refact: remove virtual package

src/path.rs

@@ -0,0 +1,181 @@
+/*!
+All functions related to `pacdef`'s internal paths.
+*/
+
+use std::path::PathBuf;
+use std::{env, path::Path};
+
+use anyhow::{Context, Result};
+use path_absolutize::Absolutize;
+
+const CONFIG_FILE_NAME: &str = "pacdef.toml";
+const CONFIG_FILE_NAME_OLD: &str = "pacdef.yaml";
+
+/// Get the group directory where all group files are located. This is
+/// `$XDG_CONFIG_HOME/pacdef/groups`, which defaults to `$HOME/.config/pacdef/groups`.
+///
+/// # Errors
+///
+/// This function returns an error if both `$XDG_CONFIG_HOME` and `$HOME` are undefined.
+pub fn get_group_dir() -> Result<PathBuf> {
+    let mut result = get_pacdef_base_dir().context("getting pacdef base dir")?;
+    result.push("groups");
+    Ok(result)
+}
+
+/// Get the base directory for `pacdef`'s config files.
+///
+/// # Errors
+///
+/// This function will return an error if `$XDG_CONFIG_HOME` cannot be determined.
+pub fn get_pacdef_base_dir() -> Result<PathBuf> {
+    let mut dir = get_xdg_config_home().context("getting XDG_CONFIG_HOME")?;
+    dir.push("pacdef");
+    Ok(dir)
+}
+
+/// Get the path to the cargo home directory.
+///
+/// # Errors
+///
+/// This function will return an error if neither the `$CARGO_HOME` nor
+/// the `$HOME` environment variables are set.
+pub fn get_cargo_home() -> Result<PathBuf> {
+    if let Ok(config) = env::var("CARGO_HOME") {
+        Ok(config.into())
+    } else {
+        let mut config = get_home_dir().context("falling back to $HOME/.cargo")?;
+        config.push(".cargo");
+        Ok(config)
+    }
+}
+
+/// Get the path to the XDG config directory.
+///
+/// # Errors
+///
+/// This function will return an error if neither the `$XDG_CONFIG_HOME` nor
+/// the `$HOME` environment variables are set.
+fn get_xdg_config_home() -> Result<PathBuf> {
+    if let Ok(config) = env::var("XDG_CONFIG_HOME") {
+        Ok(config.into())
+    } else {
+        let mut config = get_home_dir().context("falling back to $HOME/.config")?;
+        config.push(".config");
+        Ok(config)
+    }
+}
+
+/// Get the home directory of the current user from the `$HOME` environment
+/// variable.
+///
+/// # Errors
+///
+/// This function will return an error if the `$HOME` variable is not set.
+pub fn get_home_dir() -> Result<PathBuf> {
+    Ok(env::var("HOME").context("getting $HOME variable")?.into())
+}
+
+/// Get the path to the pacdef config file. This is `$XDG_CONFIG_HOME/pacdef/pacdef.toml`.
+///
+/// # Errors
+///
+/// This function returns an error if both `$XDG_CONFIG_HOME` and `$HOME` are
+/// undefined.
+pub fn get_config_path() -> Result<PathBuf> {
+    let mut file = get_pacdef_base_dir().context("getting pacdef base dir for config file")?;
+    file.push(CONFIG_FILE_NAME);
+    Ok(file)
+}
+
+/// Get the path to the pacdef config file from version 0.x. This is
+/// `$XDG_CONFIG_HOME/pacdef/pacdef.conf`.
+///
+/// # Errors
+///
+/// This function returns an error if both `$XDG_CONFIG_HOME` and `$HOME` are
+/// undefined.
+pub fn get_config_path_old_version() -> Result<PathBuf> {
+    let mut file = get_pacdef_base_dir().context("getting pacdef base dir for config file")?;
+    file.push(CONFIG_FILE_NAME_OLD);
+    Ok(file)
+}
+
+/// Determine if a program `name` exists in the folders in the `$PATH` variable.
+///
+/// # Errors
+///
+/// This function returns an error if `$PATH` is not set.
+pub fn binary_in_path(name: &str) -> Result<bool> {
+    let paths = env::var_os("PATH").context("getting $PATH")?;
+    for dir in env::split_paths(&paths) {
+        let full_path = dir.join(name);
+        if full_path.is_file() {
+            return Ok(true);
+        }
+    }
+    Ok(false)
+}
+
+/// Determine the relative path of `full_path` in relation to `base_path`.
+///
+/// # Panics
+///
+/// Panics if at least one element in `base_path` does not match the corresponding
+/// element in `full_path`.
+pub fn get_relative_path<P>(full_path: P, base_path: P) -> PathBuf
+where
+    P: AsRef<Path>,
+{
+    let mut file_iter = full_path.as_ref().iter();
+    base_path
+        .as_ref()
+        .iter()
+        .zip(&mut file_iter)
+        .for_each(|(a, b)| assert_eq!(a, b));
+    let relative_path: PathBuf = file_iter.collect();
+    relative_path
+}
+
+/// For each file argument, return the absolute path to the file.
+///
+/// # Errors
+///
+/// Returns an error if any of the files cannot be absolutized.
+pub fn get_absolutized_file_paths(arg_match: &[String]) -> Result<Vec<PathBuf>> {
+    let mut result = vec![];
+
+    for item in arg_match {
+        let path: PathBuf = item.into();
+        let absolute = path
+            .absolutize()
+            .with_context(|| format!("absolutizing {path:?}"))?
+            .into_owned();
+        result.push(absolute);
+    }
+
+    Ok(result)
+}
+
+#[cfg(test)]
+mod tests {
+    use std::path::PathBuf;
+
+    use super::get_relative_path;
+
+    #[test]
+    fn relative_path() {
+        let full = PathBuf::from("/a/b/c/d/e");
+        let base = PathBuf::from("/a/b/c");
+        let relative = get_relative_path(full, base);
+        assert_eq!(relative, PathBuf::from("d/e"));
+    }
+
+    #[test]
+    #[should_panic]
+    fn relative_path_panic() {
+        let full = PathBuf::from("/a/b/z/d/e");
+        let base = PathBuf::from("/a/b/c");
+        get_relative_path(full, base);
+    }
+}