Disallow users from typing two spaces

@uberbryn I couldn't make it so we don't automatically type the space,
so I've just prevented users from double typing spaces in general.

Author: mxstbr

src/index.js

@@ -29,7 +29,7 @@ import insertText from "./modifiers/insertText";
 import changeCurrentBlockType from "./modifiers/changeCurrentBlockType";
 import createLinkDecorator from "./decorators/link";
 import createImageDecorator from "./decorators/image";
-import { replaceText } from "./utils";
+import { replaceText, getCurrentLine } from "./utils";
 import {
   CODE_BLOCK_REGEX,
   CODE_BLOCK_TYPE,
@@ -57,7 +57,7 @@ const defaultLanguages = {
   swift: "Swift",
 };
 
-const INLINE_STYLE_CHARACTERS = [" ", "*", "_"];
+const INLINE_STYLE_CHARACTERS = ["*", "_", "`", "~"];
 
 const defaultRenderSelect = ({ options, onChange, selectedValue }) => (
   <select value={selectedValue} onChange={onChange}>
@@ -347,6 +347,10 @@ const createMarkdownPlugin = (_config = {}) => {
       // If we're in a link - don't transform markdown
       if (inLink(editorState)) return "not-handled";
 
+      // Don't let users type two spaces after another
+      if (character === " " && getCurrentLine(editorState).slice(-1) === " ")
+        return "handled";
+
       const newEditorState = checkCharacterForState(
         config,
         editorState,

src/modifiers/handleInlineStyle.js

@@ -2,6 +2,7 @@ import changeCurrentInlineStyle from "./changeCurrentInlineStyle";
 import { EditorState, Modifier } from "draft-js";
 import { inlineMatchers } from "../constants";
 import insertText from "./insertText";
+import { getCurrentLine as getLine } from "../utils";
 
 const handleChange = (editorState, line, whitelist) => {
   let newEditorState = editorState;
@@ -27,32 +28,21 @@ const handleChange = (editorState, line, whitelist) => {
   return newEditorState;
 };
 
-const getLine = (editorState, anchorOffset) => {
-  const selection = editorState.getSelection().merge({ anchorOffset });
-  const key = editorState.getSelection().getStartKey();
-
-  return editorState
-    .getCurrentContent()
-    .getBlockForKey(key)
-    .getText()
-    .slice(0, selection.getFocusOffset());
-};
-
 const handleInlineStyle = (
   whitelist,
   editorStateWithoutCharacter,
   character
 ) => {
   const editorState = insertText(editorStateWithoutCharacter, character);
   let selection = editorState.getSelection();
-  let line = getLine(editorState, selection.getAnchorOffset());
+  let line = getLine(editorState);
   let newEditorState = handleChange(editorState, line, whitelist);
   let lastEditorState = editorState;
 
   // Recursively resolve markdown, e.g. _*text*_ should turn into both italic and bold
   while (newEditorState !== lastEditorState) {
     lastEditorState = newEditorState;
-    line = getLine(newEditorState, selection.getAnchorOffset());
+    line = getLine(newEditorState);
     newEditorState = handleChange(newEditorState, line, whitelist);
   }
 

src/modifiers/insertText.js

@@ -3,6 +3,7 @@ import { EditorState, Modifier } from "draft-js";
 const insertText = (editorState, text) => {
   const selection = editorState.getSelection();
   const content = editorState.getCurrentContent();
+  if (!selection.isCollapsed()) return editorState;
   const newContentState = Modifier.insertText(
     content,
     selection,

src/utils.js

@@ -1,5 +1,17 @@
 import { Modifier, EditorState } from "draft-js";
 
+export const getCurrentLine = editorState => {
+  const { anchorOffset } = editorState.getSelection();
+  const selection = editorState.getSelection().merge({ anchorOffset });
+  const key = editorState.getSelection().getStartKey();
+
+  return editorState
+    .getCurrentContent()
+    .getBlockForKey(key)
+    .getText()
+    .slice(0, selection.getFocusOffset());
+};
+
 export function addText(editorState, bufferText) {
   const contentState = Modifier.insertText(
     editorState.getCurrentContent(),