You can definitely write a tool to do it for JavaScript.
Sublime text has something similar that gives you the usages of a function when you hover over its name. Its not as 100 percent accurate as strict static code analysis, but it works pretty well for function names that are not duplicated everywhere.
Sublime text has something similar that gives you the usages of a function when you hover over its name. Its not as 100 percent accurate as strict static code analysis, but it works pretty well for function names that are not duplicated everywhere.