docs(README): Update REAME

Author: azu

README.md

@@ -30,10 +30,96 @@ This rule check the spell by used with `prh.yml`.
 
 `textlint-rule-prh` support `--fix` feature of textlint.
 
-### What is prh.yml?
+```sh
+textlint --fix README.md
+```
+
+## What is prh.yml?
 
 Please See [vvakame/prh](https://github.com/vvakame/prh "vvakame/prh").
 
+### prh format
+
+`prh.yml` can define RegExp as a dictionary.
+
+```yaml
+# prh version
+version: 1
+rules:
+
+  # format case-sensitive
+  - expected: Cookie
+  # the above is equal to following
+  # - expected: Cookie
+  #   pattern: "/[CcＣｃ][OoＯｏ][OoＯｏ][KkＫｋ][IiＩｉ][EeＥｅ]/g"
+  #   options:
+  #     wordBoundary: false
+  #   specs: []
+
+  # Write test to `expect`
+  - expected: jQuery
+    specs:
+      - from: jquery
+        to:   jQuery
+      - from: ＪＱＵＥＲＹ
+        to:   jQuery
+
+# If the `specs` is failed、fail to load prh.yml
+# - expected: JavaScript
+#   specs:
+#     - from: JAVASCRIPT
+#       to:   JavaScprit
+# Error: JavaScript spec failed. "JAVASCRIPT", expected "JavaScprit", but got "JavaScript", /[JjＪｊ][AaＡａ][VvＶｖ][AaＡａ][SsＳｓ][CcＣｃ][RrＲｒ][IiＩｉ][PpＰｐ][TtＴｔ]/g
+
+# pattern => expected
+  - expected: default
+    pattern:  deflaut
+
+# Allow to write multiple `pattern`
+  - expected: hardware
+    patterns:
+      - hadware
+      - harrdware
+      - harddware
+
+# Allow to write `pattern` as RegExp
+# Can use $1...$9
+# Should wrap `/` and `/`
+  # ECMAScript
+  - expected: ECMAScript $1
+    patterns:
+      - /ECMAScript([0-9]+)/
+      - /ECMA Script([0-9]+)/
+    specs:
+      - from: ECMAScript2015
+        to:   ECMAScript 2015
+
+# expected contain pattern
+# https://github.com/azu/textlint-rule-prh/pull/8
+  - expected: ベンダー
+    pattern: /ベンダ(?!ー)/
+    specs:
+      - from: ベンダ
+        to: ベンダー
+      - from: ベンダー
+        to: ベンダー
+  # wordBoundary option
+  - expected: js
+  # === pattern: "/\b[JjＪｊ][SsＳｓ]\b/g"
+    options:
+      wordBoundary: true
+    specs:
+      - from: foo JS bar
+        to:   foo js bar
+      - from: foo altJS bar
+        to:   foo altJS bar
+```
+
+## Example
+
+See [azu/prh-textlint-example: Example of textlint + prh.](https://github.com/azu/prh-textlint-example "azu/prh-textlint-example: Example of textlint + prh.").
+
+
 ## Tests
 
     npm test

test/fixtures/prh.yml

@@ -0,0 +1,69 @@
+# prh version
+version: 1
+rules:
+
+  # format case-sensitive
+  - expected: Cookie
+  # the above is equal to following
+  # - expected: Cookie
+  #   pattern: "/[CcＣｃ][OoＯｏ][OoＯｏ][KkＫｋ][IiＩｉ][EeＥｅ]/g"
+  #   options:
+  #     wordBoundary: false
+  #   specs: []
+
+  # Write test to `expect`
+  - expected: jQuery
+    specs:
+      - from: jquery
+        to:   jQuery
+      - from: ＪＱＵＥＲＹ
+        to:   jQuery
+
+# If the `specs` is failed、fail to load prh.yml
+# - expected: JavaScript
+#   specs:
+#     - from: JAVASCRIPT
+#       to:   JavaScprit
+# Error: JavaScript spec failed. "JAVASCRIPT", expected "JavaScprit", but got "JavaScript", /[JjＪｊ][AaＡａ][VvＶｖ][AaＡａ][SsＳｓ][CcＣｃ][RrＲｒ][IiＩｉ][PpＰｐ][TtＴｔ]/g
+
+# pattern => expected
+  - expected: default
+    pattern:  deflaut
+
+# Allow to write multiple `pattern`
+  - expected: hardware
+    patterns:
+      - hadware
+      - harrdware
+      - harddware
+
+# Allow to write `pattern` as RegExp
+# Should wrap `/` and `/`
+  # ECMAScript
+  - expected: ECMAScript $1
+    patterns:
+      - /ECMAScript([0-9]+)/
+      - /ECMA Script([0-9]+)/
+    specs:
+      - from: ECMAScript2015
+        to:   ECMAScript 2015
+
+# expected contain pattern
+# https://github.com/azu/textlint-rule-prh/pull/8
+  - expected: ベンダー
+    pattern: /ベンダ(?!ー)/
+    specs:
+      - from: ベンダ
+        to: ベンダー
+      - from: ベンダー
+        to: ベンダー
+  # wordBoundary option
+  - expected: js
+  # === pattern: "/\b[JjＪｊ][SsＳｓ]\b/g"
+    options:
+      wordBoundary: true
+    specs:
+      - from: foo JS bar
+        to:   foo js bar
+      - from: foo altJS bar
+        to:   foo altJS bar