Automated OC Code Refactoring Practice (Part 3): Data Item Read/Write Class Encapsulation and Call Site Adaptation

This article is the third part of a series on using Python scripts to automate Objective-C code refactoring. It explains how to upgrade direct data item read/write operations to indirect access through a data channel.

Data Item Read/Write Class Encapsulation: To reduce refactoring costs, a wrapper class is created in the data item usage module. Each data item's read/write operation is implemented as a static function. The encapsulation rules are: 1) For read operations, the function return type, function name, and data item must match (e.g., NSString *value1 becomes +(NSString *)value1); 2) For update operations, the function follows the pattern set_ + function name (e.g., +(void)set_value1:(NSString *)value). The generated files use XXXSettingReader and XXXSettingWriter as class name prefixes.

Data Item Usage Module Call Site Adaptation: When the data provider module supports data channel access, the data item usage module needs adaptation. This includes two parts: 1) Data item update call site adaptation - converting patterns like [XXXSetting share].value1 = @"str" to [XXXSettingWriter set_value1:@"str"]; 2) Data item read call site adaptation - converting [XXXSetting share].value1 to [XXXSettingReader value1]. The implementation uses Python with regex-based string matching and replacement, supporting whole-word matching to handle cases where data items might be substrings of each other.

The automation approach achieved zero bugs in testing and deployment phases for this refactoring work involving over 600 call sites.