Print a friendly message if a tool is not available

See arduino#755

Author: cmaglie

Diff for: commands/debug/debug.go

@@ -185,7 +185,11 @@ func getCommandLine(req *dbg.DebugConfigReq, pm *packagemanager.PackageManager)
 	if requiredTools, err := pm.FindToolsRequiredForBoard(board); err == nil {
 		for _, requiredTool := range requiredTools {
 			logrus.WithField("tool", requiredTool).Info("Tool required for debug")
-			toolProperties.Merge(requiredTool.RuntimeProperties())
+			if requiredTool.IsInstalled() {
+				toolProperties.Merge(requiredTool.RuntimeProperties())
+			} else {
+				errStream.Write([]byte(fmt.Sprintf("Warning: tool '%s' is not installed. It might not be available for your OS.", requiredTool)))
+			}
 		}
 	}
 

Diff for: commands/upload/upload.go

@@ -193,7 +193,11 @@ func runProgramAction(pm *packagemanager.PackageManager,
 	if requiredTools, err := pm.FindToolsRequiredForBoard(board); err == nil {
 		for _, requiredTool := range requiredTools {
 			logrus.WithField("tool", requiredTool).Info("Tool required for upload")
-			uploadProperties.Merge(requiredTool.RuntimeProperties())
+			if requiredTool.IsInstalled() {
+				uploadProperties.Merge(requiredTool.RuntimeProperties())
+			} else {
+				errStream.Write([]byte(fmt.Sprintf("Warning: tool '%s' is not installed. It might not be available for your OS.", requiredTool)))
+			}
 		}
 	}