image ls: allow custom format in cli config

Setting a custom format in the cli cofig should still be supported,
and not produce an error when specifying "--tree". Specifyihg both
"--tree" and "--format" still produces an error, but we could consider
allowing "json" format in a future update.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/image/list.go

@@ -114,6 +114,16 @@ func runImages(ctx context.Context, dockerCLI command.Cli, options imagesOptions
 		}
 	}
 
+	format := options.format
+	if len(format) == 0 {
+		if len(dockerCLI.ConfigFile().ImagesFormat) > 0 && !options.quiet && !options.tree {
+			format = dockerCLI.ConfigFile().ImagesFormat
+			useTree = false
+		} else {
+			format = formatter.TableFormatKey
+		}
+	}
+
 	if useTree {
 		return runTree(ctx, dockerCLI, treeOptions{
 			images:   images,
@@ -123,15 +133,6 @@ func runImages(ctx context.Context, dockerCLI command.Cli, options imagesOptions
 		})
 	}
 
-	format := options.format
-	if len(format) == 0 {
-		if len(dockerCLI.ConfigFile().ImagesFormat) > 0 && !options.quiet {
-			format = dockerCLI.ConfigFile().ImagesFormat
-		} else {
-			format = formatter.TableFormatKey
-		}
-	}
-
 	imageCtx := formatter.ImageContext{
 		Context: formatter.Context{
 			Output: dockerCLI.Out(),

cli/command/image/testdata/list-command-success.format.golden

@@ -1 +0,0 @@
-IMAGE   ID             DISK USAGE   CONTENT SIZE   EXTRA