build-fs-tree：快速创建目录结构和文件的Rust工具库

build-fs-tree 是一个用于快速构建文件系统目录结构的Rust库，它允许开发者通过简单的Rust数据结构描述目录树，并自动创建相应的文件和目录。

功能特点

• 通过Rust数据结构声明式创建目录结构
• 支持创建文件和目录
• 支持文件内容写入
• 跨平台兼容（Windows/Unix）
• 轻量级且无额外依赖

基本使用方法

添加依赖

首先在Cargo.toml中添加依赖：

[dependencies]
build-fs-tree = "0.4"

基本示例

use build_fs_tree::{dir, file, FileSystemTree};
use std::fs;

fn main() -> std::io::Result<()> {
    // 定义目录结构
    let tree = dir! {
        "project_root" => dir! {
            "src" => dir! {
                "main.rs" => file!("fn main() {\n    println!(\"Hello, world!\");\n}")
            },
            "Cargo.toml" => file!(r#"
                [package]
                name = "my-project"
                version = "0.1.0"
                edition = "2021"
            "#)
        }
    };

    // 创建实际文件和目录
    tree.build(".")?;

    Ok(())
}

高级用法

从现有结构创建

use build_fs_tree::FileSystemTreeBuilder;

let mut builder = FileSystemTreeBuilder::new();
builder
    .add_dir("parent_dir")?
    .add_dir("parent_dir/child_dir")?
    .add_file("parent_dir/file.txt", "File contents")?;

let tree = builder.build();
tree.build("target_directory")?;

使用Buildable trait

use build_fs_tree::{dir, file, Buildable};

let tree = dir! {
    "config" => dir! {
        "settings.json" => file!(r#"{"debug": true}"#)
    }
};

// 构建到特定路径
tree.build("my_app")?;

处理已存在文件

默认情况下，如果目标文件已存在，build-fs-tree会返回错误。可以通过force方法覆盖：

tree.force().build("path")?;

实际应用示例

创建项目脚手架

use build_fs_tree::{dir, file};

fn create_project_scaffold(project_name: &str) -> std::io::Result<()> {
    let tree = dir! {
        project_name => dir! {
            "src" => dir! {
                "main.rs" => file!("fn main() {\n    println!(\"Hello from {}!\");\n}", project_name),
                "lib.rs" => file!("pub fn greet() {\n    println!(\"Hello!\");\n}")
            },
            "tests" => dir! {
                "integration_test.rs" => file!(r#"
                    use my_project::greet;

                    #[test]
                    fn test_greet() {
                        greet();
                    }
                "#)
            },
            ".gitignore" => file!("/target\nCargo.lock"),
            "Cargo.toml" => file!(format!(r#"
                [package]
                name = "{}"
                version = "0.1.0"
                edition = "2021"

                [dependencies]
            "#, project_name))
        }
    };

    tree.build(".")?;
    Ok(())
}

创建配置文件结构

use build_fs_tree::{dir, file};

fn create_config_structure() -> std::io::Result<()> {
    let tree = dir! {
        "config" => dir! {
            "database" => dir! {
                "postgresql.conf" => file!(r#"
                    host = "localhost"
                    port = 5432
                    username = "admin"
                "#),
                "redis.conf" => file!(r#"
                    host = "127.0.0.1"
                    port = 6379
                "#)
            },
            "application" => dir! {
                "server.toml" => file!(r#"
                    [server]
                    port = 8080
                    workers = 4
                "#),
                "logging.yaml" => file!(r#"
                    level: info
                    format: json
                "#)
            }
        }
    };

    tree.build(".")?;
    Ok(())
}

完整示例demo

下面是一个结合了多种功能的完整示例：

use build_fs_tree::{dir, file, FileSystemTreeBuilder, Buildable};
use std::path::Path;

fn setup_test_environment() -> std::io::Result<()> {
    // 使用dir!宏创建基本结构
    let mut tree = dir! {
        "test_project" => dir! {
            "src" => dir! {
                "utils.rs" => file!(r#"
                    pub fn add(a: i32, b: i32) -> i32 {
                        a + b
                    }
                "#),
                "tests" => dir! {
                    "test_utils.rs" => file!(r#"
                        use super::*;

                        #[test]
                        fn test_add() {
                            assert_eq!(add(2, 3), 5);
                        }
                    "#)
                }
            },
            "config" => dir! {
                "app.toml" => file!(r#"
                    [settings]
                    debug = true
                    port = 8080
                "#)
            }
        }
    };

    // 使用FileSystemTreeBuilder添加更多内容
    let mut builder = FileSystemTreeBuilder::new();
    builder
        .add_dir("test_project/assets")?
        .add_file("test_project/assets/logo.png", "")? // 空文件，实际使用时可填充真实数据
        .add_file("test_project/README.md", "# Test Project\n\nThis is a sample project.")?;

    let additional_tree = builder.build();
    
    // 合并两个目录结构
    tree.merge(additional_tree);
    
    // 强制构建（覆盖已存在文件）
    tree.force().build(Path::new("test_dir"))?;
    
    Ok(())
}

fn main() -> std::io::Result<()> {
    // 创建测试环境
    setup_test_environment()?;
    
    // 创建项目脚手架
    create_project_scaffold("my_app")?;
    
    // 创建配置文件结构
    create_config_structure()?;
    
    Ok(())
}

注意事项

1. 路径分隔符会自动根据操作系统转换
2. 默认情况下不会覆盖已存在的文件（除非使用force()）
3. 创建的文件权限遵循操作系统默认设置
4. 对于大型目录结构，考虑使用FileSystemTreeBuilder逐步构建

build-fs-tree特别适合测试场景（需要临时目录结构）、项目生成器和需要快速创建复杂目录结构的应用场景。