Parsing Line Termination - Issue ewaters#20

Introducting a new method in the Model to parse a line from the command
prompt and determine whether the command is complete.

For example - altsql> select * from film where title = ";
";

This failed because it stops at the end of the line even though we
are inside quotation marks.

lib/App/AltSQL/Model.pm

@@ -35,4 +35,86 @@ sub execute_sql {
 	return $sth;
 }
 
+sub parse_sql_line {
+    my ($self, $line, $in_something) = @_;
+
+    # first we parse to strip the strings and quotes
+    # if we are at the end of a line in a comment or string
+    # then we return the character that started it (i.e. ` ' " or /*)
+    # then assuming we're not in one of those we can then run this same
+    # regex to determine 1 or 0
+    my @chars = split //, $line;
+    my @sanitized_string;
+
+    $in_something //= '';
+    my $last_char;
+    CHAR: while(my $char = shift @chars)
+    {
+        if($in_something)
+        {
+            if($last_char eq '\\' && $in_something =~ /["'`]/) {
+                # this character is escaped. lets ignore it.
+                $last_char = '';
+                next CHAR;
+            }
+            if($char eq $in_something)
+            {
+                $in_something = '';
+            }
+            if($in_something eq '/*' && $char eq '/' && $last_char eq '*')
+            {
+                $in_something = '';
+            }
+        }
+        else
+        {
+            for my $start (qw/' " `/)
+            {
+                if($char eq $start) {
+                    if($last_char eq '\\') {
+                        last;
+                        # it's escaped
+                    }
+                    $in_something = $start;
+                }
+            }
+            if($char eq '*')
+            {
+                if($last_char eq '/')
+                {
+                    $in_something = '/*';
+                    pop @sanitized_string;
+                }
+            }
+            if($char eq '-')
+            {
+                if($last_char eq '-')
+                {
+                    $in_something = '--';
+                    pop @sanitized_string;
+                }
+            }
+            unless($in_something)
+            {
+                push @sanitized_string, $char;
+            }
+        }
+        $last_char = $char;
+    }
+    if($in_something eq '--')
+    {
+        $in_something = '';
+    }
+    return $in_something if $in_something;
+
+    $line = join '', @sanitized_string;
+    print STDERR $line, "\n";
+	if ($line =~ m{(;|\\G|\\c)\s*$} || $line =~ m{^\s*(quit|exit)\s*$} || $line =~ m{^\s*$}) {
+        return 1;
+	}
+	else {
+        return 0;
+	}
+}
+
 1;

lib/App/AltSQL/Term.pm

@@ -79,9 +79,9 @@ sub _build_term {
 sub return_key {
 	my $self = shift;
 
-	## The user has pressed the 'enter' key.  If the buffer ends in ';' or '\G', or if they've typed the bare word 'quit' or 'exit', accept the buffer
 	my $input = join ' ', @{ $self->term->{lines} };
-	if ($input =~ m{(;|\\G|\\c)\s*$} || $input =~ m{^\s*(quit|exit)\s*$} || $input =~ m{^\s*$}) {
+    my $ret = $self->app->model->parse_sql_line($input);
+	if ($ret eq '1') {
 		$self->term->accept_line();
 	}
 	else {

t/005_sql_parse_line.t

@@ -0,0 +1,39 @@
+use strict;
+use warnings;
+use Test::More;
+use Test::Deep;
+use App::AltSQL::Model;
+
+ok my $model = App::AltSQL::Model->new(app => 1);
+
+is $model->parse_sql_line('test'), 0, 'Incomplete statement';
+
+is $model->parse_sql_line('test;'), 1, 'Semicolon completes statement';
+
+is $model->parse_sql_line('quit'), 1, 'quit statement';
+
+is $model->parse_sql_line('exit'), 1, 'exit statement';
+
+is $model->parse_sql_line('   '), 1, 'blank space statement';
+
+is $model->parse_sql_line('test\G'), 1, '\G statement';
+
+is $model->parse_sql_line('test\c'), 1, '\c statement';
+
+is $model->parse_sql_line('select * from film where title = ";'), '"', 'Semi colon in string';
+is $model->parse_sql_line('";', '"'), 1, 'Tail end of statement where we were in a string';
+
+is $model->parse_sql_line('insert into mytab values (";",'), 0, 'Incomplete statement';
+
+is $model->parse_sql_line(q{select * from film where title = '\';}), "'", 'Semi colon in string';
+
+is $model->parse_sql_line(q{select * from film where title = "\";}), '"', 'Semi colon in string';
+
+is $model->parse_sql_line(q{select * from film where title = "\\\\";}), 1, 'Escaped slash, terminated string and end of statement';
+
+is $model->parse_sql_line(q{select * from film where title = /* "\";}), '/*', 'Semi colon in comment';
+is $model->parse_sql_line(q{*/ 'test';}, '/*'), 1, 'Statement terminated after comment closes';
+
+is $model->parse_sql_line(q{select 'test'; -- a simple statement}), 1, 'Statement terminated Got a comment after';
+
+done_testing;