Merge pull request #60895 from LucianoPAlmeida/fix-magic-literal

[Sema] Fix dictionary duplicate keys false positives for #line and #column magic literal

Author: xedin

lib/Sema/MiscDiagnostics.cpp

@@ -5058,15 +5058,46 @@ diagnoseDictionaryLiteralDuplicateKeyEntries(const Expr *E,
 
   private:
     std::string getKeyStringValue(const LiteralExpr *keyExpr) {
-      if (isa<MagicIdentifierLiteralExpr>(keyExpr)) {
-        return keyExpr->getLiteralKindDescription().str();
+      if (auto *MLE = dyn_cast<MagicIdentifierLiteralExpr>(keyExpr)) {
+        return getMagicLiteralKeyValue(MLE);
       }
       std::string out;
       llvm::raw_string_ostream OS(out);
       keyExpr->printConstExprValue(&OS, /*additionalCheck=*/nullptr);
       return out;
     }
 
+    std::string getMagicLiteralKeyValue(const MagicIdentifierLiteralExpr *MLE) {
+      auto magicLiteralValue = MLE->getLiteralKindDescription().str();
+      switch (MLE->getKind()) {
+      case MagicIdentifierLiteralExpr::DSOHandle:
+      case MagicIdentifierLiteralExpr::FileID:
+      case MagicIdentifierLiteralExpr::FileIDSpelledAsFile:
+      case MagicIdentifierLiteralExpr::FilePath:
+      case MagicIdentifierLiteralExpr::FilePathSpelledAsFile:
+      case MagicIdentifierLiteralExpr::Function:
+        break;
+      // Those are literals that can evaluate to different values in a
+      // dictionary literal declaration context based on source position
+      // so we need to consider that position as part of the literal value.
+      case MagicIdentifierLiteralExpr::Column: {
+        unsigned int column;
+        std::tie(std::ignore, column) =
+            Ctx.SourceMgr.getPresumedLineAndColumnForLoc(MLE->getStartLoc());
+        magicLiteralValue += ":" + std::to_string(column);
+        break;
+      }
+      case MagicIdentifierLiteralExpr::Line: {
+        unsigned int line;
+        std::tie(line, std::ignore) =
+            Ctx.SourceMgr.getPresumedLineAndColumnForLoc(MLE->getStartLoc());
+        magicLiteralValue += ":" + std::to_string(line);
+        break;
+      }
+      }
+      return magicLiteralValue;
+    }
+
     std::string getKeyStringValueForDiagnostic(const LiteralExpr *keyExpr) {
       std::string out;
       switch (keyExpr->getKind()) {

test/Sema/diag_dictionary_keys_duplicated.swift

@@ -209,3 +209,21 @@ let _: [String: String] = [
   "\(a)": "B",
   "\(1)": "C"
 ]
+
+// https://github.com/apple/swift/issues/60873
+let _: [Int: String] = [
+  #line: "A",
+  #line: "B"
+]
+
+let _: [Int: String] = [#line: "A", #line: "B"] // expected-warning{{dictionary literal of type '[Int : String]' has duplicate entries for #line literal key}}
+// expected-note@-1{{duplicate key declared here}} {{25-35=}} {{35-36=}}
+// expected-note@-2{{duplicate key declared here}} {{37-47=}} {{35-36=}}
+
+let _: [Int: String] = [#column: "A", #column: "B"] // OK
+
+let _: [Int: String] = [
+  // expected-note@+1{{duplicate key declared here}} {{3-15=}} {{15-16=}} 
+  #column: "A", // expected-warning{{dictionary literal of type '[Int : String]' has duplicate entries for #column literal key}}
+  #column: "B"  // expected-note{{duplicate key declared here}} {{3-16=}} {{227:15-16=}}
+]