Fix #4388: Fix pylsp and Pyright cwd

Add functions to compute the cwd to be the same as the project root for
pylsp and Pyright to work around issues in each language server when
they encounter modules that share the same name as first or third party
libraries.

ale_linters/python/pylsp.vim

@@ -22,6 +22,19 @@ function! ale_linters#python#pylsp#GetExecutable(buffer) abort
     return ale#python#FindExecutable(a:buffer, 'python_pylsp', ['pylsp'])
 endfunction
 
+" Force the cwd of the server to be the same as the project root to
+" fix issues with treating local files matching first or third party library
+" names being imported incorrectly.
+function! ale_linters#python#pylsp#GetCwd(buffer) abort
+    let l:fake_linter = {
+    \   'name': 'pylsp',
+    \   'project_root': function('ale#python#FindProjectRoot'),
+    \}
+    let l:root = ale#lsp_linter#FindProjectRoot(a:buffer, l:fake_linter)
+
+    return !empty(l:root) ? l:root : v:null
+endfunction
+
 function! ale_linters#python#pylsp#GetCommand(buffer) abort
     let l:executable = ale_linters#python#pylsp#GetExecutable(a:buffer)
 
@@ -36,6 +49,7 @@ call ale#linter#Define('python', {
 \   'name': 'pylsp',
 \   'lsp': 'stdio',
 \   'executable': function('ale_linters#python#pylsp#GetExecutable'),
+\   'cwd': function('ale_linters#python#pylsp#GetCwd'),
 \   'command': function('ale_linters#python#pylsp#GetCommand'),
 \   'project_root': function('ale#python#FindProjectRoot'),
 \   'completion_filter': 'ale#completion#python#CompletionItemFilter',

ale_linters/python/pyright.vim

@@ -32,10 +32,24 @@ function! ale_linters#python#pyright#GetConfig(buffer) abort
     return l:config
 endfunction
 
+" Force the cwd of the server to be the same as the project root to
+" fix issues with treating local files matching first or third party library
+" names being imported incorrectly.
+function! ale_linters#python#pyright#GetCwd(buffer) abort
+    let l:fake_linter = {
+    \   'name': 'pyright',
+    \   'project_root': function('ale#python#FindProjectRoot'),
+    \}
+    let l:root = ale#lsp_linter#FindProjectRoot(a:buffer, l:fake_linter)
+
+    return !empty(l:root) ? l:root : v:null
+endfunction
+
 call ale#linter#Define('python', {
 \   'name': 'pyright',
 \   'lsp': 'stdio',
 \   'executable': {b -> ale#Var(b, 'python_pyright_executable')},
+\   'cwd': function('ale_linters#python#pyright#GetCwd'),
 \   'command': '%e --stdio',
 \   'project_root': function('ale#python#FindProjectRoot'),
 \   'completion_filter': 'ale#completion#python#CompletionItemFilter',

test/linter/test_pylsp.vader

@@ -10,6 +10,8 @@ After:
   call ale#assert#TearDownLinterTest()
 
 Execute(The pylsp command callback should return default string):
+  call ale#test#SetFilename('./foo.py')
+
   AssertLinter 'pylsp', ale#Escape('pylsp')
 
 Execute(The pylsp executable should be configurable):
@@ -22,6 +24,12 @@ Execute(The pylsp command callback should let you set options):
 
   AssertLinter 'pylsp', ale#Escape('pylsp') . ' --some-option'
 
+Execute(The cwd and project root should be detected correctly):
+  call ale#test#SetFilename('../test-files/python/with_virtualenv/subdir/foo/bar.py')
+
+  AssertLinterCwd ale#test#GetFilename('../test-files/python/with_virtualenv/subdir')
+  AssertLSPProject ale#test#GetFilename('../test-files/python/with_virtualenv/subdir')
+
 Execute(The pylsp executable should be run from the virtualenv path):
   call ale#test#SetFilename('../test-files/python/with_virtualenv/subdir/foo/bar.py')
 

test/linter/test_pyre.vader

@@ -8,6 +8,8 @@ After:
   call ale#assert#TearDownLinterTest()
 
 Execute(The pyre command callback should return default string):
+  call ale#test#SetFilename('./foo.py')
+
   AssertLinter 'pyre',  ale#Escape('pyre') . ' persistent'
 
 Execute(The pyre executable should be configurable):

test/linter/test_pyright.vader

@@ -10,6 +10,8 @@ After:
   call ale#assert#TearDownLinterTest()
 
 Execute(The command callback should return the correct default string):
+  call ale#test#SetFilename('./foo.py')
+
   AssertLinter
   \ 'pyright-langserver',
   \ ale#Escape('pyright-langserver') . ' --stdio'
@@ -30,6 +32,12 @@ Execute(The default configuration should be mostly empty):
 
   AssertLSPConfig {'python': {}}
 
+Execute(The cwd and project root should be detected correctly):
+  call ale#test#SetFilename('../test-files/python/with_virtualenv/subdir/foo/bar.py')
+
+  AssertLinterCwd ale#test#GetFilename('../test-files/python/with_virtualenv/subdir')
+  AssertLSPProject ale#test#GetFilename('../test-files/python/with_virtualenv/subdir')
+
 Execute(virtualenv paths should be set in configuration by default):
   call ale#test#SetFilename('../test-files/python/with_virtualenv/subdir/foo/bar.py')