Use Windows file paths for fake output paths

Author: ahoppen

Sources/SKTestSupport/CustomBuildServerTestProject.swift

@@ -135,6 +135,16 @@ package extension CustomBuildServer {
     )
   }
 
+  /// Returns a fake path that is unique to this target and file combination and can be used to identify this
+  /// combination in a unit's output path.
+  func fakeOutputPath(for file: String, in target: String) -> String {
+    #if os(Windows)
+    return #"C:\"# + target + #"\"# + file + ".o"
+    #else
+    return "/" + target + "/" + file + ".o"
+    #endif
+  }
+
   func sourceItem(for url: URL, outputPath: String) -> SourceItem {
     SourceItem(
       uri: URI(url),

Sources/SemanticIndex/CheckedIndex.swift

@@ -522,10 +522,8 @@ private struct IndexOutOfDateChecker {
       // updated.
       while let relativeSymlinkDestination = try? FileManager.default.destinationOfSymbolicLink(
         atPath: fileURL.filePath
-      ),
-        let symlinkDestination = URL(string: relativeSymlinkDestination, relativeTo: fileURL)
-      {
-        fileURL = symlinkDestination
+      ) {
+        fileURL = URL(fileURLWithPath: relativeSymlinkDestination, relativeTo: fileURL)
         modificationDate = max(modificationDate, try Self.modificationDate(atPath: fileURL.filePath))
       }
 

Tests/SourceKitLSPTests/BackgroundIndexingTests.swift

@@ -2185,15 +2185,27 @@ final class BackgroundIndexingTests: XCTestCase {
           SourcesItem(
             target: libATarget,
             sources: [
-              sourceItem(for: projectRoot.appendingPathComponent("Shared.swift"), outputPath: "/LibA/Shared.swift.o"),
-              sourceItem(for: projectRoot.appendingPathComponent("LibA.swift"), outputPath: "/LibA/LibA.swift.o"),
+              sourceItem(
+                for: projectRoot.appendingPathComponent("Shared.swift"),
+                outputPath: fakeOutputPath(for: "Shared.swift", in: "LibA")
+              ),
+              sourceItem(
+                for: projectRoot.appendingPathComponent("LibA.swift"),
+                outputPath: fakeOutputPath(for: "LibA.swift", in: "LibA")
+              ),
             ]
           ),
           SourcesItem(
             target: libBTarget,
             sources: [
-              sourceItem(for: projectRoot.appendingPathComponent("Shared.swift"), outputPath: "/LibB/Shared.swift.o"),
-              sourceItem(for: projectRoot.appendingPathComponent("LibB.swift"), outputPath: "/LibB/LibB.swift.o"),
+              sourceItem(
+                for: projectRoot.appendingPathComponent("Shared.swift"),
+                outputPath: fakeOutputPath(for: "Shared.swift", in: "LibB")
+              ),
+              sourceItem(
+                for: projectRoot.appendingPathComponent("LibB.swift"),
+                outputPath: fakeOutputPath(for: "LibB.swift", in: "LibB")
+              ),
             ]
           ),
         ]
@@ -2289,13 +2301,19 @@ final class BackgroundIndexingTests: XCTestCase {
           SourcesItem(
             target: libATarget,
             sources: [
-              sourceItem(for: projectRoot.appendingPathComponent("LibA.c"), outputPath: "/LibA/LibA.c.o")
+              sourceItem(
+                for: projectRoot.appendingPathComponent("LibA.c"),
+                outputPath: fakeOutputPath(for: "LibA.c", in: "LibA")
+              )
             ]
           ),
           SourcesItem(
             target: libBTarget,
             sources: [
-              sourceItem(for: projectRoot.appendingPathComponent("LibB.c"), outputPath: "/LibB/LibB.c.o")
+              sourceItem(
+                for: projectRoot.appendingPathComponent("LibB.c"),
+                outputPath: fakeOutputPath(for: "LibB.c", in: "LibB")
+              )
             ]
           ),
         ]