feat: add .KEY variable

docs/docs/experiments/any_variables.md

@@ -63,8 +63,7 @@ tasks:
 ```
 
 There are many more templating functions which can be used with the new types of
-variables. For a full list, see the
-[slim-sprig][slim-sprig] documentation.
+variables. For a full list, see the [slim-sprig][slim-sprig] documentation.
 
 ## Looping over variables
 
@@ -102,8 +101,10 @@ tasks:
         cmd: echo {{.ITEM}}
 ```
 
-This also works for maps. However, remember that maps are unordered, so the
-order in which the items are looped over is random:
+This also works for maps. When looping over a map we also make an additional
+`{{.KEY}}` variable availabe that holds the string value of the map key.
+Remember that maps are unordered, so the order in which the items are looped
+over is random:
 
 ```yaml
 version: 3
@@ -121,7 +122,7 @@ tasks:
     cmds:
       - for:
           var: MAP
-        cmd: echo {{.ITEM.SUBKEY}}
+        cmd: echo {{.KEY}} {{.ITEM.SUBKEY}}
 ```
 
 String splitting is still supported and remember that for simple cases, you have

testdata/vars/any/Taskfile.yml

@@ -89,7 +89,7 @@ tasks:
     cmds:
       - for:
           var: MAP
-        cmd: echo {{.ITEM}}
+        cmd: echo {{.KEY}} {{.ITEM}}
 
   for-multi-layer-map:
     vars:
@@ -103,4 +103,4 @@ tasks:
     cmds:
       - for:
           var: MAP
-        cmd: echo {{.ITEM.SUBKEY}}
+        cmd: echo {{.KEY}} {{.ITEM.SUBKEY}}

variables.go

@@ -6,7 +6,6 @@ import (
 	"strings"
 
 	"github.com/joho/godotenv"
-	"golang.org/x/exp/maps"
 
 	"github.com/go-task/task/v3/errors"
 	"github.com/go-task/task/v3/internal/execext"
@@ -134,6 +133,7 @@ func (e *Executor) compiledTask(call taskfile.Call, evaluateShVars bool) (*taskf
 				continue
 			}
 			if cmd.For != nil {
+				var keys []string
 				var list []any
 				// Get the list from the explicit for list
 				if cmd.For.List != nil && len(cmd.For.List) > 0 {
@@ -171,7 +171,10 @@ func (e *Executor) compiledTask(call taskfile.Call, evaluateShVars bool) (*taskf
 							case []any:
 								list = value
 							case map[string]any:
-								list = maps.Values(value)
+								for k, v := range value {
+									keys = append(keys, k)
+									list = append(list, v)
+								}
 							default:
 								return nil, errors.TaskfileInvalidError{
 									URI: origTask.Location.Taskfile,
@@ -189,10 +192,13 @@ func (e *Executor) compiledTask(call taskfile.Call, evaluateShVars bool) (*taskf
 					as = "ITEM"
 				}
 				// Create a new command for each item in the list
-				for _, loopValue := range list {
+				for i, loopValue := range list {
 					extra := map[string]any{
 						as: loopValue,
 					}
+					if len(keys) > 0 {
+						extra["KEY"] = keys[i]
+					}
 					new.Cmds = append(new.Cmds, &taskfile.Cmd{
 						Cmd:         r.ReplaceWithExtra(cmd.Cmd, extra),
 						Task:        r.ReplaceWithExtra(cmd.Task, extra),