Fix missing check on one-line code-blocks

Closes GH-230.
Closes GH-233.

Reviewed-by: Christian Murphy <[email protected]>
Reviewed-by: Titus Wormer <[email protected]>

Author: AlexWayfer

packages/remark-lint-no-shell-dollars/index.js

@@ -10,6 +10,10 @@
  *
  * @example {"name": "ok.md"}
  *
+ *   ```bash
+ *   echo a
+ *   ```
+ *
  *   ```sh
  *   echo a
  *   echo a > file
@@ -34,14 +38,19 @@
  *
  * @example {"name": "not-ok.md", "label": "input"}
  *
+ *   ```sh
+ *   $ echo a
+ *   ```
+ *
  *   ```bash
  *   $ echo a
  *   $ echo a > file
  *   ```
  *
  * @example {"name": "not-ok.md", "label": "output"}
  *
- *   1:1-4:4: Do not use dollar signs before shell commands
+ *   1:1-3:4: Do not use dollar signs before shell commands
+ *   5:1-8:4: Do not use dollar signs before shell commands
  */
 
 'use strict'
@@ -81,11 +90,13 @@ function noShellDollars(tree, file) {
 
     // Check both known shell code and unknown code.
     if (!generated(node) && node.lang && flags.indexOf(node.lang) !== -1) {
-      lines = node.value.split('\n')
+      lines = node.value.split('\n').filter(function (line) {
+        return line
+      })
       length = lines.length
       index = -1
 
-      if (length <= 1) {
+      if (length === 0) {
         return
       }
 

packages/remark-lint-no-shell-dollars/readme.md

@@ -29,6 +29,10 @@ This rule is included in the following presets:
 ###### In
 
 ````markdown
+```bash
+echo a
+```
+
 ```sh
 echo a
 echo a > file
@@ -61,6 +65,10 @@ No messages.
 ###### In
 
 ````markdown
+```sh
+$ echo a
+```
+
 ```bash
 $ echo a
 $ echo a > file
@@ -70,7 +78,8 @@ $ echo a > file
 ###### Out
 
 ```text
-1:1-4:4: Do not use dollar signs before shell commands
+1:1-3:4: Do not use dollar signs before shell commands
+5:1-8:4: Do not use dollar signs before shell commands
 ```
 
 ## Install