feat: add task location data to json output (#1056)

* feat: add task location data to json output

* feat: add root taskfile location to --json output

taskfile/tasks.go

@@ -0,0 +1,45 @@
+package taskfile
+
+import (
+	"fmt"
+
+	"gopkg.in/yaml.v3"
+)
+
+// Tasks represents a group of tasks
+type Tasks map[string]*Task
+
+func (t *Tasks) UnmarshalYAML(node *yaml.Node) error {
+	switch node.Kind {
+	case yaml.MappingNode:
+		tasks := map[string]*Task{}
+		if err := node.Decode(tasks); err != nil {
+			return err
+		}
+
+		for name := range tasks {
+			// Set the task's name
+			if tasks[name] == nil {
+				tasks[name] = &Task{
+					Task: name,
+				}
+			}
+			tasks[name].Task = name
+
+			// Set the task's location
+			for _, keys := range node.Content {
+				if keys.Value == name {
+					tasks[name].Location = &Location{
+						Line:   keys.Line,
+						Column: keys.Column,
+					}
+				}
+			}
+		}
+
+		*t = Tasks(tasks)
+		return nil
+	}
+
+	return fmt.Errorf("yaml: line %d: cannot unmarshal %s into tasks", node.Line, node.ShortTag())
+}