update warning text to be more helpful

src/components/node.js

@@ -104,7 +104,7 @@ class Node extends React.Component {
       if (!IS_DEV || !Immutable.is(nextProps.node, this.props.node)) {
         return true
       } else {
-        warn('Encountered different references for identical node values in "shouldComponentUpdate". Check that you are preserving references for the following node:\n', nextProps.node.toJS())
+        warn('A new immutable Node instance was encountered with an identical structure to the previous instance. This is usually a mistake and can impact performance. Make sure to preserve immutable references when nothing has changed. The node in question was:', nextProps.node)
       }
     }
 

src/models/selection.js

@@ -325,7 +325,7 @@ class Selection extends new Record(DEFAULTS) {
 
     // If the anchor node isn't a text node, match it to one.
     if (anchorNode.kind != 'text') {
-      warn('Selection anchor is on a non text node, matching to leaf')
+      warn('The selection anchor was set to a Node that is not a Text node. This should not happen and can degrade performance. The node in question was:', anchorNode)
       let anchorText = anchorNode.getTextAtOffset(anchorOffset)
       let offset = anchorNode.getOffset(anchorText)
       anchorOffset = anchorOffset - offset
@@ -334,7 +334,7 @@ class Selection extends new Record(DEFAULTS) {
 
     // If the focus node isn't a text node, match it to one.
     if (focusNode.kind != 'text') {
-      warn('Selection focus is on a non text node, matching to leaf')
+      warn('The selection focus was set to a Node that is not a Text node. This should not happen and can degrade performance. The node in question was:', focusNode)
       let focusText = focusNode.getTextAtOffset(focusOffset)
       let offset = focusNode.getOffset(focusText)
       focusOffset = focusOffset - offset

src/transforms/apply-operation.js

@@ -350,12 +350,15 @@ function setNode(state, operation) {
   let { document } = state
   let node = document.assertPath(path)
 
-  // Deprecate using setNode for updating children, or keys
+  // Deprecate the ability to overwite a node's children.
   if (properties.nodes && properties.nodes != node.nodes) {
-    warn('Updating Node.nodes through setNode is not allowed. Use appropriate insertion and removal functions.')
+    warn('Updating a Node\'s `nodes` property via `setNode()` is not allowed. Use the appropriate insertion and removal operations instead. The opeartion in question was:', operation)
     delete properties.nodes
-  } else if (properties.key && properties.key != node.key) {
-    warn('Updating Node.key through setNode is not allowed. You should not have to update keys yourself.')
+  }
+
+  // Deprecate the ability to change a node's key.
+  if (properties.key && properties.key != node.key) {
+    warn('Updating a Node\'s `key` property via `setNode()` is not allowed. There should be no reason to do this. The opeartion in question was:', operation)
     delete properties.key
   }
 

src/transforms/normalize.js

@@ -102,7 +102,7 @@ export function normalizeSelection(transform) {
     !document.hasDescendant(selection.anchorKey) ||
     !document.hasDescendant(selection.focusKey)
   ) {
-    warn('The selection was invalid and reset to start of the document.')
+    warn('The selection was invalid and was reset to start of the document. The selection in question was:', selection)
 
     const firstText = document.getFirstText()
     selection = selection.merge({

src/utils/normalize.js

@@ -59,7 +59,7 @@ function inline(value) {
 function key(value) {
   if (typeOf(value) == 'string') return value
 
-  warn('Deprecation: Passing a node instead of a key to a method accepting a key can reduce performances')
+  warn('An object was passed to a Node method instead of a `key` string. This was previously supported, but is being deprecated because it can have a negative impact on performance. The object in question was:', value)
   if (value instanceof Block) return value.key
   if (value instanceof Document) return value.key
   if (value instanceof Inline) return value.key

src/utils/warn.js

@@ -5,15 +5,16 @@ import IS_DEV from '../constants/is-dev'
  * Log a development warning.
  *
  * @param {String} message
+ * @param {Any} ...args
  */
 
-function warning(message, ...more) {
+function warn(message, ...args) {
   if (!IS_DEV) {
     return
   }
 
   if (typeof console !== 'undefined') {
-    console.error(`Warning: ${message}`, ...more) // eslint-disable-line no-console
+    console.warn(`Warning: ${message}`, ...args) // eslint-disable-line no-console
   }
 
   try {
@@ -28,6 +29,8 @@ function warning(message, ...more) {
 
 /**
  * Export.
+ *
+ * @type {Function}
  */
 
-export default warning
+export default warn