Design Patterns #400
Design Patterns #400
Conversation
WalkthroughFive design pattern documentation files in chapter 9 received comprehensive updates: Observer, Strategy, and Factory Method now include full Go implementations with explanatory sections; Adapter was reformatted with shortcode wrapping; Decorator gained structured documentation with a complete practical example. Changes
Estimated code review effort🎯 3 (Moderate) | ⏱️ ~20 minutes
Suggested reviewers
Poem
Pre-merge checks and finishing touches❌ Failed checks (1 warning, 1 inconclusive)
✅ Passed checks (1 passed)
✨ Finishing touches🧪 Generate unit tests (beta)
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Actionable comments posted: 0
🧹 Nitpick comments (6)
content/chapter 9/structural patterns/9.2.1-adaptor.md (1)
16-79: Fix trailing spaces in code block (static analysis flagged multiple MD009 violations).The static analysis tool flagged hard tabs and trailing spaces throughout the code block (lines 20, 26, 33, 37, 41-43, 50, 54, 58-60, 65-68, 70-77). These are low-priority formatting nits but should be cleaned up to pass linting. Most issues stem from inconsistent indentation in the code block.
content/chapter 9/behavioral patterns/9.3.6-observer.md (1)
104-104: Fix trailing spaces and add final newline.Line 104 has trailing spaces before the closing
{{< /play >}}. Additionally, the file should end with a single newline character per MD047.content/chapter 9/behavioral patterns/9.3.8-strategy.md (1)
104-104: Fix trailing spaces and add final newline.Line 104 has trailing spaces within the code block. Additionally, the file should end with a single newline character per MD047.
Also applies to: 151-151
content/chapter 9/structural patterns/9.2.4-decorator.md (1)
103-103: Fix trailing spaces and add final newline.Line 103 has trailing spaces within the code block. Additionally, the file should end with a single newline character per MD047. (Note: LanguageTool flags at lines 37, 53, 70, 87, 100 are false positives from Persian grammar checking and can be safely ignored.)
Also applies to: 139-139
content/chapter 9/creational patterns/9.1.2-factory-method.md (2)
88-97: Minor note: Error handling in examples uses blank identifier.Lines 90, 93, 96, 101, 104, 109 use
_, _ :=to ignore factory errors. This is pragmatic for teaching examples but worth noting that in production code, errors should be checked. The error handling demonstration in lines 109-114 does show proper error checking, so the pattern is present in the example overall.
88-88: Fix trailing spaces and add final newline.Line 88 has trailing spaces within the code block. Additionally, the file should end with a single newline character per MD047.
Also applies to: 125-125
📜 Review details
Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro
📒 Files selected for processing (5)
content/chapter 9/behavioral patterns/9.3.6-observer.md(1 hunks)content/chapter 9/behavioral patterns/9.3.8-strategy.md(1 hunks)content/chapter 9/creational patterns/9.1.2-factory-method.md(1 hunks)content/chapter 9/structural patterns/9.2.1-adaptor.md(1 hunks)content/chapter 9/structural patterns/9.2.4-decorator.md(1 hunks)
🧰 Additional context used
🪛 LanguageTool
content/chapter 9/structural patterns/9.2.4-decorator.md
[duplication] ~37-~37: اشتباه تایپی متحمل: شما یک کلمه را تکرار کردهاید
Context: ... Base type CoffeeDecorator struct { coffee Coffee } func (c *CoffeeDecorator) Cost() flo...
(PERSIAN_WORD_REPEAT_RULE)
[duplication] ~53-~53: اشتباه تایپی متحمل: شما یک کلمه را تکرار کردهاید
Context: ...offeeDecorator } func NewMilkDecorator(coffee Coffee) *MilkDecorator { return &MilkDecor...
(PERSIAN_WORD_REPEAT_RULE)
[duplication] ~70-~70: اشتباه تایپی متحمل: شما یک کلمه را تکرار کردهاید
Context: ...ffeeDecorator } func NewSugarDecorator(coffee Coffee) *SugarDecorator { return &SugarDec...
(PERSIAN_WORD_REPEAT_RULE)
[duplication] ~87-~87: اشتباه تایپی متحمل: شما یک کلمه را تکرار کردهاید
Context: ...eeDecorator } func NewCaramelDecorator(coffee Coffee) *CaramelDecorator { return &Carame...
(PERSIAN_WORD_REPEAT_RULE)
[duplication] ~100-~100: اشتباه تایپی متحمل: شما یک کلمه را تکرار کردهاید
Context: ... func main() { // Start with basic coffee coffee := &BasicCoffee{} fmt.Printf("%s: $...
(PERSIAN_WORD_REPEAT_RULE)
🪛 markdownlint-cli2 (0.18.1)
content/chapter 9/behavioral patterns/9.3.6-observer.md
104-104: Trailing spaces
Expected: 0 or 2; Actual: 4
(MD009, no-trailing-spaces)
content/chapter 9/structural patterns/9.2.4-decorator.md
103-103: Trailing spaces
Expected: 0 or 2; Actual: 4
(MD009, no-trailing-spaces)
139-139: Files should end with a single newline character
(MD047, single-trailing-newline)
content/chapter 9/behavioral patterns/9.3.8-strategy.md
104-104: Trailing spaces
Expected: 0 or 2; Actual: 4
(MD009, no-trailing-spaces)
153-153: Files should end with a single newline character
(MD047, single-trailing-newline)
content/chapter 9/creational patterns/9.1.2-factory-method.md
88-88: Trailing spaces
Expected: 0 or 2; Actual: 4
(MD009, no-trailing-spaces)
125-125: Files should end with a single newline character
(MD047, single-trailing-newline)
content/chapter 9/structural patterns/9.2.1-adaptor.md
20-20: Hard tabs
Column: 1
(MD010, no-hard-tabs)
26-26: Hard tabs
Column: 1
(MD010, no-hard-tabs)
33-33: Hard tabs
Column: 1
(MD010, no-hard-tabs)
37-37: Hard tabs
Column: 1
(MD010, no-hard-tabs)
41-41: Hard tabs
Column: 1
(MD010, no-hard-tabs)
42-42: Hard tabs
Column: 1
(MD010, no-hard-tabs)
43-43: Hard tabs
Column: 1
(MD010, no-hard-tabs)
50-50: Hard tabs
Column: 1
(MD010, no-hard-tabs)
54-54: Hard tabs
Column: 1
(MD010, no-hard-tabs)
58-58: Hard tabs
Column: 1
(MD010, no-hard-tabs)
59-59: Hard tabs
Column: 1
(MD010, no-hard-tabs)
60-60: Hard tabs
Column: 1
(MD010, no-hard-tabs)
65-65: Hard tabs
Column: 1
(MD010, no-hard-tabs)
66-66: Hard tabs
Column: 1
(MD010, no-hard-tabs)
67-67: Hard tabs
Column: 1
(MD010, no-hard-tabs)
68-68: Hard tabs
Column: 1
(MD010, no-hard-tabs)
70-70: Hard tabs
Column: 1
(MD010, no-hard-tabs)
71-71: Hard tabs
Column: 1
(MD010, no-hard-tabs)
72-72: Hard tabs
Column: 1
(MD010, no-hard-tabs)
73-73: Hard tabs
Column: 1
(MD010, no-hard-tabs)
75-75: Hard tabs
Column: 1
(MD010, no-hard-tabs)
76-76: Hard tabs
Column: 1
(MD010, no-hard-tabs)
77-77: Hard tabs
Column: 1
(MD010, no-hard-tabs)
🔇 Additional comments (9)
content/chapter 9/structural patterns/9.2.1-adaptor.md (1)
16-79: Approve: Adapter pattern correctly implemented with shortcode wrapping.The refactoring to use the
{{< play >}}shortcode wrapper is a good change for executability. The adapter pattern implementation is sound: interfaces are well-defined, and the two concrete adapters (HpAdapter and CanonAdapter) properly delegate to their respective printer implementations while conforming to the IPrint interface.content/chapter 9/behavioral patterns/9.3.6-observer.md (2)
13-104: Approve: Observer pattern correctly implemented with clear separation of concerns.The implementation follows the Observer pattern well: the Subject interface defines the contract for the WeatherStation, the Observer interface is minimal and focused (Update method), and the concrete observers (PhoneDisplay, TVDisplay) react independently. The NotifyObservers call within SetTemperature correctly demonstrates the automatic notification trigger on state change. The code is well-structured and the main function clearly shows observer registration, notification, and removal scenarios.
7-10: Excellent pattern explanation in Persian.The introductory explanation (lines 7-10) provides clear context for the Observer pattern, covering one-to-many relationships, event-driven systems, and decoupling. This sets up the practical example well.
content/chapter 9/behavioral patterns/9.3.8-strategy.md (2)
13-151: Approve: Strategy pattern excellently implemented with both context and functional approaches.The code demonstrates the Strategy pattern comprehensively. Four concrete payment strategies are well-encapsulated, each with appropriate constructors and Pay methods. The PaymentProcessor context shows the classic approach, while the standalone ProcessPayment function (lines 96-99) demonstrates Go's idiomatic, more lightweight alternative. The main function is particularly strong: it showcases context usage (lines 102-120), the functional approach (lines 122-127), dynamic runtime strategy switching (lines 129-145), and error handling (lines 147-149). The nil check on line 90 prevents crashes when no strategy is set.
7-10: Excellent pattern explanation in Persian.The explanation (lines 7-10) clearly articulates the Strategy pattern's benefits: algorithm family encapsulation, runtime switching, client independence, and Open/Closed principle adherence. This context is valuable for readers.
content/chapter 9/structural patterns/9.2.4-decorator.md (2)
13-137: Approve: Decorator pattern correctly implemented using Go embedding and composition.The implementation is well-done: the Coffee interface is clean, BasicCoffee provides a sensible base (line 25-33), and CoffeeDecorator uses embedding to delegate to the wrapped coffee object. Each concrete decorator (MilkDecorator, SugarDecorator, CaramelDecorator) properly overrides Cost and Description while maintaining the interface contract. The main function clearly demonstrates dynamic composition: building a complex coffee from basic coffee through successive decorator wrapping (lines 128-134 shows a 3-level nesting). This is an excellent example of the pattern in Go.
7-11: Excellent pattern explanation with clear subsections.The explanation (lines 7-11) well articulates the Decorator pattern's purpose: adding responsibilities dynamically without structural changes, using composition over inheritance, and avoiding class hierarchy explosion. The subsection structure (9.2.4.1 explanation, 9.2.4.2 example) is clear and pedagogically sound.
content/chapter 9/creational patterns/9.1.2-factory-method.md (2)
13-123: Approve: Factory Method pattern correctly implemented with struct and functional approaches.The implementation is solid: the Vehicle interface defines the contract, and three concrete products (Car, Motorcycle, Truck) implement it cleanly. The VehicleFactory struct demonstrates the classic factory approach, while the standalone CreateVehicle function (lines 72-83) shows Go's idiomatic preference for simple functions over struct methods. Both use switch statements with proper error handling for unknown types. The main function is comprehensive: it demonstrates the struct factory (lines 87-97), the function factory (lines 100-105), error handling (lines 108-114), and polymorphism with a slice of Vehicles (lines 117-121). This is an excellent teaching example.
7-11: Excellent pattern explanation with clear subsections.The explanation (lines 7-11) well describes the Factory Method pattern's purpose: decoupling object creation from clients, handling varying concrete types, and adhering to Open/Closed principle. The two subsections (explanation and practical example) provide good structure.
2 participants
9.2.1 => Modify example format and make it executable
9.3.6 => Add Observer design pattern
9.2.4 => Add Decorator design pattern
9.1.2 => Add Factory Method design pattern
9.3.8 => Add Strategy design pattern
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