Function call parsed as a Type conversion

[aryx]

From semgrep/semgrep#3993

this program:

_ := os.GetEnv("Test")

without the ending newline is parsed as a type conversion instead of a regular function call.

[adonovan]

Perhaps it is a type conversion: you can't tell without seeing whether package os defines type GetEnv string or func GetEnv(string) string, and the parser is not privy to that information.

[aryx]

Still it's weird that a newline has an impact on how this thing is parsed.

[aryx]

And in any case, because tree-sitter does not have the information, it should parse it as a function call, not a cast.
It should return a Cast node when we know for sure the thing is a type, as in _ := int(3)

[dominikh]

@aryx

It should return a Cast node when we know for sure the thing is a type, as in _ := int(3)

Do note that even in that case, int could just as easily refer to a function that is shadowing the predeclared type int.