Implement function criteria (#912)

* Add updated? and created? methods on SaveOperations

Implements #888.
Adds two new boolean methods to SaveOperation.
They work similarly to new_record? but always return false if the
record was not persisted (e.g: failed save or not-yet-performed
operation)

* Implement date function

* Move upper and lower to new criterias

* generalize the application of functions to columns

* Put in standby the extra-param function creation

* Final clean up

spec/avram/string_criteria_spec.cr

@@ -33,6 +33,12 @@ describe String::Lucky::Criteria do
     end
   end
 
+  describe "trim" do
+    it "uses TRIM" do
+      name.trim.eq("elon").to_sql.should eq ["SELECT #{QueryMe::COLUMN_SQL} FROM users WHERE TRIM(users.name) = $1", "elon"]
+    end
+  end
+
   describe "not" do
     describe "with chained criteria" do
       it "negates the following criteria" do

spec/avram/time_criteria_spec.cr

@@ -14,6 +14,11 @@ describe Time::Lucky::Criteria do
     end
   end
 
+  it "as_date" do
+    input_date = "2012-01-31"
+    activated_at.as_date.eq(input_date).to_sql.should eq ["SELECT users.id, users.created_at, users.updated_at, users.activated_at FROM users WHERE DATE(users.activated_at) = $1", input_date]
+  end
+
   describe "extract" do
     it "fails with non supported symbol" do
       expect_raises(ArgumentError) { activated_at.extract(:dayz).eq(5).to_sql }

src/avram/charms/string_extensions.cr

@@ -29,8 +29,6 @@ class String
 
     class Criteria(T, V) < Avram::Criteria(T, V)
       include Avram::IncludesCriteria(T, V)
-      @upper = false
-      @lower = false
 
       def like(value : String) : T
         add_clause(Avram::Where::Like.new(column, value))
@@ -40,25 +38,9 @@ class String
         add_clause(Avram::Where::Ilike.new(column, value))
       end
 
-      def upper
-        @upper = true
-        self
-      end
-
-      def lower
-        @lower = true
-        self
-      end
-
-      def column
-        if @upper
-          "UPPER(#{@column})"
-        elsif @lower
-          "LOWER(#{@column})"
-        else
-          @column
-        end
-      end
+      define_function_criteria(upper, V)
+      define_function_criteria(lower, V)
+      define_function_criteria(trim, String)
     end
   end
 end

src/avram/charms/time_extensions.cr

@@ -78,6 +78,8 @@ struct Time
     class Criteria(T, V) < Avram::Criteria(T, V)
       include Avram::BetweenCriteria(T, V)
       include Avram::ExtractCriteria
+
+      define_function_criteria(as_date, String, "DATE")
     end
   end
 end

src/avram/criteria.cr

@@ -185,4 +185,11 @@ class Avram::Criteria(T, V)
       sql_clause
     end
   end
+
+  macro define_function_criteria(name, output_type = V, sql_name = nil)
+    {% sql_name = sql_name ? sql_name.id : name.id.upcase %}
+      def {{name}}
+        Criteria(T,{{output_type}}).new(rows, "{{sql_name}}(#{column})")
+      end
+  end
 end

src/avram/criteria_extensions/between_criteria.cr

@@ -4,7 +4,7 @@ module Avram::BetweenCriteria(T, V)
     def between(low_value : V, high_value : V)
       add_clauses([
         Avram::Where::GreaterThanOrEqualTo.new(@column, V.adapter.to_db!(low_value)),
-        Avram::Where::LessThanOrEqualTo.new(@column, V.adapter.to_db!(high_value))
+        Avram::Where::LessThanOrEqualTo.new(@column, V.adapter.to_db!(high_value)),
       ])
     end
   end

src/avram/define_attribute.cr

@@ -20,7 +20,6 @@ module Avram::DefineAttribute
       ATTRIBUTES = [] of Nil
     \{% end %}
 
-
     \{% if !@type.ancestors.first.abstract? %}
       \{% for attribute in @type.ancestors.first.constant :ATTRIBUTES %}
         \{% ATTRIBUTES << attribute %}

src/avram/model.cr

@@ -16,7 +16,7 @@ abstract class Avram::Model
   end
 
   macro inherited
-    COLUMNS = [] of Nil # types are not checked in macros
+    COLUMNS      = [] of Nil # types are not checked in macros
     ASSOCIATIONS = [] of Nil # types are not checked in macros
     include LuckyCache::Cachable
   end