Check path permissions earlier during install

news/6762.bugfix

@@ -0,0 +1 @@
+Fail without collecting and downloading packages if user doesn't have write permissions.

src/pip/_internal/commands/install.py

@@ -240,6 +240,31 @@ def __init__(self, *args, **kw):
         self.parser.insert_option_group(0, cmd_opts)
 
     def run(self, options, args):
+        if (options.target_dir is not None and not
+                check_path_owner(options.target_dir)):
+            logger.error(
+                "The user that ran pip install doesn't have write access "
+                "to target directory '%s'",
+                options.target_dir,
+            )
+            return ERROR
+        if (options.prefix_path is not None and not
+                check_path_owner(options.prefix_path)):
+            logger.error(
+                "The user that ran pip install doesn't have write access "
+                "to target prefix directory '%s'",
+                options.prefix_path,
+            )
+            return ERROR
+        if (options.root_path is not None and not
+                check_path_owner(options.root_path)):
+            logger.error(
+                "The user that ran pip install doesn't have write access "
+                "to target root directory '%s'",
+                options.root_path,
+            )
+            return ERROR
+
         cmdoptions.check_install_build_global(options)
         upgrade_strategy = "to-satisfy-only"
         if options.upgrade: