[ci skip] Expand information on message options

Link to the more detailed message documentation when using a message option in validations.

1 files changed, 9 insertions, 3 deletions

diff --git a/guides/source/active_record_validations.md b/guides/source/active_record_validations.md
index 936d6a30b8..2737237c1a 100644
--- a/guides/source/active_record_validations.md
+++ b/guides/source/active_record_validations.md
@@ -392,7 +392,8 @@ The `exclusion` helper has an option `:in` that receives the set of values that
 will not be accepted for the validated attributes. The `:in` option has an
 alias called `:within` that you can use for the same purpose, if you'd like to.
 This example uses the `:message` option to show how you can include the
-attribute's value.
+attribute's value. For full options to the message argument please see the
+[message documentation](#message).
 
 The default error message is _"is reserved"_.
 
@@ -427,7 +428,8 @@ end
 The `inclusion` helper has an option `:in` that receives the set of values that
 will be accepted. The `:in` option has an alias called `:within` that you can
 use for the same purpose, if you'd like to. The previous example uses the
-`:message` option to show how you can include the attribute's value.
+`:message` option to show how you can include the attribute's value. For full
+options please see the [message documentation](#message).
 
 The default error message for this helper is _"is not included in the list"_.
 
@@ -768,6 +770,9 @@ class Coffee < ApplicationRecord
 end
 ```
 
+For full options to the message argument please see the
+[message documentation](#message).
+
 ### `:allow_blank`
 
 The `:allow_blank` option is similar to the `:allow_nil` option. This option
@@ -792,7 +797,8 @@ for each validation helper. The `:message` option accepts a `String` or `Proc`.
 
 A `String` `:message` value can optionally contain any/all of `%{value}`,
 `%{attribute}`, and `%{model}` which will be dynamically replaced when
-validation fails.
+validation fails. This replacement is done using the I18n gem, and the
+placeholders must match exactly, no spaces are allowed.
 
 A `Proc` `:message` value is given two arguments: the object being validated, and
 a hash with `:model`, `:attribute`, and `:value` key-value pairs.