8 files changed, 84 insertions, 0 deletions
diff --git a/autoload/ale/fix/registry.vim b/autoload/ale/fix/registry.vim
index a591a57b..23441ca5 100644
--- a/autoload/ale/fix/registry.vim
+++ b/autoload/ale/fix/registry.vim
@@ -216,6 +216,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['cmake'],
 \       'description': 'Fix CMake files with cmake-format.',
 \   },
+\   'fish_indent': {
+\       'function': 'ale#fixers#fish_indent#Fix',
+\       'suggested_filetypes': ['fish'],
+\       'description': 'Format fish scripts using fish_indent.',
+\   },
 \   'gofmt': {
 \       'function': 'ale#fixers#gofmt#Fix',
 \       'suggested_filetypes': ['go'],
diff --git a/autoload/ale/fixers/fish_indent.vim b/autoload/ale/fixers/fish_indent.vim
new file mode 100644
index 00000000..ebf17c5a
--- /dev/null
+++ b/autoload/ale/fixers/fish_indent.vim
@@ -0,0 +1,19 @@
+" Author: Chen YuanYuan <cyyever@outlook.com>
+" Description: Integration of fish_indent with ALE.
+
+call ale#Set('fish_fish_indent_executable', 'fish_indent')
+call ale#Set('fish_fish_indent_options', '')
+
+function! ale#fixers#fish_indent#Fix(buffer) abort
+    let l:executable = ale#Var(a:buffer, 'fish_fish_indent_executable')
+    let l:options = ale#Var(a:buffer, 'fish_fish_indent_options')
+    let l:filename = ale#Escape(bufname(a:buffer))
+
+    return {
+    \   'command': ale#Escape(l:executable)
+    \       . ' -w '
+    \       . (empty(l:options) ? '' : ' ' . l:options)
+    \       . ' %t',
+    \   'read_temporary_file': 1,
+    \}
+endfunction
diff --git a/doc/ale-fish.txt b/doc/ale-fish.txt
index 8450b38a..7dbbc10c 100644
--- a/doc/ale-fish.txt
+++ b/doc/ale-fish.txt
@@ -11,4 +11,21 @@ If ALE is not showing any errors but your file does not run as expected, run
 `fish -n <file.fish>` from the command line.
 
 ===============================================================================
+fish_indent                                               *ale-fish-fish_indent*
+
+g:ale_fish_fish_indent_executable            *g:ale_fish_fish_indent_executable*
+                                             *b:ale_fish_fish_indent_executable*
+  Type: |String|
+  Default: `'fish_indent'`
+
+  This variable can be changed to use a different executable for fish_indent.
+
+g:ale_fish_fish_indent_options                  *g:ale_fish_fish_indent_options*
+                                                *b:ale_fish_fish_indent_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be set to pass additional options to fish_indent.
+
+===============================================================================
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:
diff --git a/doc/ale-supported-languages-and-tools.txt b/doc/ale-supported-languages-and-tools.txt
index 72c685c5..33771e49 100644
--- a/doc/ale-supported-languages-and-tools.txt
+++ b/doc/ale-supported-languages-and-tools.txt
@@ -152,6 +152,7 @@ Notes:
   * `erlc`
 * Fish
   * `fish` (-n flag)
+  * `fish_indent`
 * Fortran
   * `gcc`
   * `language_server`
diff --git a/doc/ale.txt b/doc/ale.txt
index 9268c9f2..034d62b8 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -2699,6 +2699,7 @@ documented in additional help files.
   eruby...................................|ale-eruby-options|
     ruumba................................|ale-eruby-ruumba|
   fish....................................|ale-fish-options|
+    fish_indent...........................|ale-fish-fish_indent|
   fortran.................................|ale-fortran-options|
     gcc...................................|ale-fortran-gcc|
     language_server.......................|ale-fortran-language-server|
diff --git a/supported-tools.md b/supported-tools.md
index e449ff39..b649ec22 100644
--- a/supported-tools.md
+++ b/supported-tools.md
@@ -161,6 +161,7 @@ formatting.
   * [erlc](http://erlang.org/doc/man/erlc.html)
 * Fish
   * fish [-n flag](https://linux.die.net/man/1/fish)
+  * [fish_indent](https://fishshell.com/docs/current/cmds/fish_indent.html)
 * Fortran
   * [gcc](https://gcc.gnu.org/)
   * [language_server](https://github.com/hansec/fortran-language-server)
diff --git a/test/fish_files/testfile.fish b/test/fish_files/testfile.fish
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/test/fish_files/testfile.fish
diff --git a/test/fixers/test_fish_indent_fixer_callback.vader b/test/fixers/test_fish_indent_fixer_callback.vader
new file mode 100644
index 00000000..beb0b42e
--- /dev/null
+++ b/test/fixers/test_fish_indent_fixer_callback.vader
@@ -0,0 +1,40 @@
+Before:
+  Save g:ale_fish_fish_indent_executable
+  Save g:ale_fish_fish_indent_options
+
+  " Use an invalid global executable, so we don't match it.
+  let g:ale_fish_fish_indent_executable = 'xxxinvalid'
+  let g:ale_fish_fish_indent_options = ''
+
+  call ale#test#SetDirectory('/testplugin/test/fixers')
+
+After:
+  Restore
+
+  call ale#test#RestoreDirectory()
+
+Execute(The fish_indent callback should return the correct default values):
+  call ale#test#SetFilename('../fish_files/testfile.fish')
+
+  AssertEqual
+  \ {
+  \   'read_temporary_file': 1,
+  \   'command': ale#Escape('xxxinvalid')
+  \   . ' -w '
+  \   . ' %t',
+  \ },
+  \ ale#fixers#fish_indent#Fix(bufnr(''))
+
+Execute(The fish_indent callback should include custom fish_indent options):
+  let g:ale_fish_fish_indent_options = "-d"
+  call ale#test#SetFilename('../fish_files/testfile.fish')
+
+  AssertEqual
+  \ {
+  \   'read_temporary_file': 1,
+  \   'command': ale#Escape('xxxinvalid')
+  \   . ' -w '
+  \   . ' -d'
+  \   . ' %t',
+  \ },
+  \ ale#fixers#fish_indent#Fix(bufnr(''))