Notify swiftly is unlinked when performing use, install and update

Author: plemarquand

Sources/Swiftly/Install.swift

@@ -82,7 +82,8 @@ struct Install: SwiftlyCommand {
     }
 
     mutating func run(_ ctx: SwiftlyCoreContext) async throws {
-        try await validatedConfig(ctx)
+        try await validateConfig(ctx)
+        try await valitateLinked(ctx)
 
         var config = try await Config.load(ctx)
         let toolchainVersion = try await Self.determineToolchainVersion(ctx, version: self.version, config: &config)

Sources/Swiftly/Link.swift

@@ -39,10 +39,14 @@ struct Link: SwiftlyCommand {
 
         if pathChanged {
             await ctx.print("""
-            Linked swiftly to \(toolchainVersion.name).
+            Linked swiftly to Swift \(toolchainVersion.name).
 
             \(Messages.refreshShell)
             """)
+        } else {
+            await ctx.print("""
+            Swiftly is already linked to Swift \(toolchainVersion.name).
+            """)
         }
     }
 }

Sources/Swiftly/SelfUpdate.swift

@@ -21,7 +21,7 @@ struct SelfUpdate: SwiftlyCommand {
     }
 
     mutating func run(_ ctx: SwiftlyCoreContext) async throws {
-        try await validatedConfig(ctx)
+        try await validateConfig(ctx)
 
         let swiftlyBin = Swiftly.currentPlatform.swiftlyBinDir(ctx) / "swiftly"
         guard try await fs.exists(atPath: swiftlyBin) else {

Sources/Swiftly/Swiftly.swift

@@ -95,8 +95,7 @@ extension Data {
 }
 
 extension SwiftlyCommand {
-    @discardableResult
-    public mutating func validatedConfig(_ ctx: SwiftlyCoreContext) async throws -> Config {
+    func validatedConfig(_ ctx: SwiftlyCoreContext) async throws -> Config {
         for requiredDir in Swiftly.requiredDirectories(ctx) {
             guard try await fs.exists(atPath: requiredDir) else {
                 do {
@@ -111,4 +110,9 @@ extension SwiftlyCommand {
         // Verifies that the configuration exists and can be loaded
         return try await Config.load(ctx)
     }
+
+    // Perform the verification done in `validatedConfig` without returning it.
+    func validateConfig(_ ctx: SwiftlyCoreContext) async throws {
+        let _ = try await validatedConfig(ctx)
+    }
 }

Sources/Swiftly/Unlink.swift

@@ -26,28 +26,17 @@ struct Unlink: SwiftlyCommand {
     }
 
     mutating func run(_ ctx: SwiftlyCoreContext) async throws {
-        try await validatedConfig(ctx)
+        try await validateConfig(ctx)
 
         var pathChanged = false
-        if let proxyTo = try? await Swiftly.currentPlatform.findSwiftlyBin(ctx) {
-            let swiftlyBinDir = Swiftly.currentPlatform.swiftlyBinDir(ctx)
-            let swiftlyBinDirContents = (try? await fs.ls(atPath: swiftlyBinDir)) ?? [String]()
-
-            var existingProxies = [String]()
-            for bin in swiftlyBinDirContents {
-                let linkTarget = try? await fs.readlink(atPath: swiftlyBinDir / bin)
-                if linkTarget == proxyTo {
-                    existingProxies.append(bin)
-                }
-            }
+        let existingProxies = try await symlinkedProxies(ctx)
 
-            for p in existingProxies {
-                let proxy = Swiftly.currentPlatform.swiftlyBinDir(ctx) / p
+        for p in existingProxies {
+            let proxy = Swiftly.currentPlatform.swiftlyBinDir(ctx) / p
 
-                if try await fs.exists(atPath: proxy) {
-                    try await fs.remove(atPath: proxy)
-                    pathChanged = true
-                }
+            if try await fs.exists(atPath: proxy) {
+                try await fs.remove(atPath: proxy)
+                pathChanged = true
             }
         }
 
@@ -57,3 +46,27 @@ struct Unlink: SwiftlyCommand {
         }
     }
 }
+
+func symlinkedProxies(_ ctx: SwiftlyCoreContext) async throws -> [String] {
+    if let proxyTo = try? await Swiftly.currentPlatform.findSwiftlyBin(ctx) {
+        let swiftlyBinDir = Swiftly.currentPlatform.swiftlyBinDir(ctx)
+        let swiftlyBinDirContents = (try? await fs.ls(atPath: swiftlyBinDir)) ?? [String]()
+        var proxies = [String]()
+        for bin in swiftlyBinDirContents {
+            let linkTarget = try? await fs.readlink(atPath: swiftlyBinDir / bin)
+            if linkTarget == proxyTo {
+                proxies.append(bin)
+            }
+        }
+        return proxies
+    }
+    return []
+}
+
+extension SwiftlyCommand {
+    func valitateLinked(_ ctx: SwiftlyCoreContext) async throws {
+        if try await symlinkedProxies(ctx).isEmpty {
+            await ctx.print(Messages.currentlyUnlinked)
+        }
+    }
+}

Sources/Swiftly/Update.swift

@@ -84,6 +84,7 @@ struct Update: SwiftlyCommand {
 
     public mutating func run(_ ctx: SwiftlyCoreContext) async throws {
         var config = try await validatedConfig(ctx)
+        try await valitateLinked(ctx)
 
         guard let parameters = try await self.resolveUpdateParameters(ctx, &config) else {
             if let toolchain = self.toolchain {

Sources/Swiftly/Use.swift

@@ -62,6 +62,8 @@ struct Use: SwiftlyCommand {
     mutating func run(_ ctx: SwiftlyCoreContext) async throws {
         var config = try await validatedConfig(ctx)
 
+        try await valitateLinked(ctx)
+
         // This is the bare use command where we print the selected toolchain version (or the path to it)
         guard let toolchain = self.toolchain else {
             let (selectedVersion, result) = try await selectToolchain(ctx, config: &config, globalDefault: self.globalDefault)
@@ -108,6 +110,7 @@ struct Use: SwiftlyCommand {
         }
 
         try await Self.execute(ctx, toolchain, globalDefault: self.globalDefault, assumeYes: self.root.assumeYes, &config)
+
     }
 
     /// Use a toolchain. This method can modify and save the input config and also create/modify a `.swift-version` file.

Sources/SwiftlyCore/Messages.swift

@@ -10,10 +10,21 @@ public enum Messages {
     """
 
     public static let unlinkSuccess = """
-    Swiftly is now unlinked and will not manage the active toolchain until the following command is run:
+    Swiftly is now unlinked and will not manage the active toolchain until the following
+    command is run:
 
         $ swiftly link
 
+
+    """
+
+    public static let currentlyUnlinked = """
+    Swiftly is currently unlinked and will not manage the active toolchain. You can run
+    the following command to link swiftly to the active toolchain:
+
+        $ swiftly link
+
+
     """
 
     public static func postInstall(_ command: String) -> String {