Reference filtering (partial)

Author: MikhailArkhipov

src/Analysis/Engine/Impl/ModuleAnalysis.cs

@@ -237,7 +237,15 @@ public VariablesResult GetVariables(Expression expr, SourceLocation location, st
                     foreach (var defScope in scope.EnumerateTowardsGlobal
                         .Where(s => s.ContainsVariable(name.Name) && (s == scope || s.VisibleToChildren || IsFirstLineOfFunction(scope, s, location)))) {
                         var scopeVariables = GetVariablesInScope(name, defScope).Distinct();
-                        variables = variables.Union(scopeVariables);
+                        // Filter our definitions that are below the requested location (such as reassignments)
+                        var above = scopeVariables.Where(v => new SourceLocation(v.Location.StartLine, v.Location.StartColumn) <= location);
+                        variables = variables.Union(above);
+                        
+                        // Break at the first definition so we don't spill into global scope
+                        // for similarly named function parameters.
+                        if (scopeVariables.Any(v => v.Type == VariableType.Definition)) {
+                            break;
+                        }
                     }
                 }
             } else if (expr is MemberExpression member && !string.IsNullOrEmpty(member.Name)) {

src/Analysis/Engine/Test/AnalysisTest.cs

@@ -3132,23 +3132,28 @@ def g():
         print(a)
         assert isinstance(a, int)
         a = 200
+        print(a)
 ";
                 await server.SendDidOpenTextDocument(uri, text);
 
                 var references = await server.SendFindReferences(uri, 3, 15);
                 references.Should().OnlyHaveReferences(
                     (uri, (1, 6, 1, 7), ReferenceKind.Definition),
                     (uri, (3, 14, 3, 15), ReferenceKind.Reference),
-                    (uri, (4, 26, 4, 27), ReferenceKind.Reference),
-                    (uri, (5, 8, 5, 9), ReferenceKind.Definition)
+                    (uri, (4, 26, 4, 27), ReferenceKind.Reference)
                 );
 
                 references = await server.SendFindReferences(uri, 5, 9);
                 references.Should().OnlyHaveReferences(
                     (uri, (1, 6, 1, 7), ReferenceKind.Definition),
                     (uri, (3, 14, 3, 15), ReferenceKind.Reference),
-                    (uri, (4, 26, 4, 27), ReferenceKind.Reference),
-                    (uri, (5, 8, 5, 9), ReferenceKind.Definition)
+                    (uri, (4, 26, 4, 27), ReferenceKind.Reference)
+                );
+
+                references = await server.SendFindReferences(uri, 6, 15);
+                references.Should().OnlyHaveReferences(
+                    (uri, (5, 9, 5, 10), ReferenceKind.Definition),
+                    (uri, (6, 15, 6, 16), ReferenceKind.Reference)
                 );
             }
         }
@@ -4367,7 +4372,7 @@ def f(a, b, c=0):
                 var uri = await server.OpenDefaultDocumentAndGetUriAsync(code);
                 var signatures = await server.SendSignatureHelp(uri, 6, 2);
 
-                signatures.Should().OnlyHaveSignature("f(a: float, int, str, b: float, int, str, c: float, int, str=0)");
+                signatures.Should().OnlyHaveSignature("f(a, b, c: int=0)");
             }
         }