#+TITLE:   completion/ivy
#+DATE:    February 13, 2017
#+SINCE:   v2.0
#+STARTUP: inlineimages

* Table of Contents :TOC_3:noexport:
- [[#description][Description]]
  - [[#module-flags][Module Flags]]
  - [[#plugins][Plugins]]
  - [[#hacks][Hacks]]
- [[#prerequisites][Prerequisites]]
  - [[#install][Install]]
    - [[#macos][MacOS]]
    - [[#arch-linux][Arch Linux]]
- [[#features][Features]]
  - [[#jump-to-file-project-navigation][Jump-to-file project navigation]]
  - [[#project-search--replace][Project search & replace]]
  - [[#in-buffer-searching][In-buffer searching]]
  - [[#task-lookup][Task lookup]]
  - [[#ivy-integration-for-various-completing-commands][Ivy integration for various completing commands]]
    - [[#general][General]]
    - [[#jump-to-files-buffers-or-projects][Jump to files, buffers or projects)]]
    - [[#search][Search]]
- [[#configuration][Configuration]]
  - [[#enable-fuzzynon-fuzzy-search-for-specific-commands][Enable fuzzy/non-fuzzy search for specific commands]]
  - [[#change-the-position-of-the-ivy-childframe][Change the position of the ivy childframe]]
- [[#troubleshooting][Troubleshooting]]

* Description
This module provides Ivy integration for a variety of Emacs commands, as well as
a unified interface for project search and replace, powered by ag, rg, pt,
git-grep & grep (whichever is available).

#+begin_quote
I prefer ivy over ido for its flexibility. I prefer ivy over helm because it's
lighter, simpler and faster in many cases.
#+end_quote

** Module Flags
+ =+fuzzy= Enables fuzzy completion for Ivy searches.
+ =+prescient= Enables prescient filtering and sorting for Ivy searches.
+ =+childframe= Causes Ivy to display in a floating child frame, above Emacs.
  *This requires GUI Emacs 26.1+*
+ =+icons= Enables file icons for switch-{buffer,project}/find-file counsel
  commands.

** Plugins
+ [[https://github.com/abo-abo/swiper][ivy]]
+ [[https://github.com/abo-abo/swiper][counsel]]
+ [[https://github.com/ericdanan/counsel-projectile][counsel-projectile]]
+ [[https://github.com/abo-abo/swiper][swiper]]
+ [[https://github.com/abo-abo/swiper][ivy-hydra]]
+ [[https://github.com/yevgnen/ivy-rich][ivy-rich]]
+ [[https://github.com/mhayashi1120/Emacs-wgrep][wgrep]]
+ [[https://github.com/DarwinAwardWinner/amx][amx]]
+ [[https://github.com/lewang/flx][flx]]* (=+fuzzy=)
+ [[https://github.com/raxod502/prescient.el][prescient]]* (=+prescient=)
+ [[https://github.com/tumashu/ivy-posframe][ivy-posframe]]* (=+childframe=)
+ [[https://github.com/asok/all-the-icons-ivy][all-the-icons-ivy]]* (=+icons=)

** Hacks
+ Functions with ivy/counsel equivalents have been globally remapped (like
  ~find-file~ => ~counsel-find-file~). So a keybinding to ~find-file~ will
  invoke ~counsel-find-file~ instead.
+ ~counsel-[arp]g~'s 3-character limit was reduced to 1 (mainly for the ex
  command)

* Prerequisites
This module optionally depends on one of:

+ [[https://github.com/BurntSushi/ripgrep][ripgrep]] (rg)
+ [[https://github.com/ggreer/the_silver_searcher][the_silver_searcher]] (ag)
+ [[https://github.com/monochromegane/the_platinum_searcher][the_platinum_searcher]] (pt)

Ripgrep is recommended, but the order of its results aren't deterministic and it
doesn't support full PCRE (at the time of writing). The_silver_searcher is a
good alternative if either of these bother you.

If none of these are installed, file search commands will use git-grep (falling
back to grep, otherwise).

** Install
*** MacOS
#+BEGIN_SRC sh
brew install ripgrep the_silver_searcher
#+END_SRC

*** Arch Linux
#+BEGIN_SRC sh :dir /sudo::
sudo pacman --needed --noconfirm -S ripgrep the_silver_searcher
#+END_SRC

* Features
Ivy and its ilk are large plugins. Covering everything about them is outside of
this documentation's scope, so only Doom-specific Ivy features are listed here:

** Jump-to-file project navigation
Inspired by Sublime Text's jump-to-anywhere, CtrlP/Unite in Vim, and Textmate's
Command-T, this module provides similar functionality by bringing ~projectile~
and ~ivy~ together.

https://assets.doomemacs.org/completion/ivy/projectile.png

| Keybind              | Description                         |
|----------------------+-------------------------------------|
| =SPC f /=, =SPC SPC= | Jump to file in project             |
| =SPC f .=, =SPC .=   | Jump to file from current directory |

** Project search & replace
This module provides interactive text search and replace using the first search
program available on your system (rg, ag, pt, git-grep or grep).

| Keybind   | Description                     |
|-----------+---------------------------------|
| =SPC / b= | Search the current buffer       |
| =SPC / p= | Search project                  |
| =SPC / d= | Search this directory           |
| =SPC p t= | List all TODO/FIXMEs in project |

https://assets.doomemacs.org/completion/ivy/search.png

The ~+ivy-project-search-engines~ variable is consulted to determine which
underlying program to check for (and in what order). It's default value is ~'(rg
ag pt)~. If none of these are available, it will resort to =git-grep= (falling
back to =grep= after that).

To use a specific program, the following engine-specific commands are available
(but not bound to any key by default) for searching from the project root or the
current directory (recursively), respectively:

+ ~+ivy/ag~ / ~+ivy/ag-from-cwd~
+ ~+ivy/rg~ / ~+ivy/rg-from-cwd~
+ ~+ivy/pt~ / ~+ivy/pt-from-cwd~
+ ~+ivy/grep~ / ~+ivy/grep-from-cwd~

The universal argument (=SPC u= for evil users; =C-u= otherwise) changes the
behavior of these commands, instructing the underlying search engine to include
ignored files.

This module also provides Ex Commands for evil users:

| Ex command            | Description                                    |
|-----------------------+------------------------------------------------|
| ~:ag[!] [QUERY]~      | Search project w/ ag[fn:1]                     |
| ~:rg[!] [QUERY]~      | Search project w/ rg[fn:1]                     |
| ~:pt[!] [QUERY]~      | Search project w/ pt[fn:1]                     |
| ~:grep[!] [QUERY]~    | Search project w/ git-grep/grep[fn:1]          |
| ~:agcwd[!] [QUERY]~   | Search this directory w/ the_silver_searcher   |
| ~:rgcwd[!] [QUERY]~   | Search this directory w/ ripgrep               |
| ~:ptcwd[!] [QUERY]~   | Search this directory w/ the_platinum_searcher |
| ~:grepcwd[!] [QUERY]~ | Search this directory w/ git-grep/grep         |

The optional BANG functions is equivalent to the universal argument for the
previous commands.

-----

While in a search (e.g. invoked from ~+ivy:ag~ or ~:rg~), these extra
keybindings are available to you:

| Keybind   | Description                                   |
|-----------+-----------------------------------------------|
| =C-c C-e= | Open a writable buffer of your search results |
| =C-SPC=   | Preview the current candidate                 |
| =M-RET=   | Open the selected candidate in other-window   |

Changes to the resulting wgrep buffer (opened by =C-c C-e=) can be committed
with =C-c C-c= and aborted with =C-c C-k= (alternatively =ZZ= and =ZQ=, for evil
users).

https://assets.doomemacs.org/completion/ivy/search-replace.png

** In-buffer searching
The =swiper= package provides an interactive buffer search powered by ivy. It
can be invoked with:

+ =SPC / b=
+ ~:sw[iper] [QUERY]~

https://assets.doomemacs.org/completion/ivy/swiper.png

A wgrep buffer can be opened from swiper with =C-c C-e=.

** Task lookup
Some projects have TODO's and FIXME's littered across them. The ~+ivy/tasks~
command allows you to search and jump to them. It can be invoked with:

+ =SPC p t= (C-u = restrict search to current file)
+ ~:todo[!]~ (BANG = restrict search to current file)

https://assets.doomemacs.org/completion/ivy/todo.png

** Ivy integration for various completing commands
*** General
| Keybind        | Description               |
|----------------+---------------------------|
| =M-x=, =SPC := | Smarter, smex-powered M-x |
| =SPC '=        | Resume last ivy session   |

*** Jump to files, buffers or projects)
| Keybind                         | Description                           |
|---------------------------------+---------------------------------------|
| =SPC RET=                       | Find bookmark                         |
| =SPC f .=, =SPC .=              | Browse from current directory         |
| =SPC f /=, =SPC p /=, =SPC SPC= | Find file in project                  |
| =SPC f r=                       | Find recently opened file             |
| =SPC p p=                       | Open another project                  |
| =SPC b b=, =SPC ,=              | Switch to buffer in current workspace |
| =SPC b B=, =SPC <=              | Switch to buffer                      |

*** Search
| Keybind   | Description                              |
|-----------+------------------------------------------|
| =SPC / i= | Search for symbol in current buffer      |
| =SPC / I= | Search for symbol in all similar buffers |
| =SPC / b= | Search the current buffer                |
| =SPC / p= | Search project                           |
| =SPC / d= | Search this directory                    |
| =SPC p t= | List all TODO/FIXMEs in project          |

* Configuration
** TODO Enable fuzzy/non-fuzzy search for specific commands
** TODO Change the position of the ivy childframe

* TODO Troubleshooting