+Before:
+ runtime ale_linters/sh/shell.vim
+ runtime ale_linters/sh/shellcheck.vim
+
+After:
+ call ale#linter#Reset()
+
+ unlet! b:is_bash
+ unlet! b:is_sh
+ unlet! b:is_kornshell
+
+Given(A file with a Bash hashbang):
+ #!/bin/bash
+
+Execute(/bin/bash should be detected appropriately):
+ AssertEqual 'bash', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'bash', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'bash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with /bin/sh):
+ #!/usr/bin/env sh -eu --foobar
+
+Execute(/bin/sh should be detected appropriately):
+ AssertEqual 'sh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'sh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'sh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with bash as an argument to env):
+ #!/usr/bin/env bash
+
+Execute(/usr/bin/env bash should be detected appropriately):
+ AssertEqual 'bash', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'bash', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'bash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a tcsh hash bang and arguments):
+ #!/usr/bin/env tcsh -eu --foobar
+
+Execute(tcsh should be detected appropriately):
+ AssertEqual 'tcsh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'tcsh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'tcsh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a zsh hash bang and arguments):
+ #!/usr/bin/env zsh -eu --foobar
+
+Execute(zsh should be detected appropriately):
+ AssertEqual 'zsh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'zsh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'zsh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a csh hash bang and arguments):
+ #!/usr/bin/env csh -eu --foobar
+
+Execute(csh should be detected appropriately):
+ AssertEqual 'csh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'csh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'csh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a ksh hashbang):
+ #!/bin/ksh
+
+Execute(/bin/ksh should be detected appropriately):
+ AssertEqual 'ksh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'ksh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'ksh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a ksh as an argument to env):
+ #!/usr/bin/env ksh
+
+Execute(ksh should be detected appropriately):
+ AssertEqual 'ksh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'ksh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'ksh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a sh hash bang and arguments):
+ #!/usr/bin/env sh -eu --foobar
+
+Execute(sh should be detected appropriately):
+ AssertEqual 'sh', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'sh', ale_linters#sh#shell#GetExecutable(bufnr(''))
+ AssertEqual 'sh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file without a hashbang):
+
+Execute(The bash dialect should be used for shellcheck if b:is_bash is 1):
+ let b:is_bash = 1
+
+ AssertEqual 'bash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Execute(The sh dialect should be used for shellcheck if b:is_sh is 1):
+ let b:is_sh = 1
+
+ AssertEqual 'sh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Execute(The ksh dialect should be used for shellcheck if b:is_kornshell is 1):
+ let b:is_kornshell = 1
+
+ AssertEqual 'ksh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Execute(The filetype should be used as the default shell type when there is no hashbang line):
+ set filetype=zsh
+ AssertEqual 'zsh', ale#handlers#sh#GetShellType(bufnr(''))
+
+ set filetype=tcsh
+ AssertEqual 'tcsh', ale#handlers#sh#GetShellType(bufnr(''))
+
+ set filetype=python
+ AssertEqual '', ale#handlers#sh#GetShellType(bufnr(''))
+
+Given(A file with /bin/ash):
+ #!/bin/ash
+
+Execute(The ash dialect should be used for the shell and the base function):
+ AssertEqual 'ash', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'ash', ale_linters#sh#shell#GetExecutable(bufnr(''))
+
+Execute(dash should be used for shellcheck, which has no ash dialect):
+ AssertEqual 'dash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with /bin/dash):
+ #!/bin/dash
+
+Execute(The dash dialect should be used for the shell and the base function):
+ AssertEqual 'dash', ale#handlers#sh#GetShellType(bufnr(''))
+ AssertEqual 'dash', ale_linters#sh#shell#GetExecutable(bufnr(''))
+
+Execute(dash should be used for shellcheck):
+ AssertEqual 'dash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a Bash shellcheck shell directive):
+ # shellcheck shell=bash
+
+Execute(bash dialect should be detected appropriately):
+ AssertEqual 'bash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a sh shellcheck shell directive):
+ #shellcheck shell=sh
+
+Execute(sh dialect should be detected appropriately):
+ AssertEqual 'sh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a tcsh shellcheck shell directive):
+ # shellcheck shell=tcsh
+
+Execute(tcsh dialect should be detected appropriately):
+ AssertEqual 'tcsh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a zsh shellcheck shell directive):
+ # shellcheck shell=zsh
+
+Execute(zsh dialect should be detected appropriately):
+ AssertEqual 'zsh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a csh shellcheck shell directive):
+ # shellcheck shell=csh
+
+Execute(zsh dialect should be detected appropriately):
+ AssertEqual 'csh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a ksh shellcheck shell directive):
+ # shellcheck shell=ksh
+
+Execute(ksh dialect should be detected appropriately):
+ AssertEqual 'ksh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a dash shellcheck shell directive):
+ # shellcheck shell=dash
+
+Execute(dash dialect should be detected appropriately):
+ AssertEqual 'dash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
+
+Given(A file with a ash shellcheck shell directive):
+ # shellcheck shell=ash
+
+Execute(dash dialect should be detected for ash that shellcheck does not support):
+ AssertEqual 'dash', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))