1 files changed, 47 insertions, 0 deletions
diff --git a/devtools/client/webconsole/components/Output/MessageIndent.js b/devtools/client/webconsole/components/Output/MessageIndent.js
new file mode 100644
index 0000000000..cb77c5ef8c
--- /dev/null
+++ b/devtools/client/webconsole/components/Output/MessageIndent.js
@@ -0,0 +1,47 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const dom = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+const INDENT_WIDTH = 12;
+
+// Store common indents so they can be used without recreating the element during render.
+const CONSTANT_INDENTS = [getIndentElement(1)];
+const IN_WARNING_GROUP_INDENT = getIndentElement(1, "warning-indent");
+
+function getIndentElement(indent, className) {
+  return dom.span({
+    className: `indent${className ? " " + className : ""}`,
+    style: {
+      width: indent * INDENT_WIDTH,
+    },
+  });
+}
+
+function MessageIndent(props) {
+  const { indent, inWarningGroup } = props;
+
+  if (inWarningGroup) {
+    return IN_WARNING_GROUP_INDENT;
+  }
+
+  if (!indent) {
+    return null;
+  }
+
+  return CONSTANT_INDENTS[indent] || getIndentElement(indent);
+}
+
+MessageIndent.propTypes = {
+  indent: PropTypes.number,
+  inWarningGroup: PropTypes.bool,
+};
+
+module.exports.MessageIndent = MessageIndent;
+
+// Exported so we can test it with unit tests.
+module.exports.INDENT_WIDTH = INDENT_WIDTH;