Merge pull request #9430 from github/redsun82/swift-unknown-location

Swift: add `UnknownLocation`

Author: MathiasVP

swift/extractor/SwiftExtractor.cpp

@@ -84,6 +84,15 @@ static void extractFile(const SwiftExtractorConfiguration& config,
   TrapOutput trap{trapStream};
   TrapArena arena{};
 
+  // TODO move default location emission elsewhere, possibly in a separate global trap file
+  auto unknownFileLabel = arena.allocateLabel<FileTag>();
+  // the following cannot conflict with actual files as those have an absolute path starting with /
+  trap.assignKey(unknownFileLabel, "unknown");
+  trap.emit(FilesTrap{unknownFileLabel});
+  auto unknownLocationLabel = arena.allocateLabel<LocationTag>();
+  trap.assignKey(unknownLocationLabel, "unknown");
+  trap.emit(LocationsTrap{unknownLocationLabel, unknownFileLabel});
+
   // In the case of emtpy files, the dispatcher is not called, but we still want to 'record' the
   // fact that the file was extracted
   // TODO: to be moved elsewhere

swift/ql/lib/codeql/swift/elements/Locatable.qll

@@ -1,4 +1,9 @@
-// generated by codegen/codegen.py, remove this comment if you wish to edit this file
 private import codeql.swift.generated.Locatable
 
-class Locatable extends LocatableBase { }
+class Locatable extends LocatableBase {
+  override Location getLocation() {
+    result = LocatableBase.super.getLocation()
+    or
+    not exists(LocatableBase.super.getLocation()) and result instanceof UnknownLocation
+  }
+}

swift/ql/lib/codeql/swift/elements/Location.qll

@@ -9,3 +9,7 @@ class Location extends LocationBase {
     ec = getEndColumn()
   }
 }
+
+class UnknownLocation extends Location {
+  UnknownLocation() { hasLocationInfo("", 0, 0, 0, 0) }
+}

swift/ql/test/extractor-tests/declarations/accessor.ql

@@ -12,7 +12,7 @@ predicate isKnownKind(AccessorDecl decl, string kind) {
 
 from AccessorDecl decl, string kind
 where
-  exists(decl.getLocation()) and
+  decl.getLocation().getFile().getName().matches("%swift/ql/test%") and
   (
     isKnownKind(decl, kind)
     or

swift/ql/test/extractor-tests/files/files.expected

@@ -1 +1,2 @@
+| file://:0:0:0:0 |  |
 | hello.swift:0:0:0:0 | hello.swift |