feat(rule): add checkImage option

Author: 0x6b

README.md

@@ -49,6 +49,9 @@ textlint --rule @textlint-rule/no-invalid-control-character README.md
 - `checkCode`: `boolean`
     - Default: `false`
     - Check code if it is `true`
+- `checkImage`: `boolean`
+    - Default: `false`
+    - Check image title and alt texts if it is `true`
 
 ```json
 {

src/textlint-rule-no-invalid-control-character.js

@@ -27,13 +27,16 @@ const DEFAULT_OPTION = {
     // Define allow char code like `\u0019`
     allow: [],
     // Check code if it is true
-    checkCode: false
+    checkCode: false,
+    // Check image title and alt text if it is true
+    checkImage: false
 };
 
 const reporter = (context, options = {}) => {
     const { Syntax, RuleError, getSource, fixer, report } = context;
     const allow = options.allow || DEFAULT_OPTION.allow;
     const checkCode = options.checkCode !== undefined ? options.checkCode : DEFAULT_OPTION.checkCode;
+    const checkImage = options.checkImage !== undefined ? options.checkImage : DEFAULT_OPTION.checkImage;
     const checkNode = node => {
         const text = getSource(node);
         // Ignore \r \n \t
@@ -70,6 +73,11 @@ const reporter = (context, options = {}) => {
             if (checkCode) {
                 checkNode(node);
             }
+        },
+        [Syntax.Image](node) {
+            if (checkImage) {
+                checkNode(node);
+            }
         }
     };
 };

test/textlint-rule-no-invalid-control-character-test.js

@@ -39,6 +39,29 @@ tester.run("textlint-rule-no-invalid-control-character", rule, {
             options: {
                 checkCode: false
             }
+        },
+        {
+            text: `![textlint logo\u0008](https://textlint.github.io/img/textlint-icon_256x256.png "logo\u0019")`,
+            options: {
+                checkImage: false
+            }
+        },
+        {
+            text: `![textlint logo\u0008](https://textlint.github.io/img/textlint-icon_256x256.png "logo\u0019")`,
+            options: {
+                checkImage: true,
+                allow: ["\u0008", "\u0019"]
+            },
+            errors: [
+                {
+                    message: "Found invalid control character(BACKSPACE \\u0008)",
+                    index: 15
+                },
+                {
+                    message: "Found invalid control character(END OF MEDIUM \\u0019)",
+                    index: 80
+                }
+            ]
         }
     ],
     invalid: [
@@ -79,6 +102,35 @@ var value = "\u0008"
                 }
             ]
         },
+        {
+            text: `![textlint logo\u0008](https://textlint.github.io/img/textlint-icon_256x256.png "logo\u0019")`,
+            options: {
+                checkImage: true
+            },
+            errors: [
+                {
+                    message: "Found invalid control character(BACKSPACE \\u0008)",
+                    index: 15
+                },
+                {
+                    message: "Found invalid control character(END OF MEDIUM \\u0019)",
+                    index: 80
+                }
+            ]
+        },
+        {
+            text: `![textlint logo\u0008](https://textlint.github.io/img/textlint-icon_256x256.png "logo\u0019")`,
+            options: {
+                checkImage: true,
+                allow: ["\u0019"]
+            },
+            errors: [
+                {
+                    message: "Found invalid control character(BACKSPACE \\u0008)",
+                    index: 15
+                }
+            ]
+        },
         ...invalid
     ]
 });