avoid infinite loop, allow exiting with double-space

lib/camel-case-mode.js

@@ -11,6 +11,7 @@ export default {
   editor: null,
   editorView: null,
   capitalizeNextDisposable: null,
+  isCapitalizing: false,
 
   activate (state) {
     this.capitalizeNextDisposable = new CompositeDisposable()
@@ -39,24 +40,37 @@ export default {
 
   disable () {
     this.isEnabled = false
+    this.isCapitalizing = false
     this.capitalizeNextDisposable && this.capitalizeNextDisposable.dispose()
-    this.editorView.classList.remove(MODE_CLASS)
+    this.editorView && this.editorView.classList.remove(MODE_CLASS)
     this.editorView = null
   },
 
   toggle () {
-    console.log(this)
     return this.isEnabled
       ? this.disable()
       : this.enable()
   },
 
   capitalizeNext () {
-    this.capitalizeNextDisposable.add(this.editor.onWillInsertText(({text}) => {
-      if (text === ' ') {
-        return this.disable()
-      }
-      this.editor.insertText(text.toUpperCase())
-    }))
+    if (this.isCapitalizing) {
+      this.disable()
+      return this.editor.insertText(' ')
+    }
+
+    this.isCapitalizing = true
+
+    this.capitalizeNextDisposable = new CompositeDisposable(
+      this.editor.onWillInsertText(({text, cancel}) => {
+        if (!text || text.length !== 1) return
+        if (text === '\n') {
+          return this.disable()
+        }
+        cancel()
+        this.capitalizeNextDisposable.dispose()
+        this.editor.insertText(text.toUpperCase())
+        this.isCapitalizing = false
+      })
+    )
   }
 }