google/closure-compiler

String.fromCharCode optimization

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#3,606 创建于 2020年5月27日

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 (10 评论) (0 反应) (0 负责人)Java (7,176 star) (1,197 fork)batch import
P4featgood first issue

描述

I used: https://closure-compiler.appspot.com/home

Input code: document.write(String.fromCharCode(115));

Expected output: document.write("s")

Actual output: document.write(String.fromCharCode(115));

I expected the String.fromCharCode function to be removed to just the resulting character.

贡献者指南

技术栈
javascript
领域
performance
议题类型
feature
难度面向新贡献者的预计实现难度，1 表示很小改动，5 表示专家级工作。
3
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1-2 days
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stale
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clear
前置要求
JavaJavaScriptAST manipulationoptimization passes
新手友好度1-100 的估计分数，表示该议题对首次贡献者的友好程度。
40
研究方向
Investigate the existing peephole optimization passes in the Closure Compiler, particularly the 'PeepholeOptimizations' class that handles constant folding. Look for patterns where function calls with constant arguments are replaced with the result. For String.fromCharCode with a single numeric argument, the optimization should replace it with the corresponding character string. Check the existing tests in the 'test' directory for similar optimizations to understand the required test structure. Consider examining the 'ProcessClosurePrimitives' or 'ReplaceStrings' passes for relevant logic.