[Diagnostics] Extract logic common to all key path invalid ref diagnostics

Author: xedin

lib/Sema/CSDiagnostics.cpp

@@ -2449,9 +2449,8 @@ bool KeyPathSubscriptIndexHashableFailure::diagnoseAsError() {
   return true;
 }
 
-bool InvalidStaticMemberRefInKeyPath::diagnoseAsError() {
+SourceLoc InvalidMemberRefInKeyPath::getLoc() const {
   auto *anchor = getRawAnchor();
-  auto loc = anchor->getLoc();
 
   if (auto *KPE = dyn_cast<KeyPathExpr>(anchor)) {
     auto *locator = getLocator();
@@ -2461,9 +2460,13 @@ bool InvalidStaticMemberRefInKeyPath::diagnoseAsError() {
         });
 
     assert(component != locator->getPath().end());
-    loc = KPE->getComponents()[component->getValue()].getLoc();
+    return KPE->getComponents()[component->getValue()].getLoc();
   }
 
-  emitDiagnostic(loc, diag::expr_keypath_static_member, Member->getBaseName());
+  return anchor->getLoc();
+}
+
+bool InvalidStaticMemberRefInKeyPath::diagnoseAsError() {
+  emitDiagnostic(getLoc(), diag::expr_keypath_static_member, getName());
   return true;
 }

lib/Sema/CSDiagnostics.h

@@ -1031,6 +1031,26 @@ class KeyPathSubscriptIndexHashableFailure final : public FailureDiagnostic {
   bool diagnoseAsError() override;
 };
 
+class InvalidMemberRefInKeyPath : public FailureDiagnostic {
+  ValueDecl *Member;
+
+public:
+  InvalidMemberRefInKeyPath(Expr *root, ConstraintSystem &cs, ValueDecl *member,
+                            ConstraintLocator *locator)
+      : FailureDiagnostic(root, cs, locator), Member(member) {
+    assert(member->hasName());
+    assert(locator->isForKeyPathComponent());
+  }
+
+  DeclName getName() const { return Member->getFullName(); }
+
+  bool diagnoseAsError() override = 0;
+
+protected:
+  /// Compute location of the failure for diagnostic.
+  SourceLoc getLoc() const;
+};
+
 /// Diagnose an attempt to reference a static member as a key path component
 /// e.g.
 ///
@@ -1041,16 +1061,11 @@ class KeyPathSubscriptIndexHashableFailure final : public FailureDiagnostic {
 ///
 /// _ = \S.Type.foo
 /// ```
-class InvalidStaticMemberRefInKeyPath final : public FailureDiagnostic {
-  ValueDecl *Member;
-
+class InvalidStaticMemberRefInKeyPath final : public InvalidMemberRefInKeyPath {
 public:
   InvalidStaticMemberRefInKeyPath(Expr *root, ConstraintSystem &cs,
                                   ValueDecl *member, ConstraintLocator *locator)
-      : FailureDiagnostic(root, cs, locator), Member(member) {
-    assert(member->hasName());
-    assert(locator->isForKeyPathComponent());
-  }
+      : InvalidMemberRefInKeyPath(root, cs, member, locator) {}
 
   bool diagnoseAsError() override;
 };