`prettier.format()` slow for deeply nested function calls in input string

[tony19]

When the input string contains many (about 25) nested function calls in JavaScript, prettier.format() takes about 2.5 minutes to return. This seems to occur when coreFormat() converts the AST to a document (in printAstToDoc()).

Environment:

• macOS High Sierra 10.13.4
• Node 8.9.4 and 9.11.1
• MacBook Pro 2017, 2.7GHz i7, 16GB 2133MHz LPDDR3

Prettier 1.13.5
Playground link

Input:

_c("div", [
  _c("div", [
    _c("div", [
      _c("div", [
        _c("div", [
          _c("div", [
            _c("div", [
              _c("div", [
                _c("div", [
                  _c("div", [
                    _c("div", [
                      _c("div", [
                        _c("div", [
                          _c("div", [
                            _c("div", [
                              _c("div", [
                                _c("div", [
                                  _c("div", [
                                    _c("div", [
                                      _c("div", [
                                        _c("div", [
                                          _c("div", [
                                            _c("div", [_c("div", [_c("div")])])
                                          ])
                                        ])
                                      ])
                                    ])
                                  ])
                                ])
                              ])
                            ])
                          ])
                        ])
                      ])
                    ])
                  ])
                ])
              ])
            ])
          ])
        ])
      ])
    ])
  ])
])

Output:
(same as input after 159 seconds)

Expected behavior:
prettier.format(input) returns within a few seconds (much sooner than 159 seconds)

[tony19]

Possibly related to #1250 and #2259

[fisker]

This is not slow anymore, not sure how and when it got improved

[thorn0]

#6229 fixed it most probably.