Add config migration of paging section to pagers array

pkg/config/app_config.go

@@ -310,6 +310,11 @@ func computeMigratedConfig(path string, content []byte, changes *ChangesSet) ([]
 		return nil, false, fmt.Errorf("Couldn't migrate config file at `%s`: %w", path, err)
 	}
 
+	err = migratePagers(&rootNode, changes)
+	if err != nil {
+		return nil, false, fmt.Errorf("Couldn't migrate config file at `%s`: %w", path, err)
+	}
+
 	// Add more migrations here...
 
 	if reflect.DeepEqual(rootNode, originalCopy) {
@@ -469,6 +474,37 @@ func migrateAllBranchesLogCmd(rootNode *yaml.Node, changes *ChangesSet) error {
 	})
 }
 
+func migratePagers(rootNode *yaml.Node, changes *ChangesSet) error {
+	return yaml_utils.TransformNode(rootNode, []string{"git"}, func(gitNode *yaml.Node) error {
+		pagingKeyNode, pagingValueNode := yaml_utils.LookupKey(gitNode, "paging")
+		if pagingKeyNode == nil || pagingValueNode.Kind != yaml.MappingNode {
+			// If there's no "paging" section (or it's not an object), there's nothing to do
+			return nil
+		}
+
+		pagersKeyNode, _ := yaml_utils.LookupKey(gitNode, "pagers")
+		if pagersKeyNode != nil {
+			// Conversely, if there *is* already a "pagers" array, we also have nothing to do.
+			// This covers the case where the user keeps both the "paging" section and the "pagers"
+			// array for the sake of easier testing of old versions.
+			return nil
+		}
+
+		pagingKeyNode.Value = "pagers"
+		pagingContentCopy := pagingValueNode.Content
+		pagingValueNode.Kind = yaml.SequenceNode
+		pagingValueNode.Tag = "!!seq"
+		pagingValueNode.Content = []*yaml.Node{{
+			Kind:    yaml.MappingNode,
+			Content: pagingContentCopy,
+		}}
+
+		changes.Add("Moved git.paging object to git.pagers array")
+
+		return nil
+	})
+}
+
 func (c *AppConfig) GetDebug() bool {
 	return c.debug
 }