From 8832ea06667fdf353e3df6733aeddf873c7a6d6a Mon Sep 17 00:00:00 2001
From: Alexander Skvortsov <38059171+askvortsov1@users.noreply.github.com>
Date: Thu, 24 Sep 2020 22:30:55 -0400
Subject: [PATCH] Add in BC layer for props, initProps, m.withAttr, and m.prop
 (#2310)

---
 framework/core/js/src/common/Component.ts     | 32 ++++++++++++++++++-
 .../core/js/src/common/utils/patchMithril.js  |  7 ++++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/framework/core/js/src/common/Component.ts b/framework/core/js/src/common/Component.ts
index 605ae69fe..85386c7b6 100644
--- a/framework/core/js/src/common/Component.ts
+++ b/framework/core/js/src/common/Component.ts
@@ -132,5 +132,35 @@ export default abstract class Component<T extends ComponentAttrs = any> implemen
    *
    * This can be used to assign default values for missing, optional attrs.
    */
-  protected static initAttrs<T>(attrs: T): void {}
+  protected static initAttrs<T>(attrs: T): void {
+    // Deprecated, part of Mithril 2 BC layer
+    this.initProps(attrs);
+  }
+
+  // BEGIN DEPRECATED MITHRIL 2 BC LAYER
+
+  /**
+   * Initialize the component's attrs.
+   *
+   * This can be used to assign default values for missing, optional attrs.
+   *
+   * @deprecated, use initAttrs instead.
+   */
+  protected static initProps<T>(attrs: T): void {}
+
+  /**
+   * The attributes passed into the component.
+   *
+   * @see https://mithril.js.org/components.html#passing-data-to-components
+   *
+   * @deprecated, use attrs instead.
+   */
+  get props() {
+    return this.attrs;
+  }
+  set props(props) {
+    this.attrs = props;
+  }
+
+  // END DEPRECATED MITHRIL 2 BC LAYER
 }
diff --git a/framework/core/js/src/common/utils/patchMithril.js b/framework/core/js/src/common/utils/patchMithril.js
index 7f0c595d0..bea9cf30f 100644
--- a/framework/core/js/src/common/utils/patchMithril.js
+++ b/framework/core/js/src/common/utils/patchMithril.js
@@ -1,5 +1,6 @@
 import Stream from 'mithril/stream';
 import extract from './extract';
+import withAttr from './withAttr';
 
 export default function patchMithril(global) {
   const defaultMithril = global.m;
@@ -68,5 +69,11 @@ export default function patchMithril(global) {
 
   modifiedMithril.route.Link = modifiedLink;
 
+  // BEGIN DEPRECATED MITHRIL 2 BC LAYER
+  modifiedMithril.prop = Stream;
+
+  modifiedMithril.withAttr = withAttr;
+  // END DEPRECATED MITHRIL 2 BC LAYER
+
   global.m = modifiedMithril;
 }