Add StatementAppender

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## [Unreleased]
 
+- Introduce StatementAppender for better spacing between statements
+
 ## [0.2.1] - 2025-02-15
 
 - Add transform to remove SET commands with default values

README.md

@@ -191,8 +191,6 @@ INSERT INTO "schema_migrations" (version) VALUES
 into this normalize (and much more compatch & readable) version:
 
 ```sql
-
-
 CREATE EXTENSION IF NOT EXISTS pgcrypto SCHEMA public;
 
 

lib/activerecord-pg-format-db-structure.rb

@@ -3,6 +3,7 @@
 require_relative "activerecord-pg-format-db-structure/version"
 
 require_relative "activerecord-pg-format-db-structure/deparser"
+require_relative "activerecord-pg-format-db-structure/statement_appender"
 require_relative "activerecord-pg-format-db-structure/transforms/remove_comments_on_extensions"
 require_relative "activerecord-pg-format-db-structure/transforms/inline_serials"
 require_relative "activerecord-pg-format-db-structure/transforms/inline_primary_keys"
@@ -29,6 +30,7 @@ module ActiveRecordPgFormatDbStructure
   ].freeze
 
   DEFAULT_DEPARSER = Deparser
+  DEFAULT_STATEMENT_APPENDER = StatementAppender
 end
 
 # :nocov:

lib/activerecord-pg-format-db-structure/deparser.rb

@@ -32,42 +32,42 @@ def deparse_raw_statement(raw_statement)
     private
 
     def deparse_stmt_generic(stmt)
-      generic_str = +"\n\n"
+      generic_str = +""
       generic_str << deparse_stmt_and_indent(stmt)
       generic_str << ";"
       generic_str
     end
 
     def deparse_stmt_compact(stmt)
-      compact_str = +"\n"
+      compact_str = +""
       compact_str << deparse_stmt(stmt)
       compact_str << ";"
       compact_str
     end
 
     def deparse_insert_stmt(stmt)
-      insert_str = +"\n\n\n"
+      insert_str = +""
       insert_str << deparse_stmt_and_indent(stmt)
       insert_str << "\n;"
       insert_str
     end
 
     def deparse_create_stmt(stmt)
-      table_str = "\n\n\n-- Name: #{stmt.relation.relname}; Type: TABLE;\n\n"
+      table_str = "-- Name: #{stmt.relation.relname}; Type: TABLE;\n\n"
       table_str << deparse_stmt_and_indent(stmt)
       table_str << ";"
       table_str
     end
 
     def deparse_view_stmt(stmt)
-      table_str = "\n\n\n-- Name: #{stmt.view.relname}; Type: VIEW;\n\n"
+      table_str = "-- Name: #{stmt.view.relname}; Type: VIEW;\n\n"
       table_str << deparse_stmt_and_indent(stmt)
       table_str << ";"
       table_str
     end
 
     def deparse_create_table_as_stmt(stmt)
-      table_str = "\n\n\n-- Name: #{stmt.into.rel.relname}; Type: MATERIALIZED VIEW;\n\n"
+      table_str = "-- Name: #{stmt.into.rel.relname}; Type: MATERIALIZED VIEW;\n\n"
       table_str << deparse_stmt_and_indent(stmt)
 
       # couldn't find a better solution for this, but probably an OK workaround?

lib/activerecord-pg-format-db-structure/formatter.rb

@@ -6,14 +6,16 @@
 module ActiveRecordPgFormatDbStructure
   # Formats & normalizes in place the given SQL string
   class Formatter
-    attr_reader :transforms, :deparser
+    attr_reader :transforms, :deparser, :statement_appender
 
     def initialize(
       transforms: DEFAULT_TRANSFORMS,
-      deparser: DEFAULT_DEPARSER
+      deparser: DEFAULT_DEPARSER,
+      statement_appender: DEFAULT_STATEMENT_APPENDER
     )
       @transforms = transforms
       @deparser = deparser
+      @statement_appender = statement_appender
     end
 
     def format(source)
@@ -23,9 +25,17 @@ def format(source)
         transform.new(raw_statements).transform!
       end
 
-      raw_statements.map do |raw_statement|
-        deparser.new(source).deparse_raw_statement(raw_statement)
-      end.compact.join
+      appender = statement_appender.new
+      raw_statements.each do |raw_statement|
+        statement = deparser.new(source).deparse_raw_statement(raw_statement)
+        appender.append_statement!(
+          statement,
+          statement_kind: PgQuery::Node.inner_class_to_name(
+            raw_statement.stmt.inner.class
+          )
+        )
+      end
+      appender.output
     end
   end
 end

lib/activerecord-pg-format-db-structure/railtie.rb

@@ -6,6 +6,7 @@ class Railtie < Rails::Railtie
     config.activerecord_pg_format_db_structure = ActiveSupport::OrderedOptions.new
     config.activerecord_pg_format_db_structure.transforms = DEFAULT_TRANSFORMS.dup
     config.activerecord_pg_format_db_structure.deparser = DEFAULT_DEPARSER
+    config.activerecord_pg_format_db_structure.statement_appender = DEFAULT_STATEMENT_APPENDER
 
     rake_tasks do
       load "activerecord-pg-format-db-structure/tasks/clean_db_structure.rake"

lib/activerecord-pg-format-db-structure/statement_appender.rb

@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+require "pg_query"
+require_relative "indenter"
+
+module ActiveRecordPgFormatDbStructure
+  # Appends statements with reasonable spacing in-between
+  class StatementAppender
+    attr_reader :output
+
+    def initialize(output = +"")
+      @output = output
+      @previous_statement_kind = nil
+    end
+
+    def append_statement!(statement, statement_kind:)
+      output.chomp!
+      output << newlines_separator(
+        previous_kind: @previous_statement_kind,
+        current_kind: statement_kind
+      )
+      @previous_statement_kind = statement_kind
+      output << statement
+      output << "\n"
+    end
+
+    private
+
+    def newlines_separator(previous_kind:, current_kind:)
+      case [
+        previous_kind,
+        current_kind
+      ]
+      in [
+        nil,
+        _
+      ]
+        ""
+      in [
+        _,
+        :insert_stmt | :create_stmt | :view_stmt | :create_table_as_stmt
+      ]
+        "\n\n\n"
+      in [
+        :create_stmt | :view_stmt | :create_table_as_stmt | :index_stmt,
+        :index_stmt
+      ] | [
+        :variable_set_stmt,
+        :variable_set_stmt
+      ]
+        "\n"
+      else
+        "\n\n"
+      end
+    end
+  end
+end

spec/activerecord-pg-format-db-structure/deparser_spec.rb

@@ -15,9 +15,7 @@
           SELECT * FROM my_table WHERE 1 = 1;
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           SELECT *
           FROM my_table
           WHERE 1 = 1;
@@ -29,9 +27,7 @@
           SELECT '1'::integer;
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           SELECT '1'::int;
         SQL
       end
@@ -48,9 +44,7 @@
           WHERE bar > 10 OR bar < 5 OR (bar < 2 AND baz);
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           SELECT sum(foo) AS column_a,
                  CASE
                    WHEN foo = 'a' THEN 1
@@ -71,10 +65,7 @@
           INSERT INTO schema_migrations (version) VALUES ('20250124155339'), ('20250134155339') , ('20250144155339');
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           INSERT INTO schema_migrations (version) VALUES
             ('20250124155339')
           , ('20250134155339')
@@ -89,10 +80,7 @@
 
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           INSERT INTO schema_migrations (version)
           SELECT foo
           FROM bar
@@ -107,8 +95,7 @@
           CREATE UNIQUE INDEX only_one_pending_per_comment_id ON public.my_table USING btree (comment_id) WHERE pending;
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           CREATE UNIQUE INDEX only_one_pending_per_comment_id ON public.my_table USING btree (comment_id) WHERE pending;
         SQL
       end
@@ -122,10 +109,7 @@
           );
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           -- Name: post_stats; Type: VIEW;
 
           CREATE VIEW public.post_stats AS
@@ -141,10 +125,7 @@
           );
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           -- Name: post_stats; Type: VIEW;
 
           CREATE VIEW public.post_stats AS
@@ -160,9 +141,7 @@
           SELECT * from my_cte;
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           WITH my_cte AS (
               SELECT foo,
                      baz
@@ -182,10 +161,7 @@
           );
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           -- Name: post_stats; Type: MATERIALIZED VIEW;
 
           CREATE MATERIALIZED VIEW public.post_stats AS
@@ -201,10 +177,7 @@
           ) WITH NO DATA;
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           -- Name: post_stats; Type: MATERIALIZED VIEW;
 
           CREATE MATERIALIZED VIEW public.post_stats AS
@@ -250,10 +223,7 @@
               ) main_status;
         SQL
 
-        expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+        expect(formatter.format(source)).to eq(<<~SQL)
           -- Name: my_bigg_aggregated_view; Type: VIEW;
 
           CREATE VIEW public.my_bigg_aggregated_view AS

spec/activerecord-pg-format-db-structure/formatter_spec.rb

@@ -178,17 +178,13 @@
         ('20250124155339');
       SQL
 
-      expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
+      expect(formatter.format(source)).to eq(<<~SQL)
         SET client_encoding TO "UTF8";
 
         SELECT pg_catalog.set_config('search_path', '', false);
 
         SET check_function_bodies TO TRUE;
-
         SET client_min_messages TO warning;
-
         SET row_security TO OFF;
 
         CREATE EXTENSION IF NOT EXISTS pgcrypto SCHEMA public;

spec/activerecord-pg-format-db-structure/transforms/group_alter_table_statements_spec.rb

@@ -56,10 +56,7 @@
         ('20250124155339');
       SQL
 
-      expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+      expect(formatter.format(source)).to eq(<<~SQL)
         -- Name: comments; Type: TABLE;
 
         CREATE TABLE public.comments (
@@ -143,10 +140,7 @@
         ('20250124155339');
       SQL
 
-      expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+      expect(formatter.format(source)).to eq(<<~SQL)
         -- Name: comments; Type: TABLE;
 
         CREATE TABLE public.comments (

spec/activerecord-pg-format-db-structure/transforms/inline_constraints_spec.rb

@@ -50,10 +50,7 @@
         ('20250124155339');
       SQL
 
-      expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+      expect(formatter.format(source)).to eq(<<~SQL)
         -- Name: comments; Type: TABLE;
 
         CREATE TABLE public.comments (

spec/activerecord-pg-format-db-structure/transforms/inline_foreign_keys_spec.rb

@@ -50,10 +50,7 @@
         ('20250124155339');
       SQL
 
-      expect(formatter.format(source)).to eq(<<~SQL.chomp)
-
-
-
+      expect(formatter.format(source)).to eq(<<~SQL)
         -- Name: comments; Type: TABLE;
 
         CREATE TABLE public.comments (