Table of Contents for
Your Code as a Crime Scene

Version ebook / Retour

Cover image for bash Cookbook, 2nd Edition Your Code as a Crime Scene by Adam Tornhill Published by Pragmatic Bookshelf, 2015
  1. Title Page
  2. Your Code as a Crime Scene
  3. Your Code as a Crime Scene
  4. For the Best Reading Experience...
  5. Table of Contents
  6. Early praise for Your Code as a Crime Scene
  7. Foreword by Michael Feathers
  8. Acknowledgments
  9. Chapter 1: Welcome!
  10. About This Book
  11. Optimize for Understanding
  12. How to Read This Book
  13. Toward a New Approach
  14. Get Your Investigative Tools
  15. Part 1: Evolving Software
  16. Chapter 2: Code as a Crime Scene
  17. Meet the Problems of Scale
  18. Get a Crash Course in Offender Profiling
  19. Profiling the Ripper
  20. Apply Geographical Offender Profiling to Code
  21. Learn from the Spatial Movement of Programmers
  22. Find Your Own Hotspots
  23. Chapter 3: Creating an Offender Profile
  24. Mining Evolutionary Data
  25. Automated Mining with Code Maat
  26. Add the Complexity Dimension
  27. Merge Complexity and Effort
  28. Limitations of the Hotspot Criteria
  29. Use Hotspots as a Guide
  30. Dig Deeper
  31. Chapter 4: Analyze Hotspots in Large-Scale Systems
  32. Analyze a Large Codebase
  33. Visualize Hotspots
  34. Explore the Visualization
  35. Study the Distribution of Hotspots
  36. Differentiate Between True Problems and False Positives
  37. Chapter 5: Judge Hotspots with the Power of Names
  38. Know the Cognitive Advantages of Good Names
  39. Investigate a Hotspot by Its Name
  40. Understand the Limitations of Heuristics
  41. Chapter 6: Calculate Complexity Trends from Your Code’s Shape
  42. Complexity by the Visual Shape of Programs
  43. Learn About the Negative Space in Code
  44. Analyze Complexity Trends in Hotspots
  45. Evaluate the Growth Patterns
  46. From Individual Hotspots to Architectures
  47. Part 2: Dissect Your Architecture
  48. Chapter 7: Treat Your Code As a Cooperative Witness
  49. Know How Your Brain Deceives You
  50. Learn the Modus Operandi of a Code Change
  51. Use Temporal Coupling to Reduce Bias
  52. Prepare to Analyze Temporal Coupling
  53. Chapter 8: Detect Architectural Decay
  54. Support Your Redesigns with Data
  55. Analyze Temporal Coupling
  56. Catch Architectural Decay
  57. React to Structural Trends
  58. Scale to System Architectures
  59. Chapter 9: Build a Safety Net for Your Architecture
  60. Know What’s in an Architecture
  61. Analyze the Evolution on a System Level
  62. Differentiate Between the Level of Tests
  63. Create a Safety Net for Your Automated Tests
  64. Know the Costs of Automation Gone Wrong
  65. Chapter 10: Use Beauty as a Guiding Principle
  66. Learn Why Attractiveness Matters
  67. Write Beautiful Code
  68. Avoid Surprises in Your Architecture
  69. Analyze Layered Architectures
  70. Find Surprising Change Patterns
  71. Expand Your Analyses
  72. Part 3: Master the Social Aspects of Code
  73. Chapter 11: Norms, Groups, and False Serial Killers
  74. Learn Why the Right People Don’t Speak Up
  75. Understand Pluralistic Ignorance
  76. Witness Groupthink in Action
  77. Discover Your Team’s Modus Operandi
  78. Mine Organizational Metrics from Code
  79. Chapter 12: Discover Organizational Metrics in Your Codebase
  80. Let’s Work in the Communication Business
  81. Find the Social Problems of Scale
  82. Measure Temporal Coupling over Organizational Boundaries
  83. Evaluate Communication Costs
  84. Take It Step by Step
  85. Chapter 13: Build a Knowledge Map of Your System
  86. Know Your Knowledge Distribution
  87. Grow Your Mental Maps
  88. Investigate Knowledge in the Scala Repository
  89. Visualize Knowledge Loss
  90. Get More Details with Code Churn
  91. Chapter 14: Dive Deeper with Code Churn
  92. Cure the Disease, Not the Symptoms
  93. Discover Your Process Loss from Code
  94. Investigate the Disposal Sites of Killers and Code
  95. Predict Defects
  96. Time to Move On
  97. Chapter 15: Toward the Future
  98. Let Your Questions Guide Your Analysis
  99. Take Other Approaches
  100. Let’s Look into the Future
  101. Write to Evolve
  102. Appendix 1: Refactoring Hotspots
  103. Refactor Guided by Names
  104. Bibliography
  105. You May Be Interested In…

Learn Why the Right People Don’t Speak Up

In the early 1990s, Sweden had its first serial killer. The case led to an unprecedented manhunt. Not for an offender—he was already locked up—but for the victims. There were no bodies.

A year earlier, Thomas Quick, incarcerated in a mental institution, started confessing to one brutal murder after another. The killings Quick confessed to were all well-known unsolved cases.

Over the course of some hectic years, Swedish and Norwegian law enforcement dug around in forests and traveled all across the country in search of hard evidence. At the height of the craze, they even emptied a lake. Yet not a single bone was found.

This striking lack of evidence didn’t prevent the courts from sentencing Quick to eight of the murders. His story was judged as plausible because he knew detailed facts that only the true killer could’ve known. Except Quick was innocent. He fell prey to powerful cognitive and social biases.

The story about Thomas Quick is a case study in the dangers of social biases in groups. The setting is much different from what we encounter in our daily lives, but the biases aren’t. The social forces that led to the Thomas Quick disaster are present in any software project.

See How We Influence Each Other

We’ll get back to the resolution of the Quick story soon. But let’s first understand the social biases so we can prevent our own group disasters.

When we work together in a group to accomplish something—for example, to design that amazing web application that will knock Google Search down—we influence each other. Together, we turn seemingly impossible things into reality. Other times, the group fails miserably. In both cases, the group exhibits what social scientists call process loss.

Process loss is the theory that groups, just as machines, cannot operate at 100 percent efficiency. The act of working together has several costs that we need to keep in check. These costs are losses in coordination and motivation. In fact, most studies on groups find that they perform below their potential.

images/Chp11_ProcessLoss.png

So why do we choose to work in groups when it’s obviously inefficient? Well, often the task itself is too big for a single individual. Today’s software products are so large and complex that we have no other choice than to build an organization around them. We just have to remember that as we move to teams and hierarchies, we pay a price: process loss.

When we pay for something, we expect a return. We know we’ll lose a little efficiency in all team efforts; it’s inevitable. (You’ll learn more about coordination and communication in subsequent chapters.) What’s worse is that social forces may rip your group’s efforts into shreds and leave nothing but broken designs and bug-ridden code behind. Let’s see what we can do to avoid that.

Learn About Social Biases

Pretend for a moment that you’ve joined a new team. On your first day, the team gathers to discuss two design alternatives. You get a short overview before the team leader suggests that you all vote for the best alternative.

It probably sounds a little odd to you. You don’t know enough about the initial problem, and you’d rather see a simple prototype of each suggested design to make an informed decision. So, what do you do?

If you’re like most of us, you start to look around. You look at how your colleagues react. Since they all seem comfortable and accepting of the proposed decision procedure, you choose to go along with the group. After all, you’re fresh on the team, and you don’t want to start by rejecting something everyone else believes in. As in Hans Christian Andersen’s fairy tale, no one mentions that the emperor is naked. Let’s see why. But before we do, we have to address an important question about the role of the overall culture.

Isn’t All This Group Stuff Culture-Dependent?

Sure, different cultures vary in how sensitive they are to certain biases. Most research on the topic has focused on East-West differences. But we don’t need to look that far. To understand how profoundly culture affects us, let’s look at different programming communities.

images/DonaldAPL300.jpg

Take a look at the code in the speech balloon. It’s a piece of APL code. APL is part of the family of array programming languages. The first time you see APL code, it will probably look just like this figure: a cursing cartoon character or plain line noise. But there’s a strong logic to it that results in compact programs. This compactness leads to a different mindset.

The APL code calculates six lottery numbers, guaranteed to be unique, and returns them sorted in ascending order.[30] As you see in the code, there are no intermediate variables to reveal the code’s intent. Contrast this with how a corresponding Java solution would look.

Object-oriented programmers value descriptive names such as randomLotteryNumberGenerator. To an APL programmer, that’s line noise that obscures the real intent of the code. The reason we need more names in Java, C#, or C++ is that our logic—the stuff that really does something—is spread out across multiple functions and classes. When our language allows us to express all of that functionality in a one-liner, our context is different, and it affects the way we and our community think.

Different cultures have different values that affect how their members behave. Just remember that when you choose a technology, you also choose a culture.