Merge pull request #20 from B-CDD/feature/and_expose_must_halt_by_def…

…ault Make `BCDD::Result::Context::Success#and_expose()` to produce a halted success by default
solid-process · Dec 12, 2023 · 913eeca · 913eeca
2 parents 40d98d8 + bb3e942
commit 913eeca
Show file tree

Hide file tree

Showing 8 changed files with 132 additions and 21 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,22 +1,24 @@
 - [\[Unreleased\]](#unreleased)
+  - [Changed](#changed)
+  - [Fixed](#fixed)
 - [\[0.9.0\] - 2023-12-12](#090---2023-12-12)
   - [Added](#added)
-  - [Changed](#changed)
+  - [Changed](#changed-1)
 - [\[0.8.0\] - 2023-12-11](#080---2023-12-11)
   - [Added](#added-1)
-  - [Changed](#changed-1)
+  - [Changed](#changed-2)
   - [Removed](#removed)
 - [\[0.7.0\] - 2023-10-27](#070---2023-10-27)
   - [Added](#added-2)
-  - [Changed](#changed-2)
+  - [Changed](#changed-3)
 - [\[0.6.0\] - 2023-10-11](#060---2023-10-11)
   - [Added](#added-3)
-  - [Changed](#changed-3)
+  - [Changed](#changed-4)
 - [\[0.5.0\] - 2023-10-09](#050---2023-10-09)
   - [Added](#added-4)
 - [\[0.4.0\] - 2023-09-28](#040---2023-09-28)
   - [Added](#added-5)
-  - [Changed](#changed-4)
+  - [Changed](#changed-5)
   - [Removed](#removed-1)
 - [\[0.3.0\] - 2023-09-26](#030---2023-09-26)
   - [Added](#added-6)
@@ -28,6 +30,14 @@
 
 ## [Unreleased]
 
+### Changed
+
+- **(BREAKING)** Make `BCDD::Result::Context::Success#and_expose()` to produce a halted success by default. You can turn this off by passing `halted: false`.
+
+### Fixed
+
+- Make `BCDD::Result::Context#and_then(&block)` accumulate the result value.
+
 ## [0.9.0] - 2023-12-12
 
 ### Added

diff --git a/README.md b/README.md
@@ -1569,6 +1569,8 @@ Divide.new.call(10, 5)
 #<BCDD::Result::Context::Success type=:ok value={:number=>2, :number1=>10, :number2=>5}>
 ```
 
+> PS: The `#and_expose` produces a halted success by default. This means the next step will not be executed even if you call `#and_then` after `#and_expose`. To change this behavior, you can pass `halted: false` to `#and_expose`.
+
 <p align="right"><a href="#-bcddresult">⬆️ &nbsp;back to top</a></p>
 
 ##### Module example (Singleton Methods)

diff --git a/lib/bcdd/result.rb b/lib/bcdd/result.rb
@@ -84,16 +84,12 @@ def on_unknown
     tap { yield(value, type) if unknown }
   end
 
-  def and_then(method_name = nil, context = nil)
+  def and_then(method_name = nil, context = nil, &block)
     return self if halted?
 
-    method_name && block_given? and raise ::ArgumentError, 'method_name and block are mutually exclusive'
+    method_name && block and raise ::ArgumentError, 'method_name and block are mutually exclusive'
 
-    return call_subject_method(method_name, context) if method_name
-
-    result = yield(value)
-
-    ensure_result_object(result, origin: :block)
+    method_name ? call_and_then_subject_method(method_name, context) : call_and_then_block(block)
   end
 
   def handle
@@ -139,7 +135,7 @@ def known(block)
     block.call(value, type)
   end
 
-  def call_subject_method(method_name, context)
+  def call_and_then_subject_method(method_name, context)
     method = subject.method(method_name)
 
     result =
@@ -153,6 +149,16 @@ def call_subject_method(method_name, context)
     ensure_result_object(result, origin: :method)
   end
 
+  def call_and_then_block(block)
+    call_and_then_block!(block, value)
+  end
+
+  def call_and_then_block!(block, value)
+    result = block.call(value)
+
+    ensure_result_object(result, origin: :block)
+  end
+
   def ensure_result_object(result, origin:)
     raise Error::UnexpectedOutcome.build(outcome: result, origin: origin) unless result.is_a?(::BCDD::Result)
 

diff --git a/lib/bcdd/result/context.rb b/lib/bcdd/result/context.rb
@@ -40,7 +40,7 @@ def and_then(method_name = nil, **context_data, &block)
       -1
     end
 
-    def call_subject_method(method_name, context)
+    def call_and_then_subject_method(method_name, context)
       method = subject.method(method_name)
 
       acc.merge!(value.merge(context))
@@ -55,6 +55,12 @@ def call_subject_method(method_name, context)
       ensure_result_object(result, origin: :method)
     end
 
+    def call_and_then_block(block)
+      acc.merge!(value)
+
+      call_and_then_block!(block, acc)
+    end
+
     def ensure_result_object(result, origin:)
       raise_unexpected_outcome_error(result, origin) unless result.is_a?(Context)
 

diff --git a/lib/bcdd/result/context/failure.rb b/lib/bcdd/result/context/failure.rb
@@ -3,7 +3,7 @@
 class BCDD::Result::Context::Failure < BCDD::Result::Context
   include BCDD::Result::Failure::Methods
 
-  def and_expose(_type, _keys)
+  def and_expose(_type, _keys, **_options)
     self
   end
 end
diff --git a/lib/bcdd/result/context/success.rb b/lib/bcdd/result/context/success.rb
@@ -3,13 +3,13 @@
 class BCDD::Result::Context::Success < BCDD::Result::Context
   include ::BCDD::Result::Success::Methods
 
-  def and_expose(type, keys)
+  def and_expose(type, keys, halted: true)
     unless keys.is_a?(::Array) && !keys.empty? && keys.all?(::Symbol)
       raise ::ArgumentError, 'keys must be an Array of Symbols'
     end
 
     exposed_value = acc.merge(value).slice(*keys)
 
-    self.class.new(type: type, value: exposed_value, subject: subject)
+    self.class.new(type: type, value: exposed_value, subject: subject, halted: halted)
   end
 end
diff --git a/sig/bcdd/result.rbs b/sig/bcdd/result.rbs
@@ -55,7 +55,9 @@ class BCDD::Result
 
   def kind: -> Symbol
   def known: (Proc) -> untyped
-  def call_subject_method: (Symbol, untyped) -> BCDD::Result
+  def call_and_then_subject_method: (Symbol, untyped) -> BCDD::Result
+  def call_and_then_block: (untyped) -> BCDD::Result
+  def call_and_then_block!: (untyped, untyped) -> BCDD::Result
   def ensure_result_object: (untyped, origin: Symbol) -> BCDD::Result
 end
 
@@ -442,7 +444,7 @@ class BCDD::Result::Context < BCDD::Result
 
   private
 
-  def call_subject_method: (Symbol, Hash[Symbol, untyped]) -> BCDD::Result::Context
+  def call_and_then_subject_method: (Symbol, Hash[Symbol, untyped]) -> BCDD::Result::Context
   def ensure_result_object: (untyped, origin: Symbol) -> BCDD::Result::Context
 
   def raise_unexpected_outcome_error: (BCDD::Result::Context | untyped, Symbol) -> void
@@ -452,7 +454,7 @@ class BCDD::Result::Context
   class Success < BCDD::Result::Context
     include BCDD::Result::Success::Methods
 
-    def and_expose: (Symbol, Array[Symbol]) -> BCDD::Result::Context::Success
+    def and_expose: (Symbol, Array[Symbol], halted: bool) -> BCDD::Result::Context::Success
   end
 
   def self.Success: (Symbol, **untyped) -> BCDD::Result::Context::Success
@@ -462,7 +464,7 @@ class BCDD::Result::Context
   class Failure < BCDD::Result::Context
     include BCDD::Result::Failure::Methods
 
-    def and_expose: (Symbol, Array[Symbol]) -> BCDD::Result::Context::Failure
+    def and_expose: (Symbol, Array[Symbol], **untyped) -> BCDD::Result::Context::Failure
   end
 
   def self.Failure: (Symbol, **untyped) -> BCDD::Result::Context::Failure

diff --git a/test/bcdd/result/context/and_expose/halting_test.rb b/test/bcdd/result/context/and_expose/halting_test.rb
@@ -0,0 +1,85 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class BCDD::Result
+  class ContextHaltingTest < Minitest::Test
+    module HaltingEnabledAndThenBlock
+      extend self, Context.mixin
+
+      def call
+        Success(:a, a: 1)
+          .and_then { Success(:b, b: 2) }
+          .and_expose(:a_and_b, %i[a b])  # the default is halted
+          .and_then { Success(:c, c: 3) }
+      end
+    end
+
+    module HaltingEnabledAndThenMethod
+      extend self, Context.mixin
+
+      def call
+        call_a
+          .and_then(:call_b)
+          .and_expose(:a_and_b, %i[a b])  # the default is halted
+          .and_then(:call_c)
+      end
+
+      private
+
+      def call_a; Success(:a, a: 1); end
+      def call_b; Success(:b, b: 2); end
+      def call_c; Success(:c, c: 3); end
+    end
+
+    module HaltingDisabledAndThenBlock
+      extend self, Context.mixin
+
+      def call
+        Success(:a, a: 1)
+          .and_then { Success(:b, b: 2) }
+          .and_expose(:a_and_b, %i[a b], halted: false)
+          .and_then { Success(:c, c: 3) }
+      end
+    end
+
+    module HaltingDisabledAndThenMethod
+      extend self, Context.mixin
+
+      def call
+        call_a
+          .and_then(:call_b)
+          .and_expose(:a_and_b, %i[a b], halted: false)
+          .and_then(:call_c)
+      end
+
+      private
+
+      def call_a; Success(:a, a: 1); end
+      def call_b; Success(:b, b: 2); end
+      def call_c; Success(:c, c: 3); end
+    end
+
+    test 'by default, #and_expose halts the execution' do
+      result1 = HaltingEnabledAndThenBlock.call
+      result2 = HaltingEnabledAndThenMethod.call
+
+      assert result1.success?(:a_and_b)
+      assert_equal({ a: 1, b: 2 }, result1.value)
+
+      assert result2.success?(:a_and_b)
+      assert_equal({ a: 1, b: 2 }, result2.value)
+    end
+
+    test 'when halted is false, #and_expose does not halt the execution' do
+      result1 = HaltingDisabledAndThenBlock.call
+      result2 = HaltingDisabledAndThenMethod.call
+
+      assert result1.success?(:c)
+      assert_equal({ c: 3 }, result1.value)
+
+      assert result2.success?(:c)
+      assert_equal({ c: 3 }, result2.value)
+    end
+  end
+end