Not adding parentheses where not needed.

lib/pg_query/deparse.rb

@@ -39,7 +39,7 @@ def deparse_item(item, context = nil) # rubocop:disable Metrics/CyclomaticComple
  when 'AEXPR OR'
  deparse_aexpr_or(node)
  when 'AEXPR'
- deparse_aexpr(node)
+ deparse_aexpr(node, context)
  when 'ALIAS'
  deparse_alias(node)
  when 'ALTER TABLE'
@@ -248,7 +248,8 @@ def deparse_funccall(node)
  # COUNT(*)
  args << '*' if node['agg_star']
 
- output << format('%s(%s)', node['funcname'].join('.'), args.join(', '))
+ name = (node['funcname'] - ['pg_catalog']).join('.')
+ output << format('%s(%s)', name, args.join(', '))
  output << format('OVER (%s)', deparse_item(node['over'])) if node['over']
 
  output.join(' ')
@@ -295,11 +296,16 @@ def deparse_range_function(node)
  output.join(' ')
  end
 
- def deparse_aexpr(node)
+ def deparse_aexpr(node, context = false)
  output = []
- output << deparse_item(node['lexpr'])
- output << deparse_item(node['rexpr'])
- output.join(' ' + node['name'][0] + ' ')
+ output << deparse_item(node['lexpr'], context || true)
+ output << deparse_item(node['rexpr'], context || true)
+ output = output.join(' ' + node['name'][0] + ' ')
+ if context
+ # This is a nested expression, add parentheses.
+ output = '(' + output + ')'
+ end
+ output
  end
 
  def deparse_aexpr_and(node)
@@ -422,7 +428,12 @@ def deparse_constraint(node)
  # NOT_NULL -> NOT NULL
  output << node['contype'].gsub('_', ' ')
 
- output << '(' + deparse_item(node['raw_expr']) + ')' if node['raw_expr']
+ if node['raw_expr']
+ expression = deparse_item(node['raw_expr'])
+ # Unless it's simple, put parentheses around it
+ expression = '(' + expression + ')' if node['raw_expr'].keys == ['AEXPR']
+ output << expression
+ end
  output << '(' + node['keys'].join(', ') + ')' if node['keys']
  output << "USING INDEX #{node['indexname']}" if node['indexname']
  output.join(' ')

spec/lib/pg_query/deparse_spec.rb

@@ -263,6 +263,22 @@
  end
  it { is_expected.to eq oneline_query }
  end
+
+ context 'from generated sequence' do
+ let(:query) do
+ """
+ INSERT INTO jackdanger_card_totals (id, amount_cents, created_at)
+ SELECT
+ series.i,
+ random() * 1000,
+ (SELECT
+ '2015-08-25 00:00:00 -0700'::timestamp +
+ (('2015-08-25 23:59:59 -0700'::timestamp - '2015-08-25 00:00:00 -0700'::timestamp) * random()))
+ FROM generate_series(1, 10000) series(i);
+ """
+ end
+ it { is_expected.to eq oneline_query }
+ end
  end
 
  context 'DELETE' do
@@ -326,11 +342,11 @@
  let(:query) do
  """
  CREATE TABLE distributors (
- name varchar(40) DEFAULT ('Luso Films'),
+ name varchar(40) DEFAULT 'Luso Films',
  len interval hour to second(3),
- name varchar(40) DEFAULT ('Luso Films'),
- did int DEFAULT (nextval('distributors_serial')),
- stamp timestamp DEFAULT (pg_catalog.now()) NOT NULL,
+ name varchar(40) DEFAULT 'Luso Films',
+ did int DEFAULT nextval('distributors_serial'),
+ stamp timestamp DEFAULT now() NOT NULL,
  stamptz timestamp with time zone,
  time time NOT NULL,
  timetz time with time zone,
@@ -358,7 +374,7 @@
  let(:query) do
  """
  CREATE TABLE tablename (
- colname int NOT NULL DEFAULT (nextval('tablename_colname_seq'))
+ colname int NOT NULL DEFAULT nextval('tablename_colname_seq')
  );
  """
  end
@@ -399,7 +415,7 @@
  ADD CONSTRAINT zipchk CHECK (char_length(zipcode) = 5),
  ALTER COLUMN tstamp DROP DEFAULT,
  ALTER COLUMN tstamp TYPE timestamp with time zone
- USING 'epoch'::timestamp with time zone + pg_catalog.date_part('epoch', tstamp) * '1 second'::interval,
+ USING 'epoch'::timestamp with time zone + (date_part('epoch', tstamp) * '1 second'::interval),
  ALTER COLUMN tstamp SET DEFAULT now(),
  ALTER COLUMN tstamp DROP DEFAULT,
  ALTER COLUMN tstamp SET STATISTICS -5,