This CL teaches lsp to report `**T` instead of `**invalid type`,
`func (badParam) badResult` instead of `func (invalid type) invalid type`, etc.
To do that, we need to detect "invalid type" inside any part of a type.
I've added typeIsValid() function for that.
To simplify type formating code in resolveInvalid(), formatNode
function is added that can also format *ast.StarExpr (of any depth).
Since we already used AST printer in the same file, I
added formatNode function that is now used in both places.
While at it, replaced bytes.Buffer to strings.Builder there.
Change-Id: I3bb84c58c417b175cceefb410e238c48425f7cee
Reviewed-on: https://go-review.googlesource.com/c/tools/+/210357
Run-TryBot: Iskander Sharipov <quasilyte@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
ec14b29651