Add outdated command

README.md

@@ -94,6 +94,7 @@ Run `mint help` to see usage instructions.
 - **which**: Print the path to an installed package executable.
 - **uninstall**: Uninstalls a package by name.
 - **bootstrap**: Installs all the packages in your [Mintfile](#mintfile), by default, without linking them globally
+- **outdated**: List all in your [Mintfile](#mintfile), by default, installed and linked packages that are outdated.
 
 **Package reference**
 

Sources/MintCLI/Commands/OutdatedCommand.swift

@@ -0,0 +1,19 @@
+
+import Foundation
+import MintKit
+import PathKit
+import SwiftCLI
+
+class OutdatedCommand: MintfileCommand {
+
+    init(mint: Mint) {
+        super.init(mint: mint,
+                   name: "outdated",
+                   description: "List all the currently installed and linked packages that are outdated.")
+    }
+
+    override func execute() throws {
+        try super.execute()
+        try mint.outdated()
+    }
+}

Sources/MintCLI/MintCLI.swift

@@ -32,6 +32,7 @@ public class MintCLI {
             ListCommand(mint: mint),
             BootstrapCommand(mint: mint),
             WhichCommand(mint: mint),
+            OutdatedCommand(mint: mint),
         ])
     }
 

Sources/MintKit/Mint.swift

@@ -497,6 +497,46 @@ public class Mint {
         }
     }
 
+    public func outdated() throws {
+
+        let mintFile = try Mintfile(path: mintFilePath)
+
+        guard !mintFile.packages.isEmpty else {
+            standardOut <<< "🌱  Mintfile is empty"
+            return
+        }
+
+        let packageCount = "\(mintFile.packages.count) \(mintFile.packages.count == 1 ? "package" : "packages")"
+
+        if verbose {
+            output("Found \(packageCount) in \(mintFilePath.string)")
+        }
+
+        var hasUpdates = false
+        for package in mintFile.packages {
+
+            let tagOutput = try Task.capture(bash: "git ls-remote --tags --refs \(package.gitPath)")
+            let versions = tagOutput.stdout
+                .split(separator: "\n")
+                .map { String($0.split(separator: "\t").last!.split(separator: "/").last!) }
+                .compactMap { Version($0) }
+                .sorted()
+
+            if let latestVersion = versions.last,
+               let packageVersion = Version(package.version) {
+
+                if packageVersion < latestVersion {
+                    hasUpdates = true
+                    output("\(package.name) is outdated: \(packageVersion.description) -> \(latestVersion.description)".yellow)
+                }
+            }
+        }
+
+        if !hasUpdates {
+            output("\(packageCount) up to date".green)
+        }
+    }
+
     public func uninstall(name: String) throws {
 
         // find packages