docs(ngPattern): add note about using the g flag

Add a note to point out that using the `g` flag on the validation RegExp,
will cause each search to start at the index of the last search's match,
thus not taking the whole input value into account.

Closes angular#11917
Closes angular#11928

Author: gkalpak

src/ng/directive/input.js

@@ -46,9 +46,13 @@ var inputType = {
    *    as in the ngPattern directive.
    * @param {string=} ngPattern Sets `pattern` validation error key if the ngModel value does not match
    *    a RegExp found by evaluating the Angular expression given in the attribute value.
-   *    If the expression evaluates to a RegExp object then this is used directly.
-   *    If the expression is a string then it will be converted to a RegExp after wrapping it in `^` and `$`
-   *    characters. For instance, `"abc"` will be converted to `new RegExp('^abc$')`.
+   *    If the expression evaluates to a RegExp object, then this is used directly.
+   *    If the expression evaluates to a string, then it will be converted to a RegExp
+   *    after wrapping it in `^` and `$` characters. For instance, `"abc"` will be converted to
+   *    `new RegExp('^abc$')`.<br />
+   *    **Note:** Avoid using the `g` flag on the RegExp, as it will cause each successive search to
+   *    start at the index of the last search's match, thus not taking the whole input value into
+   *    account.
    * @param {string=} ngChange Angular expression to be executed when input changes due to user
    *    interaction with the input element.
    * @param {boolean=} [ngTrim=true] If set to false Angular will not automatically trim the input.
@@ -626,9 +630,13 @@ var inputType = {
    *    as in the ngPattern directive.
    * @param {string=} ngPattern Sets `pattern` validation error key if the ngModel value does not match
    *    a RegExp found by evaluating the Angular expression given in the attribute value.
-   *    If the expression evaluates to a RegExp object then this is used directly.
-   *    If the expression is a string then it will be converted to a RegExp after wrapping it in `^` and `$`
-   *    characters. For instance, `"abc"` will be converted to `new RegExp('^abc$')`.
+   *    If the expression evaluates to a RegExp object, then this is used directly.
+   *    If the expression evaluates to a string, then it will be converted to a RegExp
+   *    after wrapping it in `^` and `$` characters. For instance, `"abc"` will be converted to
+   *    `new RegExp('^abc$')`.<br />
+   *    **Note:** Avoid using the `g` flag on the RegExp, as it will cause each successive search to
+   *    start at the index of the last search's match, thus not taking the whole input value into
+   *    account.
    * @param {string=} ngChange Angular expression to be executed when input changes due to user
    *    interaction with the input element.
    *
@@ -720,9 +728,13 @@ var inputType = {
    *    as in the ngPattern directive.
    * @param {string=} ngPattern Sets `pattern` validation error key if the ngModel value does not match
    *    a RegExp found by evaluating the Angular expression given in the attribute value.
-   *    If the expression evaluates to a RegExp object then this is used directly.
-   *    If the expression is a string then it will be converted to a RegExp after wrapping it in `^` and `$`
-   *    characters. For instance, `"abc"` will be converted to `new RegExp('^abc$')`.
+   *    If the expression evaluates to a RegExp object, then this is used directly.
+   *    If the expression evaluates to a string, then it will be converted to a RegExp
+   *    after wrapping it in `^` and `$` characters. For instance, `"abc"` will be converted to
+   *    `new RegExp('^abc$')`.<br />
+   *    **Note:** Avoid using the `g` flag on the RegExp, as it will cause each successive search to
+   *    start at the index of the last search's match, thus not taking the whole input value into
+   *    account.
    * @param {string=} ngChange Angular expression to be executed when input changes due to user
    *    interaction with the input element.
    *
@@ -815,9 +827,13 @@ var inputType = {
    *    as in the ngPattern directive.
    * @param {string=} ngPattern Sets `pattern` validation error key if the ngModel value does not match
    *    a RegExp found by evaluating the Angular expression given in the attribute value.
-   *    If the expression evaluates to a RegExp object then this is used directly.
-   *    If the expression is a string then it will be converted to a RegExp after wrapping it in `^` and `$`
-   *    characters. For instance, `"abc"` will be converted to `new RegExp('^abc$')`.
+   *    If the expression evaluates to a RegExp object, then this is used directly.
+   *    If the expression evaluates to a string, then it will be converted to a RegExp
+   *    after wrapping it in `^` and `$` characters. For instance, `"abc"` will be converted to
+   *    `new RegExp('^abc$')`.<br />
+   *    **Note:** Avoid using the `g` flag on the RegExp, as it will cause each successive search to
+   *    start at the index of the last search's match, thus not taking the whole input value into
+   *    account.
    * @param {string=} ngChange Angular expression to be executed when input changes due to user
    *    interaction with the input element.
    *
@@ -1439,9 +1455,15 @@ function checkboxInputType(scope, element, attr, ctrl, $sniffer, $browser, $filt
  * @param {number=} ngMaxlength Sets `maxlength` validation error key if the value is longer than
  *    maxlength. Setting the attribute to a negative or non-numeric value, allows view values of any
  *    length.
- * @param {string=} ngPattern Sets `pattern` validation error key if the value does not match the
- *    RegExp pattern expression. Expected value is `/regexp/` for inline patterns or `regexp` for
- *    patterns defined as scope expressions.
+ * @param {string=} ngPattern Sets `pattern` validation error key if the ngModel value does not match
+ *    a RegExp found by evaluating the Angular expression given in the attribute value.
+ *    If the expression evaluates to a RegExp object, then this is used directly.
+ *    If the expression evaluates to a string, then it will be converted to a RegExp
+ *    after wrapping it in `^` and `$` characters. For instance, `"abc"` will be converted to
+ *    `new RegExp('^abc$')`.<br />
+ *    **Note:** Avoid using the `g` flag on the RegExp, as it will cause each successive search to
+ *    start at the index of the last search's match, thus not taking the whole input value into
+ *    account.
  * @param {string=} ngChange Angular expression to be executed when input changes due to user
  *    interaction with the input element.
  * @param {boolean=} [ngTrim=true] If set to false Angular will not automatically trim the input.
@@ -1472,9 +1494,15 @@ function checkboxInputType(scope, element, attr, ctrl, $sniffer, $browser, $filt
  * @param {number=} ngMaxlength Sets `maxlength` validation error key if the value is longer than
  *    maxlength. Setting the attribute to a negative or non-numeric value, allows view values of any
  *    length.
- * @param {string=} ngPattern Sets `pattern` validation error key if the value does not match the
- *    RegExp pattern expression. Expected value is `/regexp/` for inline patterns or `regexp` for
- *    patterns defined as scope expressions.
+ * @param {string=} ngPattern Sets `pattern` validation error key if the ngModel value does not match
+ *    a RegExp found by evaluating the Angular expression given in the attribute value.
+ *    If the expression evaluates to a RegExp object, then this is used directly.
+ *    If the expression evaluates to a string, then it will be converted to a RegExp
+ *    after wrapping it in `^` and `$` characters. For instance, `"abc"` will be converted to
+ *    `new RegExp('^abc$')`.<br />
+ *    **Note:** Avoid using the `g` flag on the RegExp, as it will cause each successive search to
+ *    start at the index of the last search's match, thus not taking the whole input value into
+ *    account.
  * @param {string=} ngChange Angular expression to be executed when input changes due to user
  *    interaction with the input element.
  * @param {boolean=} [ngTrim=true] If set to false Angular will not automatically trim the input.