Run ESLint fixer from project root, where possible (#3096)

* Split eslint#GetCdString from eslint#GetCommand

Move the code for finding the project root and building the cd string
into a separate function so that it can be reused in the eslint fixer.

Signed-off-by: Kevin Locke <kevin@kevinlocke.name>

* Run ESLint fixer from project root dir

To match the ESLint linter, as changed in 9ee57d43 (which I forgot to
apply to the fixer, whoops).

Fixes: #3094
Closes: #3095

Signed-off-by: Kevin Locke <kevin@kevinlocke.name>

3 files changed, 50 insertions, 22 deletions

diff --git a/autoload/ale/fixers/eslint.vim b/autoload/ale/fixers/eslint.vim
index 62e692b1..f725875c 100644
--- a/autoload/ale/fixers/eslint.vim
+++ b/autoload/ale/fixers/eslint.vim
@@ -53,7 +53,8 @@ function! ale#fixers#eslint#ApplyFixForVersion(buffer, version) abort
     " Use --fix-to-stdout with eslint_d
     if l:executable =~# 'eslint_d$' && ale#semver#GTE(a:version, [3, 19, 0])
         return {
-        \   'command': ale#node#Executable(a:buffer, l:executable)
+        \   'command': ale#handlers#eslint#GetCdString(a:buffer)
+        \       . ale#node#Executable(a:buffer, l:executable)
         \       . ale#Pad(l:options)
         \       . ' --stdin-filename %s --stdin --fix-to-stdout',
         \   'process_with': 'ale#fixers#eslint#ProcessEslintDOutput',
@@ -63,7 +64,8 @@ function! ale#fixers#eslint#ApplyFixForVersion(buffer, version) abort
     " 4.9.0 is the first version with --fix-dry-run
     if ale#semver#GTE(a:version, [4, 9, 0])
         return {
-        \   'command': ale#node#Executable(a:buffer, l:executable)
+        \   'command': ale#handlers#eslint#GetCdString(a:buffer)
+        \       . ale#node#Executable(a:buffer, l:executable)
         \       . ale#Pad(l:options)
         \       . ' --stdin-filename %s --stdin --fix-dry-run --format=json',
         \   'process_with': 'ale#fixers#eslint#ProcessFixDryRunOutput',
@@ -71,7 +73,8 @@ function! ale#fixers#eslint#ApplyFixForVersion(buffer, version) abort
     endif
 
     return {
-    \   'command': ale#node#Executable(a:buffer, l:executable)
+    \   'command': ale#handlers#eslint#GetCdString(a:buffer)
+    \       . ale#node#Executable(a:buffer, l:executable)
     \       . ale#Pad(l:options)
     \       . (!empty(l:config) ? ' -c ' . ale#Escape(l:config) : '')
     \       . ' --fix %t',
diff --git a/autoload/ale/handlers/eslint.vim b/autoload/ale/handlers/eslint.vim
index 156b939f..c7c47d78 100644
--- a/autoload/ale/handlers/eslint.vim
+++ b/autoload/ale/handlers/eslint.vim
@@ -37,11 +37,9 @@ function! ale#handlers#eslint#GetExecutable(buffer) abort
     \])
 endfunction
 
-function! ale#handlers#eslint#GetCommand(buffer) abort
-    let l:executable = ale#handlers#eslint#GetExecutable(a:buffer)
-
-    let l:options = ale#Var(a:buffer, 'javascript_eslint_options')
-
+" Given a buffer, return a command prefix string which changes directory
+" as necessary for running ESLint.
+function! ale#handlers#eslint#GetCdString(buffer) abort
     " ESLint 6 loads plugins/configs/parsers from the project root
     " By default, the project root is simply the CWD of the running process.
     " https://github.com/eslint/rfcs/blob/master/designs/2018-simplified-package-loading/README.md
@@ -50,9 +48,16 @@ function! ale#handlers#eslint#GetCommand(buffer) abort
     " Note: If node_modules not present yet, can't load local deps anyway.
     let l:modules_dir = ale#path#FindNearestDirectory(a:buffer, 'node_modules')
     let l:project_dir = !empty(l:modules_dir) ? fnamemodify(l:modules_dir, ':h:h') : ''
-    let l:cd_command = !empty(l:project_dir) ? ale#path#CdString(l:project_dir) : ''
 
-    return l:cd_command
+    return !empty(l:project_dir) ? ale#path#CdString(l:project_dir) : ''
+endfunction
+
+function! ale#handlers#eslint#GetCommand(buffer) abort
+    let l:executable = ale#handlers#eslint#GetExecutable(a:buffer)
+
+    let l:options = ale#Var(a:buffer, 'javascript_eslint_options')
+
+    return ale#handlers#eslint#GetCdString(a:buffer)
     \   . ale#node#Executable(a:buffer, l:executable)
     \   . (!empty(l:options) ? ' ' . l:options : '')
     \   . ' -f json --stdin --stdin-filename %s'
diff --git a/test/fixers/test_eslint_fixer_callback.vader b/test/fixers/test_eslint_fixer_callback.vader
index ad80bdd5..400267ac 100644
--- a/test/fixers/test_eslint_fixer_callback.vader
+++ b/test/fixers/test_eslint_fixer_callback.vader
@@ -13,7 +13,9 @@ Execute(The executable path should be correct):
   AssertFixer
   \ {
   \   'read_temporary_file': 1,
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' -c ' . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/.eslintrc.js'))
   \     . ' --fix %t',
@@ -150,7 +152,9 @@ Execute(The lower priority configuration file in a nested directory should be pr
   AssertFixer
   \ {
   \   'read_temporary_file': 1,
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' -c ' . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/subdir-with-config/.eslintrc'))
   \     . ' --fix %t',
@@ -164,7 +168,9 @@ Execute(--config in options should override configuration file detection for old
   AssertFixer
   \ {
   \   'read_temporary_file': 1,
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' --config /foo.cfg'
   \     . ' --fix %t',
@@ -175,7 +181,9 @@ Execute(--config in options should override configuration file detection for old
   AssertFixer
   \ {
   \   'read_temporary_file': 1,
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' -c /foo.cfg'
   \     . ' --fix %t',
@@ -187,7 +195,9 @@ Execute(package.json should be used as a last resort):
   AssertFixer
   \ {
   \   'read_temporary_file': 1,
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' -c ' . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/.eslintrc.js'))
   \     . ' --fix %t',
@@ -199,7 +209,8 @@ Execute(package.json should be used as a last resort):
   \ {
   \   'read_temporary_file': 1,
   \   'command':
-  \     ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/node_modules/.bin/eslint'))
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files'))
+  \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/node_modules/.bin/eslint'))
   \     . ' -c ' . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/package.json'))
   \     . ' --fix %t',
   \ }
@@ -214,7 +225,9 @@ Execute(The version check should be correct):
   \   . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \   . ' --version',
   \ {
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' --stdin-filename %s --stdin --fix-dry-run --format=json',
   \   'process_with': 'ale#fixers#eslint#ProcessFixDryRunOutput',
@@ -223,7 +236,9 @@ Execute(The version check should be correct):
 
   AssertFixer [
   \ {
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' --stdin-filename %s --stdin --fix-dry-run --format=json',
   \   'process_with': 'ale#fixers#eslint#ProcessFixDryRunOutput',
@@ -236,7 +251,9 @@ Execute(--fix-dry-run should be used for 4.9.0 and up):
   GivenCommandOutput ['4.9.0']
   AssertFixer
   \ {
-  \   'command': (has('win32') ? 'node.exe ' : '')
+  \   'command':
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app'))
+  \     . (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/eslint/bin/eslint.js'))
   \     . ' --stdin-filename %s --stdin --fix-dry-run --format=json',
   \   'process_with': 'ale#fixers#eslint#ProcessFixDryRunOutput',
@@ -249,7 +266,8 @@ Execute(--fix-to-stdout should be used for eslint_d):
   \ {
   \   'read_temporary_file': 1,
   \   'command':
-  \     ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d/node_modules/.bin/eslint_d'))
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d'))
+  \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d/node_modules/.bin/eslint_d'))
   \     . ' -c ' . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/package.json'))
   \     . ' --fix %t',
   \ }
@@ -260,7 +278,8 @@ Execute(--fix-to-stdout should be used for eslint_d):
   AssertFixer
   \ {
   \   'command':
-  \     ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d/node_modules/.bin/eslint_d'))
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d'))
+  \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d/node_modules/.bin/eslint_d'))
   \     . ' --stdin-filename %s --stdin --fix-to-stdout',
   \   'process_with': 'ale#fixers#eslint#ProcessEslintDOutput',
   \ }
@@ -270,7 +289,8 @@ Execute(--fix-to-stdout should be used for eslint_d):
   AssertFixer
   \ {
   \   'command':
-  \     ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d/node_modules/.bin/eslint_d'))
+  \     ale#path#CdString(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d'))
+  \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/app-with-eslint-d/node_modules/.bin/eslint_d'))
   \     . ' --stdin-filename %s --stdin --fix-to-stdout',
   \   'process_with': 'ale#fixers#eslint#ProcessEslintDOutput',
   \ }