decoder: allow objects in for_each (#333)

decoder/body_extensions_test.go

@@ -667,7 +667,7 @@ func TestCompletionAtPos_BodySchema_Extensions_ForEach(t *testing.T) {
 					Value: "A meta-argument that accepts a map or a set of strings, and creates an instance for each item in that map or set.\n\n**Note**: A given block cannot use both `count` and `for_each`.",
 					Kind:  lang.MarkdownKind,
 				},
-				Detail: "optional, map of any single type or set of string",
+				Detail: "optional, map of any single type or set of string or object",
 				TextEdit: lang.TextEdit{
 					Range: hcl.Range{
 						Filename: "test.tf",
@@ -1102,6 +1102,20 @@ for_each =
 					},
 					Kind: lang.SetCandidateKind,
 				},
+				{
+					Label:  "{  }",
+					Detail: "object",
+					TextEdit: lang.TextEdit{
+						Range: hcl.Range{
+							Filename: "test.tf",
+							Start:    hcl.Pos{Line: 2, Column: 12, Byte: 43},
+							End:      hcl.Pos{Line: 2, Column: 12, Byte: 43},
+						},
+						NewText: "{\n}",
+						Snippet: "{\n}",
+					},
+					Kind: lang.ObjectCandidateKind,
+				},
 			}),
 		},
 	}

decoder/hover_test.go

@@ -1147,7 +1147,7 @@ func TestDecoder_HoverAtPos_extension_for_each(t *testing.T) {
 			hcl.Pos{Line: 2, Column: 5, Byte: 26},
 			&lang.HoverData{
 				Content: lang.MarkupContent{
-					Value: "**for_each** _optional, map of any single type or set of string_\n\n" +
+					Value: "**for_each** _optional, map of any single type or set of string or object_\n\n" +
 						"A meta-argument that accepts a map or a set of strings, and creates an instance for each item in that map or set.\n\n" +
 						"**Note**: A given block cannot use both `count` and `for_each`.",
 					Kind: lang.MarkdownKind,

decoder/internal/schemahelper/attribute_extensions.go

@@ -24,6 +24,12 @@ func ForEachAttributeSchema() *schema.AttributeSchema {
 		Constraint: schema.OneOf{
 			schema.AnyExpression{OfType: cty.Map(cty.DynamicPseudoType)},
 			schema.AnyExpression{OfType: cty.Set(cty.String)},
+			// Objects are still supported for backwards-compatible reasons
+			// but in general should be avoided here. We add it here because
+			// otherwise valid configuration would be flagged as invalid.
+			// We cannot suppress it in completion (yet) or otherwise inform
+			// the user of this anti-pattern though.
+			schema.AnyExpression{OfType: cty.EmptyObject},
 		},
 		Description: lang.Markdown("A meta-argument that accepts a map or a set of strings, and creates an instance for each item in that map or set.\n\n" +
 			"**Note**: A given block cannot use both `count` and `for_each`."),