Merge pull request #339 from tayloraswift/diagnose-wrong-directory

QoL diagnostic when specifying the wrong package path

Author: tayloraswift

Package.resolved

@@ -286,6 +286,15 @@ extension SSGC.PackageBuild
             json: artifacts / "\(self.id.package).package.json",
             leaf: true)
 
+        //  SwiftPM will climb up the directory tree until it finds a `Package.swift` file.
+        //  It is trying to be helpful, but it will cause problems so we need to diagnose if
+        //  this is happening.
+        switch FilePath.Directory.init(manifest.root.path)
+        {
+        case self.root: break
+        case let other: throw SSGC.PackagePathError.init(computed: self.root, manifest: other)
+        }
+
         print("""
             Resolving dependencies for '\(self.id.package)' \
             (swift-tools-version: \(manifest.format))

Sources/SymbolGraphBuilder/Builds/SSGC.PackageBuild.swift

@@ -0,0 +1,20 @@
+import System
+
+extension SSGC
+{
+    struct PackagePathError:Error
+    {
+        let computed:FilePath.Directory
+        let manifest:FilePath.Directory
+    }
+}
+extension SSGC.PackagePathError:CustomStringConvertible
+{
+    var description:String
+    {
+        """
+        Attempting to build a package at '\(computed)' \
+        but the nearest manifest is located in '\(manifest)'
+        """
+    }
+}

Sources/SymbolGraphBuilder/Builds/SSGC.PackagePathError.swift

@@ -11,7 +11,7 @@ extension FilePath
         else if
             let current:FilePath.Directory = .current()
         {
-            return current.path.appending(self.components)
+            return current.path.appending(self.components).lexicallyNormalized()
         }
         else
         {