Adds support for per = 0

.envrc

@@ -0,0 +1,7 @@
+# A direnv config file: https://github.com/direnv/direnv
+
+if [ "$(type -t direnv_load)" = 'function' ]; then
+  # Whatever you want only direnv to execute
+  PATH_add bin
+fi
+

.gitignore

@@ -1,4 +1,6 @@
 coverage
 rdoc
 pkg
-log/test.log
+log/test.log
+.rspec.status
+.rake_t_cache

.tm_properties

@@ -0,0 +1 @@
+excludeDirectories = "{coverage,log,vendor,arena,}"

README.md

@@ -50,15 +50,11 @@ gives you the following options:
 
 Note: whenever you run a query `simple-sql` takes care of sending query parameters over the wire properly. That means that you use placeholders `$1`, `$2`, etc. to use these inside your queries; the following is a correct example:
 
-```ruby
-Simple::SQL.all "SELECT * FROM users WHERE email=$1", "[email protected]"
-```
+    Simple::SQL.all "SELECT * FROM users WHERE email=$1", "[email protected]"
 
 Also note that it is not possible to use an array as the argument for the `IN(?)` SQL construct. Instead you want to use `ANY`, for example:
 
-```ruby
-Simple::SQL.all "SELECT * FROM users WHERE id = ANY($1)", [1,2,3]
-```
+    Simple::SQL.all "SELECT * FROM users WHERE id = ANY($1)", [1,2,3]
 
 ### Simple::SQL.all: Fetching all results of a query
 
@@ -71,18 +67,14 @@ Otherwise it returns an array of arrays.
 
 Examples:
 
-```ruby
-Simple::SQL.all("SELECT id FROM users")        # returns an array of id values, but
-Simple::SQL.all("SELECT id, email FROM users") # returns an array of arrays `[ <id>, <email> ]`.
-```
+    Simple::SQL.all("SELECT id FROM users")        # returns an array of id values, but
+    Simple::SQL.all("SELECT id, email FROM users") # returns an array of arrays `[ <id>, <email> ]`.
 
 If a block is passed to SQL.all, each row is yielded into the block:
 
-```ruby
-Simple::SQL.all "SELECT id, email FROM users" do |id, email|
-  # do something
-end
-```
+    Simple::SQL.all "SELECT id, email FROM users" do |id, email|
+      # do something
+    end
 
 ### Simple::SQL.ask:  getting the first result
 
@@ -94,10 +86,8 @@ If the SQL query returns rows with one column, this method returns the column va
 
 Examples:
 
-```ruby
-Simple::SQL.ask "SELECT id FROM users WHERE email=$1", "foo@local"         # returns a number (or `nil`) and
-Simple::SQL.ask "SELECT id, email FROM users WHERE email=$?", "foo@local"  # returns an array `[ <id>, <email> ]` (or `nil`)
-```
+    Simple::SQL.ask "SELECT id FROM users WHERE email=$1", "foo@local"         # returns a number (or `nil`) and
+    Simple::SQL.ask "SELECT id, email FROM users WHERE email=$?", "foo@local"  # returns an array `[ <id>, <email> ]` (or `nil`)
 
 ### Simple::SQL.ask/Simple::SQL.all:  fetching hashes
 
@@ -111,15 +101,15 @@ If you want the returned record to be in a structure which is not a Hash, you ca
 the `into: <klass>` option. The following would return an array of up to two `OpenStruct`
 objects:
 
-    sql = "SELECT id, email FROM users WHERE id = ANY($1) LIMIT 1", 
+    sql = "SELECT id, email FROM users WHERE id = ANY($1) LIMIT 1"
     Simple::SQL.all sql, [1,2,3], into: OpenStruct
 
-This supports all target types that take a contructor which acceps Hash arguments.
+This supports all target types that take a constructor which accepts Hash arguments.
 
 It also supports a :struct argument, in which case simple-sql creates uses a Struct-class.
 Struct classes are reused when possible, and are maintained by Simple::SQL. 
 
-    sql = "SELECT id, email FROM users WHERE id = ANY($1) LIMIT 1", 
+    sql = "SELECT id, email FROM users WHERE id = ANY($1) LIMIT 1"
     Simple::SQL.all sql, [1,2,3], into: :struct
 
 ### Transaction support

Rakefile

@@ -10,3 +10,8 @@ task default: "test:prepare_db" do
   sh "USE_ACTIVE_RECORD=1 rspec"
   sh "rubocop -D"
 end
+
+task :fastspec do
+  sh "SKIP_SIMPLE_COV=1 rspec --only-failures"
+  sh "rspec"
+end

lib/simple/sql/connection_adapter.rb

@@ -64,10 +64,9 @@ def ask(sql, *args, into: nil)
 
   def add_page_info(scope, results)
     raise ArgumentError, "expect Array but get a #{results.class.name}" unless results.is_a?(Array)
-    raise ArgumentError, "per must be > 0" unless scope.per > 0
 
     # optimization: add empty case (page <= 1 && results.empty?)
-    if scope.page <= 1 && results.empty?
+    if scope.page <= 1 && scope.per > 0 && results.empty?
       Scope::PageInfo.attach(results, total_count: 0, per: scope.per, page: 1)
     else
       sql = "SELECT COUNT(*) FROM (#{scope.order_by(nil).to_sql(pagination: false)}) simple_sql_count"
@@ -80,6 +79,8 @@ def exec_logged(sql_or_scope, *args)
     if sql_or_scope.is_a?(Scope)
       raise ArgumentError, "You cannot call .all with a scope and additional arguments" unless args.empty?
 
+      return [] if sql_or_scope.per == 0
+
       sql  = sql_or_scope.to_sql
       args = sql_or_scope.args
     else
@@ -92,6 +93,8 @@ def exec_logged(sql_or_scope, *args)
   end
 
   def enumerate(result, into:, &block)
+    return result if result.is_a?(Array) && result.empty?
+
     decoder = Decoder.new(self, result, into: into)
 
     if block

lib/simple/sql/scope.rb

@@ -52,6 +52,17 @@ def where(sql_fragment, arg = :__dummy__no__arg, placeholder: "?")
     duplicate.send(:where!, sql_fragment, arg, placeholder: placeholder)
   end
 
+  # Set pagination
+  def paginate(per:, page: 1)
+    duplicate.send(:paginate!, per: per, page: page)
+  end
+
+  def order_by(sql_fragment)
+    duplicate.send(:order_by!, sql_fragment)
+  end
+
+  private
+
   def where!(sql_fragment, arg = :__dummy__no__arg, placeholder: "?")
     if arg == :__dummy__no__arg
       @filters << sql_fragment
@@ -63,11 +74,6 @@ def where!(sql_fragment, arg = :__dummy__no__arg, placeholder: "?")
     self
   end
 
-  # Set pagination
-  def paginate(per:, page:)
-    duplicate.send(:paginate!, per: per, page: page)
-  end
-
   def paginate!(per:, page:)
     @per = per
     @page = page
@@ -81,10 +87,6 @@ def order_by!(sql_fragment)
     self
   end
 
-  def order_by(sql_fragment)
-    duplicate.order_by!(sql_fragment)
-  end
-
   public
 
   # Is this a paginated scope?
@@ -124,7 +126,7 @@ module PageInfo
     def self.attach(results, total_count:, per:, page:)
       results.extend(self)
       results.instance_variable_set :@total_count, total_count
-      results.instance_variable_set :@total_pages, (total_count + (per - 1)) / per
+      results.instance_variable_set :@total_pages, per > 0 ? (total_count + (per - 1)) / per : -1
       results.instance_variable_set :@current_page, page
       results
     end

scripts/watch

@@ -1,2 +1,2 @@
 #!/bin/bash
-watchr lib,spec rspec
+watchr lib,spec rake fastspec

spec/simple/sql_scope_spec.rb

@@ -140,6 +140,18 @@ def expects(expected_result, sql, *args)
       end
     end
 
+    context "with per=0" do
+      let(:result) { SQL.all(scope.paginate(per: 0)) }
+
+      it "returns an empty result set" do
+        expect(result).to eq([])
+      end
+
+      it "adds total_count info to the .all return value" do
+        expect(result.total_count).to eq(2)
+      end
+    end
+
     context "with per=2" do
       it "returns an empty array after the last page" do
         result = SQL.all(scope.paginate(per: 2, page: 2))

spec/spec_helper.rb

@@ -23,6 +23,8 @@
 ActiveRecord::Base.logger.level = Logger::INFO
 
 RSpec.configure do |config|
+  config.example_status_persistence_file_path = ".rspec.status"
+
   config.run_all_when_everything_filtered = true
   config.filter_run focus: (ENV["CI"] != "true")
   config.expect_with(:rspec) { |c| c.syntax = :expect }

spec/support/004_simplecov.rb

@@ -1,3 +1,5 @@
+unless ENV['SKIP_SIMPLE_COV']
+
 require "simplecov"
 
 # make sure multiple runs result in multiple result set. SimpleCov will take
@@ -12,3 +14,5 @@
 
   minimum_coverage 90
 end
+
+end