ENH: prepend the editable project directory to sys.path

Signed-off-by: Filipe Laíns <[email protected]>

Author: FFY00

mesonpy/_editable.py

@@ -49,6 +49,14 @@ def find_spec(
         # if it's one of our modules, trigger a rebuild
         if fullname.split('.', maxsplit=1)[0] in self._top_level_modules:
             self.rebuild()
+            # prepend the project path to sys.path, so that the normal finder
+            # can find our modules
+            # we prepend so that our path comes before the current path (if
+            # the interpreter is run with -m), see gh-239
+            if sys.path[0] != self._project_path:
+                if self._project_path in sys.path:
+                    sys.path.remove(self._project_path)
+                sys.path.insert(0, self._project_path)
         # return none (meaning we "didn't find" the module) and let the normal
         # finders find/import it
         return None
@@ -65,6 +73,6 @@ def install(
             # prepend our finder to sys.meta_path, so that it is queried before
             # the normal finders, and can trigger a project rebuild
             sys.meta_path.insert(0, finder)
-            # add the project path to sys.path, so that the normal finder can
-            # find our modules
-            sys.path.append(project_path)
+            # we add the project path to sys.path later, so that we can prepend
+            # after the current directory is prepended (when -m is used)
+            # see gh-239