feat: support looping over map variables (#1436)

* feat: support looping over map variables

* feat: add .KEY variable

Author: pd93

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
 
@@ -86,8 +85,8 @@ tasks:
         cmd: echo {{.ITEM}}
 ```
 
-Because this experiment adds support for array variables, the `for` keyword has
-been updated to support looping over arrays directly:
+Because this experiment adds support for "collection-type" variables, the `for`
+keyword has been updated to support looping over arrays directly:
 
 ```yaml
 version: 3
@@ -102,6 +101,30 @@ tasks:
         cmd: echo {{.ITEM}}
 ```
 
+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
+
+tasks:
+  foo:
+    vars:
+      MAP:
+        KEY_1:
+          SUBKEY: sub_value_1
+        KEY_2:
+          SUBKEY: sub_value_2
+        KEY_3:
+          SUBKEY: sub_value_3
+    cmds:
+      - for:
+          var: MAP
+        cmd: echo {{.KEY}} {{.ITEM.SUBKEY}}
+```
+
 String splitting is still supported and remember that for simple cases, you have
 always been able to loop over an array without using variables at all:
 

testdata/vars/any/Taskfile.yml

@@ -9,6 +9,8 @@ tasks:
     - task: string-array
     - task: for-string
     - task: for-int
+    - task: for-map
+    - task: for-multi-layer-map
 
   dynamic:
     vars:
@@ -78,3 +80,27 @@ tasks:
           var: LIST
         cmd: echo {{add .ITEM 100}}
 
+  for-map:
+    vars:
+      MAP:
+        KEY_1: value_1
+        KEY_2: value_2
+        KEY_3: value_3
+    cmds:
+      - for:
+          var: MAP
+        cmd: echo {{.KEY}} {{.ITEM}}
+
+  for-multi-layer-map:
+    vars:
+      MAP:
+        KEY_1:
+          SUBKEY: sub_value_1
+        KEY_2:
+          SUBKEY: sub_value_2
+        KEY_3:
+          SUBKEY: sub_value_3
+    cmds:
+      - for:
+          var: MAP
+        cmd: echo {{.KEY}} {{.ITEM.SUBKEY}}

variables.go

@@ -133,6 +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 {
@@ -170,9 +171,9 @@ func (e *Executor) compiledTask(call taskfile.Call, evaluateShVars bool) (*taskf
 							case []any:
 								list = value
 							case map[string]any:
-								return &taskfile.Task{}, errors.TaskfileInvalidError{
-									URI: origTask.Location.Taskfile,
-									Err: errors.New("sh is not supported with the 'Any Variables' experiment enabled.\nSee https://taskfile.dev/experiments/any-variables for more information."),
+								for k, v := range value {
+									keys = append(keys, k)
+									list = append(list, v)
 								}
 							default:
 								return nil, errors.TaskfileInvalidError{
@@ -191,10 +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),