allow looking up types of identifiers

crates/ty_ide/src/goto.rs

@@ -334,15 +334,24 @@ impl GotoTarget<'_> {
                 let (_, ty) = ty_python_semantic::definitions_for_unary_op(model, expression)?;
                 ty
             }
-            // TODO: Support identifier targets
+            GotoTarget::PatternMatchRest(pattern) => {
-            GotoTarget::PatternMatchRest(_)
+                model.inferred_type_for_identifier(pattern.rest.as_ref()?)
-            | GotoTarget::PatternKeywordArgument(_)
+            }
-            | GotoTarget::PatternMatchStarName(_)
+            GotoTarget::PatternKeywordArgument(pattern) => {
-            | GotoTarget::PatternMatchAsName(_)
+                model.inferred_type_for_identifier(&pattern.attr)
-            | GotoTarget::TypeParamParamSpecName(_)
+            }
-            | GotoTarget::TypeParamTypeVarTupleName(_)
+            GotoTarget::PatternMatchStarName(pattern) => {
-            | GotoTarget::NonLocal { .. }
+                model.inferred_type_for_identifier(pattern.name.as_ref()?)
-            | GotoTarget::Globals { .. } => return None,
+            }
+            GotoTarget::PatternMatchAsName(pattern) => {
+                model.inferred_type_for_identifier(pattern.name.as_ref()?)
+            }
+            GotoTarget::NonLocal { identifier } => model.inferred_type_for_identifier(identifier),
+            GotoTarget::Globals { identifier } => model.inferred_type_for_identifier(identifier),
+            // These don't really... *have* a type?
+            GotoTarget::TypeParamParamSpecName(_) | GotoTarget::TypeParamTypeVarTupleName(_) => {
+                return None;
+            }
         };
 
         Some(ty)

crates/ty_ide/src/goto_type_definition.rs

@@ -975,7 +975,26 @@ mod tests {
             "#,
         );
 
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r#"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+         --> main.py:4:22
+          |
+        2 | def my_func(command: str):
+        3 |     match command.split():
+        4 |         case ["get", ab]:
+          |                      ^^
+        5 |             x = ab
+          |
+        "#);
     }
 
     #[test]
@@ -1003,7 +1022,26 @@ mod tests {
             "#,
         );
 
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r#"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+         --> main.py:4:23
+          |
+        2 | def my_func(command: str):
+        3 |     match command.split():
+        4 |         case ["get", *ab]:
+          |                       ^^
+        5 |             x = ab
+          |
+        "#);
     }
 
     #[test]
@@ -1031,7 +1069,26 @@ mod tests {
             "#,
         );
 
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r#"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+         --> main.py:4:37
+          |
+        2 | def my_func(command: str):
+        3 |     match command.split():
+        4 |         case ["get", ("a" | "b") as ab]:
+          |                                     ^^
+        5 |             x = ab
+          |
+        "#);
     }
 
     #[test]
@@ -1065,7 +1122,26 @@ mod tests {
             "#,
         );
 
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+          --> main.py:10:30
+           |
+         8 | def my_func(event: Click):
+         9 |     match event:
+        10 |         case Click(x, button=ab):
+           |                              ^^
+        11 |             x = ab
+           |
+        ");
     }
 
     #[test]
@@ -1143,7 +1219,26 @@ mod tests {
             "#,
         );
 
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+          --> main.py:10:23
+           |
+         8 | def my_func(event: Click):
+         9 |     match event:
+        10 |         case Click(x, button=ab):
+           |                       ^^^^^^
+        11 |             x = ab
+           |
+        ");
     }
 
     #[test]
@@ -1395,7 +1490,26 @@ def outer():
         );
 
         // Should find the variable declaration in the outer scope, not the nonlocal statement
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r#"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+         --> main.py:6:18
+          |
+        5 |     def inner():
+        6 |         nonlocal xy
+          |                  ^^
+        7 |         xy = "modified"
+        8 |         return x  # Should find the nonlocal x declaration in outer scope
+          |
+        "#);
     }
 
     #[test]
@@ -1447,7 +1561,26 @@ def function():
         );
 
         // Should find the global variable declaration, not the global statement
-        assert_snapshot!(test.goto_type_definition(), @"No goto target found");
+        assert_snapshot!(test.goto_type_definition(), @r#"
+        info[goto-type-definition]: Type definition
+          --> stdlib/ty_extensions.pyi:20:1
+           |
+        19 | # Types
+        20 | Unknown = object()
+           | ^^^^^^^
+        21 | AlwaysTruthy = object()
+        22 | AlwaysFalsy = object()
+           |
+        info: Source
+         --> main.py:5:12
+          |
+        4 | def function():
+        5 |     global global_var
+          |            ^^^^^^^^^^
+        6 |     global_var = "modified"
+        7 |     return global_var  # Should find the global variable declaration
+          |
+        "#);
     }
 
     #[test]

crates/ty_ide/src/hover.rs

@@ -1704,7 +1704,26 @@ def outer():
         );
 
         // Should find the variable declaration in the outer scope, not the nonlocal statement
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r#"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+         --> main.py:6:18
+          |
+        5 |     def inner():
+        6 |         nonlocal xy
+          |                  ^-
+          |                  ||
+          |                  |Cursor offset
+          |                  source
+        7 |         xy = "modified"
+        8 |         return x  # Should find the nonlocal x declaration in outer scope
+          |
+        "#);
     }
 
     #[test]
@@ -1756,7 +1775,26 @@ def function():
         );
 
         // Should find the global variable declaration, not the global statement
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r#"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+         --> main.py:5:12
+          |
+        4 | def function():
+        5 |     global global_var
+          |            ^^^^^^^-^^
+          |            |      |
+          |            |      Cursor offset
+          |            source
+        6 |     global_var = "modified"
+        7 |     return global_var  # Should find the global variable declaration
+          |
+        "#);
     }
 
     #[test]
@@ -1770,7 +1808,26 @@ def function():
             "#,
         );
 
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r#"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+         --> main.py:4:22
+          |
+        2 | def my_func(command: str):
+        3 |     match command.split():
+        4 |         case ["get", ab]:
+          |                      ^-
+          |                      ||
+          |                      |Cursor offset
+          |                      source
+        5 |             x = ab
+          |
+        "#);
     }
 
     #[test]
@@ -1816,7 +1873,26 @@ def function():
             "#,
         );
 
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r#"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+         --> main.py:4:23
+          |
+        2 | def my_func(command: str):
+        3 |     match command.split():
+        4 |         case ["get", *ab]:
+          |                       ^-
+          |                       ||
+          |                       |Cursor offset
+          |                       source
+        5 |             x = ab
+          |
+        "#);
     }
 
     #[test]
@@ -1862,7 +1938,26 @@ def function():
             "#,
         );
 
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r#"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+         --> main.py:4:37
+          |
+        2 | def my_func(command: str):
+        3 |     match command.split():
+        4 |         case ["get", ("a" | "b") as ab]:
+          |                                     ^-
+          |                                     ||
+          |                                     |Cursor offset
+          |                                     source
+        5 |             x = ab
+          |
+        "#);
     }
 
     #[test]
@@ -1914,7 +2009,26 @@ def function():
             "#,
         );
 
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+          --> main.py:10:30
+           |
+         8 | def my_func(event: Click):
+         9 |     match event:
+        10 |         case Click(x, button=ab):
+           |                              ^-
+           |                              ||
+           |                              |Cursor offset
+           |                              source
+        11 |             x = ab
+           |
+        ");
     }
 
     #[test]
@@ -2011,7 +2125,26 @@ def function():
             "#,
         );
 
-        assert_snapshot!(test.hover(), @"Hover provided no content");
+        assert_snapshot!(test.hover(), @r"
+        Unknown
+        ---------------------------------------------
+        ```python
+        Unknown
+        ```
+        ---------------------------------------------
+        info[hover]: Hovered content is
+          --> main.py:10:23
+           |
+         8 | def my_func(event: Click):
+         9 |     match event:
+        10 |         case Click(x, button=ab):
+           |                       ^^^-^^
+           |                       |  |
+           |                       |  Cursor offset
+           |                       source
+        11 |             x = ab
+           |
+        ");
     }
 
     #[test]

crates/ty_python_semantic/src/semantic_model.rs

@@ -1,6 +1,6 @@
 use ruff_db::files::{File, FilePath};
 use ruff_db::source::{line_index, source_text};
-use ruff_python_ast::{self as ast, ExprStringLiteral, ModExpression};
+use ruff_python_ast::{self as ast, ExprStringLiteral, Identifier, ModExpression};
 use ruff_python_ast::{Expr, ExprRef, HasNodeIndex, name::Name};
 use ruff_python_parser::Parsed;
 use ruff_source_file::LineIndex;
@@ -90,6 +90,19 @@ impl<'db> SemanticModel<'db> {
         members
     }
 
+    pub fn inferred_type_for_identifier(&self, identifier: &Identifier) -> Type<'db> {
+        // TODO(#1637): semantic tokens is making this crash even with
+        // `try_expr_ref_in_ast` guarding this, for now just use `try_expression_scope_id`.
+        // The problematic input is `x: "float` (with a dangling quote). I imagine the issue
+        // is we're too eagerly setting `is_string_annotation` in inference.
+        let Some(file_scope) = self.scope(identifier.into()) else {
+            return Type::unknown();
+        };
+        let scope = file_scope.to_scope_id(self.db, self.file);
+
+        infer_scope_types(self.db, scope).expression_type(identifier)
+    }
+
     /// Resolve the given import made in this file to a Type
     pub fn resolve_module_type(&self, module: Option<&str>, level: u32) -> Option<Type<'db>> {
         let module = self.resolve_module(module, level)?;