fix values that were narrowed to Never being coloured as a type

DetachHead · Jun 2, 2024 · e4e2c6d · e4e2c6d
1 parent 7972d3d
commit e4e2c6d
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Showing 3 changed files with 54 additions and 15 deletions.
diff --git a/packages/pyright-internal/src/analyzer/semanticTokensWalker.ts b/packages/pyright-internal/src/analyzer/semanticTokensWalker.ts
@@ -205,11 +205,19 @@ export class SemanticTokensWalker extends ParseTreeWalker {
                 }
         }
         const symbol = this._evaluator?.lookUpSymbolRecursive(node, node.value, false)?.symbol;
-        if (type?.category === TypeCategory.Never && symbol && !this._evaluator.getDeclaredTypeOfSymbol(symbol).type) {
-            // for some reason Never is considered both instantiable and an instance, so we need to look up the type this way
-            // to differentiate between "instances" of `Never` and type aliases/annotations of Never:
-            this._addItem(node.start, node.length, SemanticTokenTypes.type, []);
-            return;
+        if (type?.category === TypeCategory.Never && symbol) {
+            // for some reason Never is considered both instantiable and an instance, so we need a way
+            // to differentiate between "instances" of `Never` and type aliases/annotations of Never.
+            // this is probably extremely cringe since i have no idea what this is doing and i literally
+            // just brute forced random shit until all the tests passed
+            const typeResult = this._evaluator?.getEffectiveTypeOfSymbolForUsage(symbol, node);
+            if (
+                typeResult.type.category !== TypeCategory.Never &&
+                (typeResult.type.category !== TypeCategory.Unbound || !typeResult.includesIllegalTypeAliasDecl)
+            ) {
+                this._addItem(node.start, node.length, SemanticTokenTypes.type, []);
+                return;
+            }
         }
         const declarations = this._evaluator?.getDeclarationsForNameNode(node);
         if (declarations?.some(isParameterDeclaration)) {

diff --git a/packages/pyright-internal/src/tests/samples/semantic_highlighting/never.py b/packages/pyright-internal/src/tests/samples/semantic_highlighting/never.py
@@ -5,3 +5,15 @@
 
 def baz() -> Never:
     ...
+
+def asdf(foo: Never):
+    value: Never = foo
+    value
+
+Type = Never
+value: Type = 1
+
+def inferred():
+    value = ''
+    if not isinstance(value, str):
+        value
diff --git a/packages/pyright-internal/src/tests/semanticTokensProvider.test.ts b/packages/pyright-internal/src/tests/semanticTokensProvider.test.ts
@@ -51,16 +51,35 @@ if (process.platform !== 'win32' || !process.env['CI']) {
     test('never', () => {
         const result = semanticTokenizeSampleFile('never.py');
         expect(result).toStrictEqual([
-            { type: 'namespace', modifiers: [], start: 5, length: 6 },
-            { type: 'class', modifiers: [], start: 19, length: 5 },
-            { type: 'class', modifiers: [], start: 19, length: 5 },
-            { type: 'variable', modifiers: [], start: 26, length: 3 },
-            { type: 'type', modifiers: [], start: 31, length: 5 },
-            { type: 'class', modifiers: [], start: 37, length: 3 },
-            { type: 'class', modifiers: [], start: 43, length: 5 },
-            { type: 'function', modifiers: ['definition'], start: 54, length: 3 },
-            { type: 'function', modifiers: [], start: 54, length: 3 },
-            { type: 'type', modifiers: [], start: 63, length: 5 },
+            { type: 'namespace', modifiers: [], start: 5, length: 6 }, // typing
+            { type: 'class', modifiers: [], start: 19, length: 5 }, // Never
+            { type: 'class', modifiers: [], start: 19, length: 5 }, // Never
+            { type: 'variable', modifiers: [], start: 26, length: 3 }, // foo
+            { type: 'type', modifiers: [], start: 31, length: 5 }, // Never
+            { type: 'class', modifiers: [], start: 37, length: 3 }, // bar
+            { type: 'class', modifiers: [], start: 43, length: 5 }, // Never
+            { type: 'function', modifiers: ['definition'], start: 54, length: 3 }, // baz
+            { type: 'function', modifiers: [], start: 54, length: 3 }, // baz
+            { type: 'type', modifiers: [], start: 63, length: 5 }, // Never
+            { type: 'function', modifiers: ['definition'], start: 83, length: 4 }, // asdf
+            { type: 'function', modifiers: [], start: 83, length: 4 }, // asdf
+            { type: 'parameter', modifiers: ['definition'], start: 88, length: 3 }, // foo
+            { type: 'type', modifiers: [], start: 93, length: 5 }, // Never
+            { type: 'variable', modifiers: [], start: 105, length: 5 }, // value
+            { type: 'type', modifiers: [], start: 112, length: 5 }, // Never
+            { type: 'parameter', modifiers: [], start: 120, length: 3 }, // foo
+            { type: 'variable', modifiers: [], start: 128, length: 5 }, // value
+            { type: 'class', modifiers: [], start: 135, length: 4 }, // Type
+            { type: 'class', modifiers: [], start: 142, length: 5 }, // Never
+            { type: 'variable', modifiers: [], start: 148, length: 5 }, // value
+            { type: 'type', modifiers: [], start: 155, length: 4 }, // Type
+            { type: 'function', modifiers: ['definition'], start: 169, length: 8 }, // inferred
+            { type: 'function', modifiers: [], start: 169, length: 8 }, // inferred
+            { type: 'variable', modifiers: [], start: 185, length: 5 }, // value
+            { type: 'function', modifiers: ['defaultLibrary', 'builtin'], start: 207, length: 10 }, // isinstance
+            { type: 'variable', modifiers: [], start: 218, length: 5 }, // value
+            { type: 'class', modifiers: ['defaultLibrary', 'builtin'], start: 225, length: 3 }, // str
+            { type: 'variable', modifiers: [], start: 239, length: 5 }, // value
         ]);
     });