(node) &&
				!(
					node.parent.type === "ForStatement" &&
					node.parent.init === node
				) &&
				!astUtils.STATEMENT_LIST_PARENTS.has(node.parent.type)
			) {
				// If the declaration is not in a block, e.g. `if (foo) var bar = 1;`, then it can't be fixed.
				return false;
			}

			return true;
		}
Checks whether it can fix a given variable declaration or not.
It cannot fix if the following cases:

- A variable is a global variable.
- A variable is declared on a SwitchCase node.
- A variable is redeclared.
- A variable is used from outside the scope.
- A variable is used from a closure within a loop.
- A variable might be used before it is assigned within a loop.
- A variable might be used in TDZ.
- A variable is declared in statement position (e.g. a single-line `IfStatement`)
- A variable has name that is disallowed for `let` declarations.

## A variable is declared on a SwitchCase node.

If this rule modifies 'var' declarations on a SwitchCase node, it
would generate the warnings of 'no-case-declarations' rule. And the
'eslint:recommended' preset includes 'no-case-declarations' rule, so
this rule doesn't modify those declarations.

## A variable is redeclared.

The language spec disallows redeclarations of `let` declarations.
Those variables would cause syntax errors.

## A variable is used from outside the scope.

The language spec disallows accesses from outside of the scope for
`let` declarations. Those variables would cause reference errors.

## A variable is used from a closure within a loop.

A `var` declaration within a loop shares the same variable instance
across all loop iterations, while a `let` declaration creates a new
instance for each iteration. This means if a variable in a loop is
referenced by any closure, changing it from `var` to `let` would
change the behavior in a way that is generally unsafe.

## A variable might be used before it is assigned within a loop.

Within a loop, a `let` declaration without an initializer will be
initialized to null, while a `var` declaration will retain its value
from the previous iteration, so it is only safe to change `var` to
`let` if we can statically determine that the variable is always
assigned a value before its first access in the loop body. To keep
the implementation simple, we only convert `var` to `let` within
loops when the variable is a loop assignee or the declaration has an
initializer.
@param {ASTNode} node A variable declaration node to check.
@returns {boolean} `true` if it can fix the node.