Read MySQL username from my.cnf, too.

Resolves #353.

Changes

@@ -14,6 +14,8 @@ Revision history for Perl extension App::Sqitch
        runtime was using 32-bit integers. Fix by casting the version to text
        in the query, before Perl ever see it. Thanks to Malte Legenhausen for
        the report (#343).
+     - The MySQL engine will now read the username from MySQL configuration
+       files. Thanks to Eliot Alter for the bug report (#353).
 
 0.9996 2017-07-17T18:33:12Z
      - Fixed an error where Oracle sometimes truncated timestamp formats so

lib/App/Sqitch/Engine/mysql.pm

@@ -10,7 +10,7 @@ use Locale::TextDomain qw(App-Sqitch);
 use App::Sqitch::Plan::Change;
 use Path::Class;
 use Moo;
-use App::Sqitch::Types qw(DBH URIDB ArrayRef Bool Str);
+use App::Sqitch::Types qw(DBH URIDB ArrayRef Bool Str HashRef);
 use namespace::autoclean;
 use List::MoreUtils qw(firstidx);
 
@@ -39,24 +39,34 @@ sub registry_destination {
     return $uri->as_string;
 }
 
+has _mycnf => (
+    is => 'rw',
+    isa     => HashRef,
+    default => sub {
+        eval 'require MySQL::Config; 1' or return {};
+        return scalar MySQL::Config::parse_defaults('my', [qw(client mysql)]);
+    },
+);
+
+sub username {
+    my $self = shift;
+    return $self->SUPER::username || $self->_mycnf->{user};
+}
+
+sub password {
+    my $self = shift;
+    return $self->SUPER::password || $self->_mycnf->{password};
+}
+
 has dbh => (
     is      => 'rw',
     isa     => DBH,
     lazy    => 1,
     default => sub {
         my $self = shift;
         $self->use_driver;
-
         my $uri = $self->registry_uri;
-        my $pass = $self->password || do {
-            # Read the default MySQL configuration.
-            # http://dev.mysql.com/doc/refman/5.0/en/option-file-options.html
-            if (eval 'require MySQL::Config; 1') {
-                my %cfg = MySQL::Config::parse_defaults('my', [qw(client mysql)]);
-                $cfg{password};
-            }
-        };
-        my $dbh = DBI->connect($uri->dbi_dsn, scalar $self->username, $pass, {
+        my $dbh = DBI->connect($uri->dbi_dsn, scalar $self->username, $self->password, {
             PrintError           => 0,
             RaiseError           => 0,
             AutoCommit           => 1,

lib/sqitch-passwords.pod

@@ -99,12 +99,12 @@ contains lines specify authentication rules as follows:
 
 =item MySQL
 
-For MySQL, if the L<MySQL::Config> module is installed, passwords can be
-specified in the L<F</etc/my.cnf> and
-F<~/.my.cnf> files|http://dev.mysql.com/doc/refman/5.1/en/password-security-user.html#idm139947650158560>.
+For MySQL, if the L<MySQL::Config> module is installed, usernames and
+passwords can be specified in the
+L<F</etc/my.cnf> and F<~/.my.cnf> files|https://dev.mysql.com/doc/refman/5.7/en/password-security-user.html>.
 These files must limit access only to the current user (C<0600>). Sqitch will
-look for a password under the C<[client]> and C<[mysql]> sections, in that
-order.
+look for a username and password under the C<[client]> and C<[mysql]>
+sections, in that order.
 
 =item Oracle
 

lib/sqitch.pod

@@ -335,6 +335,8 @@ script templates.
 
 =item C<--quiet>
 
+  sqitch --quiet
+
 Suppress normal output messages. Error messages will still be emitted to
 C<STDERR>. Overrides any value specified by C<--verbose>.