require 'spec_helper'
require 'flydata/parser_provider'

describe 'MysqlAlterTableParser' do
  before do
    #load parser
    @parser_class = Mysql::ParserProvider.parser(:mysql, :mysql_alter_table)
  end

  let(:query) { "" }

  let(:parser) { @parser_class.new }
  subject { parser.parse(query).tree }


  describe '#parse' do

    context 'with alter table add column syntax' do

      context 'with normal alter table query' do
        let(:query) { "alter table test_table add column value varchar(26)" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              query: "add column value varchar(26)"
            }]
          })
        end
      end

      context 'with different column types' do
        context 'with longblob' do
          let(:query) { "alter table test_table add column value longblob" }
          it do
            expect(subject).to eq({
              type: :alter_table,
              table_name: "test_table",
              actions: [{
                action: :add_column,
                column: "value",
                type: "varbinary(4294967295)",
                query: "add column value longblob"
              }]
            })
          end
        end
      end

      context 'without the keyword "COLUMN"' do
        let(:query) { "alter table test_table add value varchar(26)" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              query: "add value varchar(26)"
            }]
          })
        end
      end

      context 'with multiple columns' do
        shared_examples 'test result hash' do
          it do
            expect(subject).to eq({
              type: :alter_table,
              table_name: "test_table",
              actions: [{
                action: :add_column,
                column: "value1",
                type: "varchar(78)",
                query: "#{expected_query}"
              },{
                action: :add_column,
                column: "value2",
                type: "varchar(78)",
                query: "#{expected_query}"
              }]
            })
          end
        end
        context 'with spaces before opening bracket' do
          let(:query) { "alter table test_table add column (value1 varchar(26), value2 varchar(26))" }
          let(:expected_query) {"add column (value1 varchar(26), value2 varchar(26))"}
          include_examples 'test result hash'
        end
        context 'without spaces before opening bracket' do
          let(:query) { "alter table test_table add column(value1 varchar(26), value2 varchar(26))" }
          let(:expected_query) {"add column(value1 varchar(26), value2 varchar(26))"}
          include_examples 'test result hash'
        end
      end

      context 'with multiple columns and without the keyword "COLUMN"' do
        let(:query) { "alter table test_table add ( value1 varchar(26), value2 varchar(26) )" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value1",
              type: "varchar(78)",
              query: "add ( value1 varchar(26), value2 varchar(26) )"
            },{
              action: :add_column,
              column: "value2",
              type: "varchar(78)",
              query: "add ( value1 varchar(26), value2 varchar(26) )"
            }]
          })
        end
      end

      context 'with multiple columns that have more detailed definitions,without the keyword "COLUMN"' do
        let(:query) { "alter table test_table add (value1 varchar(26) not null default 'flydata', value2 int auto_increment)" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value1",
              type: "varchar(78)",
              not_null: true,
              default: "flydata",
              query: "add (value1 varchar(26) not null default 'flydata', value2 int auto_increment)"
            },{
              action: :add_column,
              column: "value2",
              type: "int4",
              auto_increment: true,
              query: "add (value1 varchar(26) not null default 'flydata', value2 int auto_increment)"
            }]
          })
        end
      end

      context 'with backticks' do
        let(:query) { "alter table `test_table` add (`value1` varchar(26) not null default 'flydata', `value2` int auto_increment)" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value1",
              type: "varchar(78)",
              not_null: true,
              default: "flydata",
              query: "add (`value1` varchar(26) not null default 'flydata', `value2` int auto_increment)"
            },{
              action: :add_column,
              column: "value2",
              type: "int4",
              auto_increment: true,
              query: "add (`value1` varchar(26) not null default 'flydata', `value2` int auto_increment)"
            }]
          })
        end
      end

      context 'with after option' do
        let(:query) { "alter table test_table add column value varchar(26) after id" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              after: 'id',
              query: "add column value varchar(26) after id"
            }]
          })
        end
      end
      shared_examples "generating a flydata record for the given query" do
        let(:after_column_name) { 'id' }
        let(:actions) { %Q|add column value varchar(26) comment 'Ignorable comment' after #{after_column}| }
        let(:query) { %Q|alter table `test_table` #{actions}| }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              after: after_column_name,
              query: actions
            }]
          })
        end
      end
      context 'with after option, quoted after column name' do
        let(:after_column) { "`#{after_column_name}`" }

        it_behaves_like "generating a flydata record for the given query"
      end

      context 'with after option, backticks only on table name and a comment' do
        let(:after_column) { after_column_name }

        it_behaves_like "generating a flydata record for the given query"
      end

      context 'with first option' do
        let(:query) { "alter table test_table add column value varchar(26) first" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              position: :first,
              query: "add column value varchar(26) first"
            }]
          })
        end
      end

      context 'with first, unique' do
        let(:query) { "alter table test_table add column value varchar(26) UNIQUE first" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              unique: true,
              position: :first,
              query: "add column value varchar(26) UNIQUE first"
            }]
          })
        end
      end

      context "with default option" do
        shared_examples "a query parser parsing a query adding a column with a default value" do
          let(:query) { "alter table test_table add column col #{data_type} default #{value}" }
          it do
            is_expected.to eq({
              type: :alter_table,
              table_name: "test_table",
              actions: [{
                action: :add_column,
                column: "col",
                type: expected_data_type,
                default: expected_value,
                query: "add column col #{data_type} default #{value}"
              }]
            })
          end
        end

        context 'for timestamp column' do
          let(:data_type) { "timestamp" }
          let(:expected_data_type) { "datetime" }
          context 'taking current_timestamp' do
            let(:value) { "current_timestamp" }
            let(:expected_value) { "current_timestamp" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking localtime' do
            let(:value) { "localtime" }
            let(:expected_value) { "current_timestamp" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking localtimestamp' do
            let(:value) { "localtimestamp" }
            let(:expected_value) { "current_timestamp" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking now()' do
            let(:value) { "now()" }
            let(:expected_value) { "current_timestamp" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
        end

        context 'for integer column' do
          let(:data_type) { "int(11)" }
          let(:expected_data_type) { "int4(11)" }

          context 'taking a positive number without sign' do
            let(:value) { "1" }
            let(:expected_value) { "1" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a positive number' do
            let(:value) { "+1" }
            let(:expected_value) { "1" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a negative number' do
            let(:value) { "-1" }
            let(:expected_value) { "-1" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a negative number string' do
            let(:value) { %Q|'-1'| }
            let(:expected_value) { "-1" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking null' do
            let(:value) { %Q|NULL| }
            let(:expected_value) { nil }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
        end

        context 'for decimal column' do
          let(:data_type) { "decimal(10,2)" }
          let(:expected_data_type) { "numeric(10,2)" }

          context 'taking a positive number without sign' do
            let(:value) { "2.4" }
            let(:expected_value) { "2.4" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a positive number with sign' do
            let(:value) { "+0.4" }
            let(:expected_value) { "0.4" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a positive number no integer part' do
            let(:value) { ".05" }
            let(:expected_value) { "0.05" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a negative number' do
            let(:value) { "-20.43" }
            let(:expected_value) { "-20.43" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a negative number no integer part' do
            let(:value) { "-.43" }
            let(:expected_value) { "-0.43" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
        end

        context 'for varchar column' do
          let(:data_type) { "varchar(10)" }
          let(:expected_data_type) { "varchar(30)" }

          context 'taking null' do
            let(:value) { "NULL" }
            let(:expected_value) { nil }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking empty string' do
            let(:value) { %Q|''| }
            let(:expected_value) { "" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a string with spaces' do
            let(:value) { %Q|'0 0 0 0 0 0 0'| }
            let(:expected_value) { "0 0 0 0 0 0 0" }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a backslash' do
            let(:value) { %q|'\\\\'| }
            let(:expected_value) { %q|\\\\| }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
          context 'taking a string with special characters' do
            let(:value) { %q|'https://flydata.com $ \\\\\'\"\n\t'| }
            let(:expected_value) { %q|https://flydata.com $ \\\\\'\"\n\t| }

            it_behaves_like "a query parser parsing a query adding a column with a default value"
          end
        end
      end

      context 'with null option' do
        let(:length) { 45 }
        let(:query) { "alter table test_table add column extra varchar(#{length}) null" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "extra",
              type: "varchar(#{length * 3})",
              query: "add column extra varchar(#{length}) null"
            }]
          })
        end
      end
    end

    context 'with alter table drop column syntax' do
      let(:query) { "alter table test_table drop column value" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "drop column value"
          }])
      end
    end

    context 'without column keyword' do
      let(:query) { "alter table test_table drop value" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "drop value"
          }])
      end
    end

    context 'when column_name is wrapped with backquote' do
      let(:query) { "alter table test_table drop `value`" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "drop `value`"
          }])
      end
    end

    context 'when table_name is wrapped with backquote' do
      let(:query) { "alter table `test_table` drop value" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "drop value"
          }])
      end
    end

    context 'when keywords are capitalized' do
      let(:query) { "ALTER TABLE `test_table` DROP value" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "DROP value"
          }])
      end
    end

    context 'when table_name includes schema' do
      let(:query) { "alter table test_schema.test_table drop value" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          schema_name: "test_schema",
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "drop value"
          }])
      end
    end

    context 'when table_name includes schema with quotes' do
      let(:query) { "alter table `test_schema`.`test_table` drop `value`" }
      it do
        expect(subject).to eq(
          type: :alter_table,
          schema_name: "test_schema",
          table_name: "test_table",
          actions: [{
            action: :drop_column,
            column: "value",
            query: "drop `value`"
          }])
      end
    end

    context 'with multiple alter specs' do
      context 'with add column and drop column' do
        let(:query) { "alter table test_table add column value varchar(26) after id, drop old_value" }
        it do
          expect(subject).to eq({
            type: :alter_table,
            table_name: "test_table",
            actions: [{
              action: :add_column,
              column: "value",
              type: "varchar(78)",
              after: 'id',
              query: "add column value varchar(26) after id"
            },{
              action: :drop_column,
              column: "old_value",
              query: "drop old_value"
            }]
          })
        end
      end
    end

    let(:query) { "ALTER TABLE `test_schema`.`test_table` #{alter_table_action}" }
    shared_examples "a parser parsing a single action alter table query" do
      it do
        is_expected.to eq({
          type: :alter_table,
          schema_name: "test_schema",
          table_name: "test_table",
          actions: [action_hash]
        })
      end
    end
    shared_examples "a parser raising an error" do
      it do
        expect { subject }.to raise_error
      end
    end
    shared_examples "a parser parsing a nonbreaking query" do
      let(:action_hash) {
          {
            action: action,
            support_level: :nonbreaking,
            query: alter_table_action,
          }
      }
      it_behaves_like "a parser parsing a single action alter table query"
    end
    shared_examples "a parser parsing a breaking query" do
      let(:action_hash) {
        {
          action: action,
          query: alter_table_action,
        }
      }
      it_behaves_like "a parser parsing a single action alter table query"
    end
    shared_examples "a debug parser" do
      it do
        puts query
        result = parser.parse(query)
        p result
        puts "FAILURE: #{parser.failure_reason}"
      end
    end
    shared_examples "test normal key options" do |*examples|
      context "with normal key options" do
        context "key_block_size" do
          let(:normal_key_options) { " KEY_BLOCK_SIZE = 102400" }
          it_behaves_like *examples
        end
        context "key_block_size with no space" do
          let(:normal_key_options) { " KEY_BLOCK_SIZE=102400" }
          it_behaves_like *examples
        end
        context "key_block_size no equal sign" do
          let(:normal_key_options) { " KEY_BLOCK_SIZE 102400" }
          it_behaves_like *examples
        end
        context "using" do
          let(:normal_key_options) { " using btree" }
          it_behaves_like *examples
        end
        context "comment" do
          let(:normal_key_options) { " comment 'Hello World!'" }
          it_behaves_like *examples
        end
        context "key_block_size and comment" do
          let(:normal_key_options) { " KEY_BLOCK_SIZE 102400 comment 'Hello World!'" }
          it_behaves_like *examples
        end
        context "none" do
          it_behaves_like *examples do
            let(:normal_key_options) { "" }
          end
        end
      end
    end
    shared_examples "test key list without order" do |*examples|
      context "with a single key" do
        it_behaves_like *examples do
          let(:key_list) { " testKey" }
          let(:expected_key_list) { [ "testKey" ] }
        end
      end
      context "with a quoted single key" do
        it_behaves_like *examples do
          let(:key_list) { " `testKey`" }
          let(:expected_key_list) { [ "testKey" ] }
        end
      end
      context "with multiple keys" do
        it_behaves_like *examples do
          let(:key_list) { " testKey1, testKey2" }
          let(:expected_key_list) { [ "testKey1", "testKey2" ] }
        end
      end
    end
    shared_examples "test key list" do |*examples|
      include_examples "test key list without order", *examples
      context "with multiple keys with order" do
        it_behaves_like *examples do
          let(:key_list) { " testKey1 ASC, testKey2 desc" }
          let(:expected_key_list) { [ "testKey1 asc", "testKey2 desc" ] }
        end
      end
    end

    shared_examples "test constraint keyword" do |*examples|
      context "with constraint keyword" do
        context "with backticked constraint name" do
          it_behaves_like *examples do
            let(:constraint_keyword) { " CONSTRAINT `chkName`" }
          end
        end
        context "with constraint name" do
          it_behaves_like *examples do
            let(:constraint_keyword) { " CONSTRAINT chkName" }
          end
        end
        context "without constraint name" do
          it_behaves_like *examples do
            let(:constraint_keyword) { " CONSTRAINT" }
          end
        end
      end
      context "without constraint keyword" do
        it_behaves_like  *examples do
          let(:constraint_keyword) { "" }
        end
      end
    end
    shared_examples "test key name" do |*examples|
      context "with key name" do
        it_behaves_like *examples do
          let(:key_name) { " testKey" }
        end
      end
      context "without key name" do
        it_behaves_like *examples do
          let(:key_name) { "" }
        end
      end
      context "with quoted key name" do
        it_behaves_like *examples do
          let(:key_name) { " `testKey`" }
        end
      end
    end
    shared_examples "test key or index" do |*examples|
      context "with key" do
        it_behaves_like *examples do
          let(:key_or_index) { " KEY" }
        end
      end
      context "with index" do
        it_behaves_like  *examples do
          let(:key_or_index) { " index" }
        end
      end
    end
    shared_examples "test optional key or index" do |*examples|
      include_examples "test key or index", *examples
      context "with none" do
        it_behaves_like *examples do
          let(:key_or_index) { "" }
        end
      end
    end
    shared_examples "test using option" do |*examples|
      context "with BTREE" do
        it_behaves_like *examples do
          let(:using_option) { " USING BTREE" }
        end
      end
      context "with hash" do
        it_behaves_like *examples do
          let(:using_option) { " using hash" }
        end
      end
      context "with none" do
        it_behaves_like *examples do
          let(:using_option) { "" }
        end
      end
    end
    shared_examples "test identifier combination without ." do |*examples|
      it_behaves_like "test identifier", *examples do
        let(:identifier) { " #{ident}" }
      end
    end
    shared_examples "test identifier combination with single ." do |*examples|
      it_behaves_like "test identifier", *examples do
        let(:identifier) { " #{ident}.#{ident}" }
      end
    end
    shared_examples "test identifier combination with single . starting with ." do |*examples|
      it_behaves_like "test identifier", *examples do
        let(:identifier) { " .#{ident}" }
      end
    end
    shared_examples "test identifier combination with two ." do |*examples|
      it_behaves_like "test identifier", *examples do
        let(:identifier) { " #{ident}.#{ident}.#{ident}" }
      end
    end
    shared_examples "test identifier combination with two . starting with ." do |*examples|
      it_behaves_like "test identifier", *examples do
        let(:identifier) { " .#{ident}.#{ident}" }
      end
    end
    shared_examples "test field identifier" do |*examples|
      it_behaves_like "test identifier combination without .", *examples
      it_behaves_like "test identifier combination with single .", *examples
      it_behaves_like "test identifier combination with two .", *examples
    end
    shared_examples "test identifier" do |*examples|
      context "unquoted identifier" do
        it_behaves_like *examples do
          let(:ident) {"test_ident1"}
        end
      end
      context "quoted identifier" do
        it_behaves_like *examples do
          let(:ident) {"`test_ident1`"}
        end
      end
    end
    shared_examples "test optional to" do |*examples|
      context "with to" do
        it_behaves_like *examples do
          let(:opt_to) {" TO "}
        end
      end
      context "with =" do
        it_behaves_like *examples do
          let(:opt_to) {" = "}
        end
      end
      context "with = without spaces" do
        it_behaves_like *examples do
          let(:opt_to) {"="}
        end
      end
      context "with AS" do
        it_behaves_like *examples do
          let(:opt_to) {" as "}
        end
      end
      context "with none" do
        it_behaves_like *examples do
          let(:opt_to) { "" }
        end
      end
    end
    shared_examples "test table identifier" do |*examples|
      it_behaves_like "test identifier combination without .", *examples
      it_behaves_like "test identifier combination with single .", *examples
      it_behaves_like "test identifier combination with single . starting with .", *examples
    end
    shared_examples "test simple identifier" do |*examples|
      it_behaves_like "test identifier combination without .", *examples
      it_behaves_like "test identifier combination with single .", *examples
      it_behaves_like "test identifier combination with two .", *examples
      it_behaves_like "test identifier combination with two . starting with .", *examples
    end
    shared_examples "test order" do |*examples|
      context "ascending" do
        it_behaves_like *examples do
          let(:order){" ASC"}
        end
      end
      context "descending" do
        it_behaves_like *examples do
          let(:order){" desc"}
        end
      end
      context "no order" do
        it_behaves_like *examples do
          let(:order){""}
        end
      end
    end
    shared_examples "test charset" do |*examples|
      ["CHARACTER SET", "charset"].each do |charset|
        context "charset is #{charset}" do
          it_behaves_like *examples do
            let(:charset){"#{charset}"}
          end
        end
      end
    end
    shared_examples "test charsetname" do |*examples|
      ["default","binary","utf8","latin1"].each do |charsetname|
        context "charsetname is #{charsetname}" do
          it_behaves_like *examples do
            let(:charsetname){"#{charsetname}"}
          end
        end
      end
    end
    shared_examples "test collate" do |*examples|
      ["collate default", "collate utf8_general_ci", "collate latin1_bin"].each do |collate|
        context "collate is #{collate}" do
          it_behaves_like *examples do
            let(:collate){"#{collate}"}
          end
        end
      end
    end
    shared_examples "test collate with equals" do |*examples|
      ["collate=default", "collate = utf8_general_ci"].each do |collate|
        context "collate is #{collate}" do
          it_behaves_like *examples do
            let(:collate){"#{collate}"}
          end
        end
      end
    end
    shared_examples "test optional default" do |*examples|
      context "with default" do
        it_behaves_like *examples do
          let(:default){"default "}
        end
      end
      context "without default" do
        it_behaves_like *examples do
          let(:default){""}
        end
      end
    end
    shared_examples "test optional no_write_to_binlog" do |*examples|
      context "with no_write_to_binlog" do
        it_behaves_like *examples do
          let(:no_write_to_binlog){" no_write_to_binlog"}
        end
      end
      context "with local" do
        it_behaves_like *examples do
          let(:no_write_to_binlog){" LOCAL"}
        end
      end
      context "without local or no_write_to_binlog flag" do
        it_behaves_like *examples do
          let(:no_write_to_binlog){""}
        end
      end
    end
    shared_examples "test partition names" do |*examples|
      context "ALL" do
        it_behaves_like *examples do
          let(:partition_names){"ALL"}
        end
      end
      context "ALL lower case" do
        it_behaves_like *examples do
          let(:partition_names){"all"}
        end
      end
      context "single partition" do
        it_behaves_like *examples do
          let(:partition_names){"p0"}
        end
      end
      context "multiple partitions" do
        it_behaves_like *examples do
          let(:partition_names){"p0,P1, p2"}
        end
      end
    end
    shared_examples "test check types" do |*examples|
      ["quick", "FAST", "medium", "EXTENDED", "CHANGED", "for upgrade"].each do |check_type|
        context "check_type is #{check_type}" do
          it_behaves_like *examples do
            let(:check_type) {check_type}
          end
        end
      end
      context "multiple check types" do
        it_behaves_like *examples do
          let(:check_type) {"fast for upgrade"}
        end
      end
    end
    shared_examples "test repair types" do |*examples|
      ["quick", "EXTENDED", "use_frm"].each do |repair_type|
        context "repair_type is #{repair_type}" do
          it_behaves_like *examples do
            let(:repair_type) {repair_type}
          end
        end
      end
      context "multiple repair types" do
        it_behaves_like *examples do
          let(:repair_type) {"quick USE_FRM"}
        end
      end
    end
    shared_examples "test optional validation" do |*examples|
      context "with validation" do
        it_behaves_like *examples do
          let(:validation){" with validation"}
        end
      end
      context "without validation" do
        it_behaves_like *examples do
          let(:validation){" WITHOUT VALIDATION"}
        end
      end
      context "none" do
        it_behaves_like *examples do
          let(:validation){""}
        end
      end
    end
    shared_examples "test optional equal" do |*examples|
      context "with EQ" do
        it_behaves_like *examples do
          let(:equal){"="}
        end
      end
      context "with EQ and a space before it" do
        it_behaves_like *examples do
          let(:equal){" ="}
        end
      end
      context "with SET_VAR" do
        it_behaves_like *examples do
          let(:equal){":="}
        end
      end
      context "with none" do
        it_behaves_like *examples do
          let(:equal){""}
        end
      end
    end
    shared_examples "test signed literal" do |*examples|
      context "number literal" do
        it_behaves_like *examples do
          let(:signed_literal){"100"}
        end
      end
      context "signed number literal" do
        it_behaves_like *examples do
          let(:signed_literal){"100"}
        end
      end
      context "signed number literal within quotes" do
        it_behaves_like *examples do
          let(:signed_literal){"'+100'"}
        end
      end
      context "null" do
        it_behaves_like *examples do
          let(:signed_literal){"NULL"}
        end
      end
      context "boolean" do
        it_behaves_like *examples do
          let(:signed_literal){"TRUE"}
        end
      end
      context "quoted string" do
        it_behaves_like *examples do
          let(:signed_literal){"'Hello World!'"}
        end
      end
    end
    shared_examples "test optional reference list" do |*examples|
      context "with no references" do
        it_behaves_like *examples do
          let(:opt_ref_list) {""}
        end
      end
      context "with single reference" do
        it_behaves_like *examples do
          let(:opt_ref_list) {"(id)"}
        end
      end
      context "with multiple references" do
        it_behaves_like *examples do
          let(:opt_ref_list) {" (id_1, id2)"}
        end
      end
    end
    shared_examples "test optional match clause" do |*examples|
      context "no match clause" do
        it_behaves_like *examples do
          let(:opt_match_clause) {""}
        end
      end
      context "match full" do
        it_behaves_like *examples do
          let(:opt_match_clause) {" MATCH FULL"}
        end
      end
      context "match partial" do
        it_behaves_like *examples do
          let(:opt_match_clause) {" match PARTIAL"}
        end
      end
    end
    shared_examples "test optional on update delete" do |*examples|
      context "no on update delete clause" do
        it_behaves_like *examples do
          let(:opt_on_update_delete) {""}
        end
      end
      context "on update and on delete" do
        it_behaves_like "test delete option", *examples do
          let(:opt_on_update_delete) {" on update #{delete_option} on delete #{delete_option}"}
        end
      end
      context "on update only" do
        it_behaves_like "test delete option", *examples do
          let(:opt_on_update_delete) {" ON UPDATE #{delete_option}"}
        end
      end
    end
    shared_examples "test delete option" do |*examples|
      context "restrict" do
        it_behaves_like *examples do
          let(:delete_option) {"restrict"}
        end
      end
      context "set null" do
        it_behaves_like *examples do
          let(:delete_option) {"SET NULL"}
        end
      end
    end
    context 'add index' do
      let(:action) { :add_index }
      context "with a simple add index" do
        let(:alter_table_action) { "ADD INDEX `test` (`t_now`)" }
        it_behaves_like "a parser parsing a nonbreaking query"
      end
      context "with a simple add index and without space before the opening bracket" do
        let(:alter_table_action) { "ADD INDEX `test`(`t_now`)" }
        it_behaves_like "a parser parsing a nonbreaking query"
      end
      context "with a simple add index with order" do
        let(:alter_table_action) { "ADD INDEX `test` (`t_now` ASC)" }
        it_behaves_like "a parser parsing a nonbreaking query"
      end
      context "with an add index with multiple fields" do
        let(:key_list) { "`t_now` ASC, `t_timestamp` DESC" }
        let(:alter_table_action) { "ADD INDEX `test` (#{key_list})" }
        it_behaves_like "a parser parsing a nonbreaking query"

        context "with spaces around key list" do
          let(:key_list) { " `t_now` ASC, `t_timestamp` DESC " }
          it_behaves_like "a parser parsing a nonbreaking query"
        end

        context "with a field without order" do
          let(:key_list) { " `t_now` ASC, `t_timestamp`" }
          it_behaves_like "a parser parsing a nonbreaking query"
        end
      end
      context "with an add index with no index name" do
        let(:alter_table_action) { "ADD INDEX (`t_now` ASC)" }
        it_behaves_like "a parser parsing a nonbreaking query"
      end
      context "with an add index with USING" do
        let(:using_option) { "USING BTREE" }
        let(:alter_table_action) { "ADD INDEX `test` #{using_option} (`t_now` ASC)" }
        it_behaves_like "a parser parsing a nonbreaking query"

        context "without index name" do
          let(:alter_table_action) { "ADD INDEX #{using_option} (`t_now` ASC)" }
          it_behaves_like "a parser parsing a nonbreaking query"
        end

        context "without index name and without space before the opening bracket" do
          let(:alter_table_action) { "ADD INDEX #{using_option}(`t_now` ASC)" }
          it_behaves_like "a parser parsing a nonbreaking query"
        end

        context "with hash" do
          let(:using_option) { "USING hash" }
          it_behaves_like "a parser parsing a nonbreaking query"
        end
      end
      context "with normal key options" do
        let(:alter_table_action) { "ADD INDEX (`t_now` ASC)#{normal_key_options}" }
        it_behaves_like "test normal key options", "a parser parsing a nonbreaking query"
      end
    end
    context "fulltext or spatial" do
      let(:action) { :add_index }
      shared_examples "test all permutations" do |examples|
        context "key_or_index" do
          shared_examples "a parser parsing a nonbreaking query with key options" do
            let(:alter_table_action) { "ADD #{fulltext_or_spatial} #{key_or_index} #{key_name} (test_column)#{key_options}" }
            context "no key option" do
              it_behaves_like "a parser parsing a nonbreaking query" do
                let(:key_options) { "" }
              end
            end
            context "key_block_size" do
              it_behaves_like "a parser parsing a nonbreaking query" do
                let(:key_options) { " KEY_BLOCK_SIZE 2048" }
              end
            end
            context "comment" do
              it_behaves_like "a parser parsing a nonbreaking query" do
                let(:key_options) { " COMMENT 'Hello World!'" }
              end
            end
            context "comment and key_block_size" do
              it_behaves_like "a parser parsing a nonbreaking query" do
                let(:key_options) { " KEY_BLOCK_SIZE = 1024 COMMENT 'Hello World!'" }
              end
            end
          end
          shared_examples "a parser parsing a nonbreaking query with key options fulltext" do
            it_behaves_like "a parser parsing a nonbreaking query with key options"
            let(:alter_table_action) { "ADD #{fulltext_or_spatial} #{key_or_index} #{key_name} (test_column)#{key_options}" }
            context "with parser" do
              it_behaves_like "a parser parsing a nonbreaking query" do
                let(:key_options) { " WITH PARSER test_parser" }
              end
            end
          end
          shared_examples "a parser parsing a query with either key or index" do |*examples|
            let(:alter_table_action) { "ADD #{fulltext_or_spatial} #{key_or_index} #{key_name} (test_column)" }
            context "no key name" do
              it_behaves_like *examples do
                let(:key_name) { "" }
              end
            end
            context "simple key name" do
              it_behaves_like *examples do
                let(:key_name) { "test_key" }
              end
            end
            context "quoted key name" do
              it_behaves_like *examples do
                let(:key_name) { "`test_key`" }
              end
            end
          end
          it_behaves_like "test optional key or index", "a parser parsing a query with either key or index", examples
        end
      end
      context "with fulltext" do
        it_behaves_like "test all permutations",  "a parser parsing a nonbreaking query with key options fulltext" do
          let(:fulltext_or_spatial) { "FULLTEXT" }
        end
      end
      context "with spatial" do
        it_behaves_like "test all permutations",  "a parser parsing a nonbreaking query with key options" do
          let(:fulltext_or_spatial) { "SPATIAL" }
        end
      end
    end
    context "check constraint" do
      let(:action) { :add_check_constraint }
      let(:alter_table_action) { "ADD#{constraint_keyword} CHECK (#{constraint_expr})" }
      shared_examples "test constraint expr" do
        context "with constraint expr" do
          it_behaves_like "test constraint keyword", "a parser parsing a nonbreaking query" do
            let(:constraint_expr) { "P_Id>0 AND City='Sandnes'" }
          end
        end
      end

      context "test all" do
        it_behaves_like "test constraint expr"
      end
    end
    context "unique constraint" do
      let(:action) { :add_unique_constraint }
      let(:alter_table_action) { "ADD#{constraint_keyword} UNIQUE#{key_or_index}#{key_name}#{using_option} (#{key_list})#{normal_key_options}" }

      it_behaves_like "test constraint keyword", "test optional key or index",
                      "test key name", "test using option", "test key list",
                      "test normal key options",
#                      "a debug parser"
                      "a parser parsing a nonbreaking query"
    end
    context "primary key constraint" do
      let(:alter_table_action) { "ADD#{constraint_keyword} PRIMARY KEY#{key_name}#{using_option} (#{key_list})#{normal_key_options}" }
      let(:action) { :add_primary_key_constraint }
      let(:action_hash) {
        {
          action: action,
          keys: expected_key_list,
          query: alter_table_action,
        }
      }

      it_behaves_like "test constraint keyword",
                      "test key name", "test using option", "test key list",
                      "test normal key options",
#                      "a debug parser"
                      "a parser parsing a single action alter table query"
    end
    context 'add foreign key' do
      let(:action) { :add_foreign_key_constraint }
      let(:alter_table_action) { "add#{constraint_keyword} foreign key#{key_name}(#{key_list}) references employees#{opt_ref_list}#{opt_match_clause}#{opt_on_update_delete}"}
      it_behaves_like "test constraint keyword",
                      "test key name", "test key list without order",
                      "test optional reference list",
                      "test optional match clause",
                      "test optional on update delete",
                      "a parser parsing a nonbreaking query"
    end
    context "enable keys" do
      let(:alter_table_action) { "ENABLE KEYS" }
      let(:action) { :enable_keys }
      it_behaves_like "a parser parsing a nonbreaking query"
    end
    context "disable keys" do
      let(:alter_table_action) { "DISABLE KEYS" }
      let(:action) { :disable_keys }
      it_behaves_like "a parser parsing a nonbreaking query"
    end
    context "drop primary key" do
      let(:alter_table_action) { "DROP PRIMARY KEY" }
      let(:action) { :drop_primary_key }

      it_behaves_like "a parser parsing a breaking query"
    end
    context "drop foreign key" do
      let(:alter_table_action) { "DROP FOREIGN KEY#{identifier}" }
      let(:action) { :drop_foreign_key }

      it_behaves_like "test field identifier", "a parser parsing a nonbreaking query"
    end
    context "drop key or index" do
      let(:alter_table_action) { "DROP#{key_or_index}#{identifier}" }
      let(:action) { "drop_#{key_or_index.strip.downcase}".to_sym }

      it_behaves_like "test key or index", "test field identifier", "a parser parsing a nonbreaking query"
    end
    context "rename table" do
      let(:alter_table_action) { "rename#{opt_to}#{identifier}" }
      let(:action) { :rename_table }

      it_behaves_like "test optional to", "test table identifier", "a parser parsing a breaking query"
      context "exception cases" do
        context "with as followed by quoted identifier and no space in between" do
          let(:alter_table_action) { "rename as`test_ident1`" } #strange, but valid
          it_behaves_like "a parser parsing a breaking query"
        end
        context "with to followed by quoted identifier and no space in between" do
          let(:alter_table_action) { "rename to`test_ident1`" }
          it_behaves_like "a parser parsing a breaking query"
        end
        context "no space between rename and to" do
          let(:alter_table_action) { "renameto `test_ident1`" }
          it_behaves_like "a parser raising an error"
        end
        context "no space between to and table name" do
          let(:alter_table_action) { "rename totest_ident1" }
          describe "'totest_ident1' is treated as a table name" do
            it_behaves_like "a parser parsing a breaking query"
          end
        end
      end
    end
    context "rename key or index" do
      let(:alter_table_action) { "rename#{key_or_index}#{identifier} TO#{identifier}" }
      let(:action) { :rename_key_or_index }

      it_behaves_like "test key or index", "test field identifier", "a parser parsing a nonbreaking query"
    end
    context "order by" do
      let(:action) { :order_table }
      context "with single column" do
        let(:alter_table_action) { "order by#{identifier}#{order}" }
        it_behaves_like "test simple identifier", "test order", "a parser parsing a breaking query"
      end
      context "with multiple columns" do
        let(:alter_table_action) { "order by#{identifier}#{order},#{identifier}#{order},#{identifier}#{order}" }
        it_behaves_like "test simple identifier", "test order", "a parser parsing a breaking query"
      end
    end
    context "convert to charset" do
      let(:action) { :convert_charset }
      context "test with collate" do
        let(:alter_table_action) { "convert to #{charset} #{charsetname} #{collate}" }
        it_behaves_like "test charset", "test charsetname", "test collate", "a parser parsing a breaking query"
      end
      context "test without collate" do
        let(:alter_table_action) { "convert to #{charset} #{charsetname}" }
        it_behaves_like "test charset", "test charsetname", "a parser parsing a breaking query"
      end
    end
    context "default charset" do
      let(:action) { :default_charset }
      context "with collate" do
        let(:alter_table_action) { "#{default}#{charset}=#{charsetname} #{collate}" }
        it_behaves_like "test optional default", "test charset",  "test charsetname", "test collate", "a parser parsing a breaking query"
        it_behaves_like "test optional default",  "test charset", "test charsetname", "test collate with equals", "a parser parsing a breaking query"
      end
      context "without collate" do
        let(:alter_table_action) { "#{default}#{charset} #{charsetname}" }
        it_behaves_like "test optional default", "test charset",  "test charsetname", "a parser parsing a breaking query"
      end
      context "without charset" do
      #The doc at http://dev.mysql.com/doc/refman/5.6/en/alter-table.html does not indicate that
      #charset is optional. But this works (tested on mysql 5.5.38)
        let(:alter_table_action) { "#{default}#{collate}" }
        it_behaves_like  "test optional default","test collate", "a parser parsing a breaking query"
        it_behaves_like  "test optional default","test collate with equals", "a parser parsing a breaking query"
      end
    end
    context "force" do
      let(:alter_table_action) { "force" }
      let(:action) { :force }
      it_behaves_like "a parser parsing a nonbreaking query"
    end
    context "discard tablespace" do
      let(:alter_table_action) { "discard tablespace" }
      let(:action) { :discard_tablespace }
      it_behaves_like "a parser parsing a breaking query"
    end
    context "import tablespace" do
      let(:alter_table_action) { "import tablespace" }
      let(:action) { :import_tablespace }
      it_behaves_like "a parser parsing a breaking query"
    end
    context "add partition" do
      let(:action) { :add_partition }
      context "simple definition with spaces" do
        let(:alter_table_action) { "add partition#{no_write_to_binlog} (PARTITION p2)" }
        it_behaves_like "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
      context "complex partition definition without spaces" do
        let(:alter_table_action) { "ADD partition#{no_write_to_binlog}(PARTITION p2 VALUES LESS THAN (800))" }
        it_behaves_like "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
    end
    context "drop partition" do
      let(:action) { :drop_partition }
      context "drop single partition" do
        let(:alter_table_action) { "DROP partition p0" }
        it_behaves_like "a parser parsing a nonbreaking query"
      end
      context "drop multiple partitions" do
        context "upcase and spaces between partition names" do
          let(:alter_table_action) { "DROP PARTITION p0, p1" }
          it_behaves_like "a parser parsing a nonbreaking query"
        end
        context "lowercase and no spaces between partition names" do
          let(:alter_table_action) { "drop partition p0,p1,p2" }
          it_behaves_like "a parser parsing a nonbreaking query"
        end
      end
    end
    context "rebuild, optimize, analyze partitions" do
      ["rebuild", "optimize", "analyze"].each do |op|
        context "#{op} partition" do
          let(:action) { "#{op}_partition".to_sym }
          context "with upcase op" do
            let(:alter_table_action) { "#{op.upcase} PARTITION#{no_write_to_binlog} #{partition_names}" }
            it_behaves_like "test partition names", "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
          end
          context "with lowercase op" do
            let(:alter_table_action) { "#{op} partition#{no_write_to_binlog} #{partition_names}" }
            it_behaves_like "test partition names", "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
          end
        end
      end
    end
    context "check partition" do
      let(:action) { :check_partition }
      context "without check_type" do
        let(:alter_table_action) { "CHECK PARTITION #{partition_names}" }
        it_behaves_like "test partition names", "a parser parsing a nonbreaking query"
      end
      context "with check type" do
        let(:alter_table_action) { "check partition #{partition_names} #{check_type}" }
        it_behaves_like "test check types", "test partition names", "a parser parsing a nonbreaking query"
      end
    end
    context "repair partition" do
      let(:action) { :repair_partition }
      context "without repair_type" do
        let(:alter_table_action) { "REPAIR PARTITION#{no_write_to_binlog} #{partition_names}" }
        it_behaves_like "test partition names", "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
      context "with repair type" do
        let(:alter_table_action) { "repair partition#{no_write_to_binlog} #{partition_names} #{repair_type}" }
        it_behaves_like "test repair types", "test partition names", "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
    end
    context "coalesce partition" do
      let(:action) { :coalesce_partition }
      context "single digit partition number" do
        let(:alter_table_action) { "coalesce partition#{no_write_to_binlog} 1" }
        it_behaves_like "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
      context "double digit partition number" do
        let(:alter_table_action) { "COALESCE PARTITION#{no_write_to_binlog} 22" }
        it_behaves_like "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
    end
    context "truncate partition" do
      let(:action) { :truncate_partition }
      let(:alter_table_action) { "TRUNCATE PARTITION #{partition_names}" }
      it_behaves_like "test partition names", "a parser parsing a nonbreaking query"
    end
    context "reorganize partition" do
      let(:action) { :reorganize_partition }
      context "simple definition without partition names and partition definition" do
        let(:alter_table_action) { "reorganize partition#{no_write_to_binlog}" }
        it_behaves_like "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
      context "complex partition definition" do
        let(:alter_table_action) { "REORGANIZE PARTITION#{no_write_to_binlog} p0 INTO (PARTITION n0 VALUES LESS THAN (1960))" }
        it_behaves_like "test optional no_write_to_binlog", "a parser parsing a nonbreaking query"
      end
    end
    context "exchange partition" do
      let(:action) { :exchange_partition }
      let(:alter_table_action) { "EXCHANGE PARTITION #{ident} with table#{identifier}#{validation}" }
      it_behaves_like "test table identifier", "test optional validation", "a parser parsing a nonbreaking query"
    end
    context "discard and import partition tablespace" do
      ["discard", "import"].each do |op|
        context "#{op}" do
          let(:action) {"#{op}_partition_tablespace".to_sym}
          let(:alter_table_action) {"#{op} PARTITION #{partition_names} TABLESPACE"}
          it_behaves_like "test partition names", "a parser parsing a nonbreaking query"
        end
      end
    end
    context "remove partitioning" do
      let(:action) {:remove_partitioning}
      let(:alter_table_action) { "REMOVE PARTITIONING" }
      it_behaves_like "a parser parsing a nonbreaking query"
    end

    ## Change and modify column related tests
    shared_examples "test optional column" do |*examples|
      context "with column" do
        it_behaves_like *examples do
          let(:column) {" COLUMN"}
        end
      end
      context "without column" do
        it_behaves_like *examples do
          let(:column) { "" }
        end
      end
    end
    shared_examples "test position" do |*examples|
      context "with after" do
        it_behaves_like *examples do
          let(:position) {" after test_name"}
          let(:position_hash){
            { after: "test_name" }
          }
        end
      end
      context "with first" do
        it_behaves_like *examples do
          let(:position) {" first"}
          let(:position_hash){
            { position: :first }
          }
        end
      end
      context "with none" do
        it_behaves_like *examples do
          let(:position) {""}
          let(:position_hash){
            {}
          }
        end
      end
    end
    shared_examples "test not null" do |*examples|
      context "with not null option" do
        it_behaves_like *examples do
          let(:not_null) {" not null"}
          let(:not_null_hash){
            { not_null: true }
          }
        end
      end
      context "without not null option" do
        it_behaves_like *examples do
          let(:not_null) {""}
          let(:not_null_hash){
            {}
          }
        end
      end
    end
    shared_examples "test default for timestamp" do |*examples|
      context "timestamp" do
        it_behaves_like *examples do
          let(:default) {" default current_timestamp"}
          let(:default_hash){
            { default: "current_timestamp" }
          }
        end
      end
      context "timestamp" do
        it_behaves_like *examples do
          let(:default) {" default localtime"}
          let(:default_hash){
            { default: "current_timestamp" }
          }
        end
      end
      context "none" do
        it_behaves_like *examples do
          let(:default) {""}
          let(:default_hash){
            {}
          }
        end
      end
    end
    shared_examples "test default for varchar" do |*examples|
      context "null" do
        it_behaves_like *examples do
          let(:default) {" default NULL"}
          let(:default_hash){
            { default: nil }
          }
        end
      end
      context "empty string" do
        it_behaves_like *examples do
          let(:default) {" default ''"}
          let(:default_hash){
            { default: "" }
          }
        end
      end
      context "string with spaces" do
        it_behaves_like *examples do
          let(:default) {" default '0 0 0 0 0 0'"}
          let(:default_hash){
            { default: "0 0 0 0 0 0" }
          }
        end
      end
      context "none" do
        it_behaves_like *examples do
          let(:default) {""}
          let(:default_hash){
            {}
          }
        end
      end
    end
    shared_examples "test auto increment" do |*examples|
      context "with auto_increment" do
        it_behaves_like *examples do
          let(:auto_increment) {" auto_increment"}
          let(:auto_increment_hash){
            { auto_increment: true }
          }
        end
      end
      context "without auto_increment" do
        it_behaves_like *examples do
          let(:auto_increment) {""}
          let(:auto_increment_hash){
            {}
          }
        end
      end
    end
    shared_examples "test comment" do |*examples|
      context "with a comment" do
        it_behaves_like *examples do
          let(:comment) {" COMMENT 'Hello World!'"}
        end
      end
      context "with a double quoted comment" do
        it_behaves_like *examples do
          let(:comment) {%q| comment "Hello World!"|}
        end
      end
      context "with a backslash inside double quotes" do
        it_behaves_like *examples do
          let(:comment) {%q| comment "\\\\"|}
        end
      end
      context "with special characters" do
        it_behaves_like *examples do
          let(:comment) {%q| comment "https://flydata.com $ \\\\'\"\n\t"|}
        end
      end
      context "without a comment" do
        it_behaves_like *examples do
          let(:comment) {""}
        end
      end
    end
    shared_examples "test unique" do |*examples|
      context "with unique" do
        it_behaves_like *examples do
          let(:unique) {" UNIQUE"}
          let(:unique_hash){
            { unique: true }
          }
        end
      end
      context "without unique" do
        it_behaves_like *examples do
          let(:unique) {""}
          let(:unique_hash){
            {}
          }
        end
      end
    end
    shared_examples "test column definition" do |*examples|
      context "varchar" do
        it_behaves_like "test not null", "test default for varchar", "test comment", *examples do
          let(:col_def) {"varchar(256)#{not_null}#{default}#{comment}"}
          let(:col_def_hash) {
            { type: "varchar(768)" }.merge!(not_null_hash).merge!(default_hash)
          }
        end
      end
      context "timestamp" do
        it_behaves_like "test not null", "test default for timestamp", *examples do
          let(:col_def) {"timestamp#{not_null}#{default}"}
          let(:col_def_hash) {
            { type: "datetime" }.merge!(not_null_hash).merge!(default_hash)
          }
        end
      end
      context "integer" do
        it_behaves_like "test not null", "test auto increment", "test comment", *examples do
          let(:col_def) {"int(11)#{not_null}#{auto_increment}#{comment}"}
          let(:col_def_hash) {
            { type: "int4(11)" }.merge!(not_null_hash).merge!(auto_increment_hash)
          }
        end
      end
      context "decimal" do
        it_behaves_like "test not null", "test unique", *examples do
          let(:col_def) {"decimal(10,2)#{not_null}#{unique}"}
          let(:col_def_hash) {
            { type: "numeric(10,2)" }.merge!(not_null_hash).merge!(unique_hash)
          }
        end
      end
    end
    shared_examples "test parser parsing a change column" do
      let(:action_hash) {
        change_action_hash.merge!({
          action: :change_column,
          query: alter_table_action
        })
      }
      it_behaves_like "a parser parsing a single action alter table query"
    end
    context 'change column' do
      context 'change column name' do
        let(:alter_table_action) { "change#{column} name name1 #{col_def}#{position}" }
        let(:change_action_hash) {
          {
            old_column: "name",
            column: "name1",
          }.merge!(position_hash).merge!(col_def_hash)
        }
        it_behaves_like "test optional column", "test column definition", "test position", "test parser parsing a change column"
      end
      context 'no change to column name' do
        let(:alter_table_action) { "change#{column} name1 name1 #{col_def}#{position}" }
        let(:change_action_hash) {
          {
            old_column: "name1",
            column: "name1",
          }.merge!(position_hash).merge!(col_def_hash)
        }
        it_behaves_like "test optional column", "test column definition", "test position", "test parser parsing a change column"
      end
    end
    context 'modify column' do
      let(:alter_table_action) { "modify#{column} name1 #{col_def}#{position}" }
      let(:change_action_hash) {
        {
          old_column: "name1",
          column: "name1",
        }.merge!(position_hash).merge!(col_def_hash)
      }
      it_behaves_like "test optional column", "test column definition", "test position", "test parser parsing a change column"
    end
    context 'algorithm and lock option' do
      ["ALGORITHM", "LOCK"].each do |op|
        context "#{op}" do
          let(:action) { op.downcase.to_sym }
          context "with default #{op}" do
            let(:alter_table_action) { "#{op}#{equal} DEFAULT" }
            it_behaves_like "test optional equal", "a parser parsing a nonbreaking query"
          end
          context "with any #{op}" do
            let(:alter_table_action) { "#{op.downcase}#{equal} #{ident}" }
            it_behaves_like "test optional equal", "test identifier", "a parser parsing a nonbreaking query"
          end
          context "without spaces between eq and #{op}" do
            let(:alter_table_action) { "#{op}=#{ident}" }
            it_behaves_like "test identifier", "a parser parsing a nonbreaking query"
          end
        end
      end
    end
    context 'alter column' do
      let(:action) { :alter_column }
      context 'set default' do
        let(:alter_table_action) { "alter#{column} #{ident} set DEFAULT #{signed_literal}" }
        it_behaves_like "test optional column", "test field identifier", "test signed literal", "a parser parsing a nonbreaking query"
      end
      context 'drop default' do
        let(:alter_table_action) { "alter#{column} #{ident} DROP default" }
        it_behaves_like "test optional column", "test field identifier", "a parser parsing a nonbreaking query"
      end
    end
  end
end