set project_root where the config file may be

linter.py

@@ -13,6 +13,7 @@
 
 from collections import defaultdict
 import hashlib
+from itertools import chain, takewhile
 import logging
 import os
 import shutil
@@ -32,12 +33,57 @@
     class TemporaryDirectory(Protocol):
         name = None  # type: str
 
+HOME = os.path.expanduser('~')
 
 USER = getpass.getuser()
 TMPDIR_PREFIX = "SublimeLinter-contrib-mypy-%s" % USER
 
 logger = logging.getLogger("SublimeLinter.plugin.mypy")
 
+
+def paths_upwards(path):
+    while True:
+        yield path
+
+        next_path = os.path.dirname(path)
+        # Stop just before root in *nix systems
+        if next_path == '/':
+            return
+
+        if next_path == path:
+            return
+
+        path = next_path
+
+
+def paths_upwards_until_home(path):
+    return chain(takewhile(lambda p: p != HOME, paths_upwards(path)), [HOME])
+
+
+def find_project_root(src):
+    """Attempt to get the project root."""
+    for src in paths_upwards_until_home(src):
+        if os.path.exists(os.path.join(src, "mypy.ini")):
+            return src
+
+        if os.path.exists(os.path.join(src, ".mypy.ini")):
+            return src
+
+        if os.path.exists(os.path.join(src, "pyproject.toml")):
+            return src
+
+        if os.path.exists(os.path.join(src, "setup.cfg")):
+            return src
+
+        if os.path.exists(os.path.join(src, ".git")):
+            return src
+
+        if os.path.exists(os.path.join(src, ".hg")):
+            return src
+
+    return src
+
+
 # Mapping for our created temporary directories.
 # For smarter caching purposes,
 # we index different cache folders based on the working dir.
@@ -115,6 +161,8 @@ def cmd(self):
 
                 self.settings.set('cache-dir', cache_dir)
 
+        self.context['project_root'] = find_project_root(self.view.file_name())
+
         return cmd
 
     def run(self, cmd, code):