check boolean value of infer_variance kwarg, too

Author: carljm

crates/ty_python_semantic/resources/mdtest/diagnostics/legacy_typevars.md

@@ -97,10 +97,10 @@ from typing import TypeVar
 T = TypeVar("T", covariant=True, contravariant=True)
 ```
 
-## Variance parameters must be unambiguous
+## Boolean parameters must be unambiguous
 
 ```py
-from typing import TypeVar
+from typing_extensions import TypeVar
 
 def cond() -> bool:
     return True
@@ -110,6 +110,9 @@ T = TypeVar("T", covariant=cond())
 
 # error: [invalid-legacy-type-variable]
 U = TypeVar("U", contravariant=cond())
+
+# error: [invalid-legacy-type-variable]
+V = TypeVar("V", infer_variance=cond())
 ```
 
 ## Invalid keyword arguments

crates/ty_python_semantic/resources/mdtest/generics/legacy/variables.md

@@ -234,10 +234,10 @@ from typing import TypeVar
 T = TypeVar("T", covariant=True, contravariant=True)
 ```
 
-### Variance parameters must be unambiguous
+### Boolean parameters must be unambiguous
 
 ```py
-from typing import TypeVar
+from typing_extensions import TypeVar
 
 def cond() -> bool:
     return True
@@ -247,6 +247,9 @@ T = TypeVar("T", covariant=cond())
 
 # error: [invalid-legacy-type-variable]
 U = TypeVar("U", contravariant=cond())
+
+# error: [invalid-legacy-type-variable]
+V = TypeVar("V", infer_variance=cond())
 ```
 
 ### Invalid keyword arguments

crates/ty_python_semantic/resources/mdtest/snapshots/legacy_typevars.md_-_Legacy_typevar_creat…_-_Variance_parameters_…_(3012e69bb401f693).snap renamed to crates/ty_python_semantic/resources/mdtest/snapshots/legacy_typevars.md_-_Legacy_typevar_creat…_-_Boolean_parameters_m…_(3edf97b20f58fa11).snap

@@ -3,7 +3,7 @@ source: crates/ty_test/src/lib.rs
 expression: snapshot
 ---
 ---
-mdtest name: legacy_typevars.md - Legacy typevar creation diagnostics - Variance parameters must be unambiguous
+mdtest name: legacy_typevars.md - Legacy typevar creation diagnostics - Boolean parameters must be unambiguous
 mdtest path: crates/ty_python_semantic/resources/mdtest/diagnostics/legacy_typevars.md
 ---
 
@@ -12,7 +12,7 @@ mdtest path: crates/ty_python_semantic/resources/mdtest/diagnostics/legacy_typev
 ## mdtest_snippet.py
 
 ```
- 1 | from typing import TypeVar
+ 1 | from typing_extensions import TypeVar
  2 | 
  3 | def cond() -> bool:
  4 |     return True
@@ -22,17 +22,20 @@ mdtest path: crates/ty_python_semantic/resources/mdtest/diagnostics/legacy_typev
  8 | 
  9 | # error: [invalid-legacy-type-variable]
 10 | U = TypeVar("U", contravariant=cond())
+11 | 
+12 | # error: [invalid-legacy-type-variable]
+13 | V = TypeVar("V", infer_variance=cond())
 ```
 
 # Diagnostics
 
 ```
 error[invalid-legacy-type-variable]: The `covariant` parameter of `TypeVar` cannot have an ambiguous truthiness
- --> src/mdtest_snippet.py:7:18
+ --> src/mdtest_snippet.py:7:28
   |
 6 | # error: [invalid-legacy-type-variable]
 7 | T = TypeVar("T", covariant=cond())
-  |                  ^^^^^^^^^^^^^^^^
+  |                            ^^^^^^
 8 |
 9 | # error: [invalid-legacy-type-variable]
   |
@@ -42,11 +45,25 @@ info: rule `invalid-legacy-type-variable` is enabled by default
 
 ```
 error[invalid-legacy-type-variable]: The `contravariant` parameter of `TypeVar` cannot have an ambiguous truthiness
-  --> src/mdtest_snippet.py:10:18
+  --> src/mdtest_snippet.py:10:32
    |
  9 | # error: [invalid-legacy-type-variable]
 10 | U = TypeVar("U", contravariant=cond())
-   |                  ^^^^^^^^^^^^^^^^^^^^
+   |                                ^^^^^^
+11 |
+12 | # error: [invalid-legacy-type-variable]
+   |
+info: rule `invalid-legacy-type-variable` is enabled by default
+
+```
+
+```
+error[invalid-legacy-type-variable]: The `infer_variance` parameter of `TypeVar` cannot have an ambiguous truthiness
+  --> src/mdtest_snippet.py:13:33
+   |
+12 | # error: [invalid-legacy-type-variable]
+13 | V = TypeVar("V", infer_variance=cond())
+   |                                 ^^^^^^
    |
 info: rule `invalid-legacy-type-variable` is enabled by default
 

crates/ty_python_semantic/src/types/infer/builder.rs

@@ -4134,7 +4134,7 @@ impl<'db, 'ast> TypeInferenceBuilder<'db, 'ast> {
                                 &self.context,
                                 "The `covariant` parameter of `TypeVar` \
                                 cannot have an ambiguous truthiness",
-                                kwarg,
+                                &kwarg.value,
                             );
                         }
                     }
@@ -4151,7 +4151,7 @@ impl<'db, 'ast> TypeInferenceBuilder<'db, 'ast> {
                                 &self.context,
                                 "The `contravariant` parameter of `TypeVar` \
                                 cannot have an ambiguous truthiness",
-                                kwarg,
+                                &kwarg.value,
                             );
                         }
                     }
@@ -4180,7 +4180,18 @@ impl<'db, 'ast> TypeInferenceBuilder<'db, 'ast> {
                         );
                     }
                     // TODO support `infer_variance` in legacy TypeVars
-                    self.infer_expression(&kwarg.value, TypeContext::default());
+                    if self
+                        .infer_expression(&kwarg.value, TypeContext::default())
+                        .bool(db)
+                        .is_ambiguous()
+                    {
+                        return error(
+                            &self.context,
+                            "The `infer_variance` parameter of `TypeVar` \
+                            cannot have an ambiguous truthiness",
+                            &kwarg.value,
+                        );
+                    }
                 }
                 name => {
                     // We don't return here; this error is informational since this will error