From 43eb51b15af364e789c758574bb0aa8618a229e6 Mon Sep 17 00:00:00 2001
From: Charlie Marsh <charlie.r.marsh@gmail.com>
Date: Wed, 26 Jul 2023 14:17:50 -0400
Subject: [PATCH] Handle relative

---
 crates/ruff/src/checkers/ast/mod.rs   | 15 ++++++++++----
 crates/ruff_python_ast/src/helpers.rs | 30 +++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/crates/ruff/src/checkers/ast/mod.rs b/crates/ruff/src/checkers/ast/mod.rs
index 9946f26aa8..3382bc5a4f 100644
--- a/crates/ruff/src/checkers/ast/mod.rs
+++ b/crates/ruff/src/checkers/ast/mod.rs
@@ -39,7 +39,9 @@ use ruff_text_size::{TextRange, TextSize};
 
 use ruff_diagnostics::{Diagnostic, IsolationLevel};
 use ruff_python_ast::all::{extract_all_names, DunderAllFlags};
-use ruff_python_ast::helpers::{extract_handled_exceptions, to_module_path};
+use ruff_python_ast::helpers::{
+    extract_handled_exceptions, from_relative_import, from_relative_import_parts, to_module_path,
+};
 use ruff_python_ast::identifier::Identifier;
 use ruff_python_ast::str::trailing_quote;
 use ruff_python_ast::visitor::{walk_except_handler, walk_pattern, Visitor};
@@ -397,11 +399,16 @@ where
                         // be "foo.bar". Given `from foo import bar as baz`, `name` would be "baz"
                         // and `qualified_name` would be "foo.bar".
                         let name = alias.asname.as_ref().unwrap_or(&alias.name);
+
                         let qualified_name =
                             helpers::format_import_from_member(level, module, &alias.name);
-                        let module = module.unwrap();
-                        let call_path: Box<[&str]> =
-                            module.split('.').chain(once(alias.name.as_str())).collect();
+                        let call_path = from_relative_import_parts(
+                            self.module_path.unwrap_or_default(),
+                            level,
+                            module,
+                            &alias.name,
+                        );
+                        let call_path: Box<[&str]> = call_path.into_boxed_slice();
                         self.add_binding(
                             name,
                             alias.identifier(),
diff --git a/crates/ruff_python_ast/src/helpers.rs b/crates/ruff_python_ast/src/helpers.rs
index 923c732699..6d048d82cf 100644
--- a/crates/ruff_python_ast/src/helpers.rs
+++ b/crates/ruff_python_ast/src/helpers.rs
@@ -894,6 +894,36 @@ pub fn from_relative_import<'a>(module: &'a [String], name: &'a str) -> CallPath
     call_path
 }
 
+pub fn from_relative_import_parts<'a>(
+    module_path: &'a [String],
+    level: Option<u32>,
+    module: Option<&'a str>,
+    member: &'a str,
+) -> CallPath<'a> {
+    let mut call_path: CallPath = SmallVec::with_capacity(module_path.len() + 1);
+
+    // Start with the module path.
+    call_path.extend(module_path.iter().map(String::as_str));
+
+    // Remove segments based on the number of dots.
+    for _ in 0..level.unwrap_or(0) {
+        if call_path.is_empty() {
+            return SmallVec::new();
+        }
+        call_path.pop();
+    }
+
+    // Add the remaining segments.
+    if let Some(module) = module {
+        call_path.extend(module.split('.'));
+    }
+
+    // Add the member.
+    call_path.push(member);
+
+    call_path
+}
+
 /// Given an imported module (based on its relative import level and module name), return the
 /// fully-qualified module path.
 pub fn resolve_imported_module_path<'a>(