AST: Name lookup shouldn't filter out static/instance methods from instance/static context

We do this in a more general way higher up in the constraint
solver. Filtering out methods in name lookup only hurts
diagnostics.

In fact I don't think this behavior was intentional at all,
since the code in question was originally written in 2013
before a lot of the more recent member lookup and diagnostic
code was added.

This does break source compatibility though, but in a minor
way. See the change to the CoreGraphics overlay. Again,
though, I think this was an accident and not intentional.

Author: slavapestov

lib/AST/NameLookup.cpp

@@ -556,15 +556,8 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
 
         SmallVector<ValueDecl *, 4> Lookup;
         DC->lookupQualified(ExtendedType, Name, options, TypeResolver, Lookup);
-        bool isMetatypeType = ExtendedType->is<AnyMetatypeType>();
         bool FoundAny = false;
         for (auto Result : Lookup) {
-          // If we're looking into an instance, skip static functions.
-          if (!isMetatypeType &&
-              isa<FuncDecl>(Result) &&
-              cast<FuncDecl>(Result)->isStatic())
-            continue;
-
           // Classify this declaration.
           FoundAny = true;
 
@@ -575,12 +568,6 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
             else
               Results.push_back(UnqualifiedLookupResult(MetaBaseDecl, Result));
             continue;
-          } else if (auto FD = dyn_cast<FuncDecl>(Result)) {
-            if (FD->isStatic() && !isMetatypeType)
-              continue;
-          } else if (isa<EnumElementDecl>(Result)) {
-            Results.push_back(UnqualifiedLookupResult(BaseDecl, Result));
-            continue;
           }
 
           Results.push_back(UnqualifiedLookupResult(BaseDecl, Result));

stdlib/public/SDK/CoreGraphics/CGFloat.swift.gyb

@@ -175,7 +175,7 @@ public struct CGFloat {
   }
 
   public var magnitude: CGFloat {
-    return CGFloat(abs(native))
+    return CGFloat(Swift.abs(native))
   }
 
   public mutating func negate() {

test/expr/primary/unqualified_name.swift

@@ -28,6 +28,13 @@ struct S0 {
     _ = self.f0(:y:z:) // expected-error{{an empty argument label is spelled with '_'}}{{17-17=_}}
     _ = self.f1(_:`while`:) // expected-warning{{keyword 'while' does not need to be escaped in argument list}}{{19-20=}}{{25-26=}}
     _ = self.f2(_:`let`:)
+
+    _ = f3(_:y:z:) // expected-error{{static member 'f3(_:y:z:)' cannot be used on instance of type 'S0'}}
+  }
+
+  static func testStaticS0() {
+    _ = f0(_:y:z:)
+    _ = f3(_:y:z:)
   }
 
   static func f3(_ x: Int, y: Int, z: Int) -> S0 { return S0() }

test/expr/unary/selector/property.swift

@@ -37,7 +37,7 @@ class ObjCClass {
     let _ = #selector(setter: myConstant) // expected-error {{argument of '#selector(setter:)' refers to non-settable let 'myConstant'}}
     let _ = #selector(setter: myComputedReadOnlyProperty) // expected-error {{argument of '#selector(setter:)' refers to non-settable var 'myComputedReadOnlyProperty'}}
 
-    let _ = #selector(myClassFunc) // expected-error{{use of unresolved identifier 'myClassFunc'}}
+    let _ = #selector(myClassFunc) // expected-error{{static member 'myClassFunc' cannot be used on instance of type 'ObjCClass'}}
   }
 
   class func classMethod() {
@@ -173,7 +173,7 @@ class InstanceStaticTestClass {
 
   @objc static func staticMethod() {}
 
-  @objc func instanceMethod() {} // expected-note {{did you mean 'instanceMethod'?}}
+  @objc func instanceMethod() {}
 
   @objc func instanceAndStaticMethod() {}
   @objc class func instanceAndStaticMethod() {}
@@ -205,8 +205,8 @@ class InstanceStaticTestClass {
     let _ = #selector(instanceMethod)
 
     let _ = #selector(getter: staticProperty) // expected-error{{static member 'staticProperty' cannot be used on instance of type 'InstanceStaticTestClass'}}
-    let _ = #selector(classMethod) // expected-error{{use of unresolved identifier 'classMethod'}}
-    let _ = #selector(staticMethod) // expected-error{{use of unresolved identifier 'staticMethod'}}
+    let _ = #selector(classMethod) // expected-error{{static member 'classMethod' cannot be used on instance of type 'InstanceStaticTestClass'}}
+    let _ = #selector(staticMethod) // expected-error{{static member 'staticMethod' cannot be used on instance of type 'InstanceStaticTestClass'}}
 
     let _ = #selector(instanceAndStaticMethod)
   }