Move CLI building to cli.rs

src/cli.rs

@@ -1,12 +1,16 @@
 use std::env;
 use std::path::PathBuf;
 use structopt::StructOpt;
+use structopt::clap::ErrorKind as ClapError;
 
 // To get effective user id (EUID) so that setuid works
 use users::{get_effective_uid,get_user_by_uid};
 // For home directory
 use users::os::unix::UserExt;
 
+use crate::log;
+use crate::log::Context;
+
 #[derive(Debug, StructOpt)]
 #[structopt(
     name = "forgebuild",
@@ -24,6 +28,42 @@ pub struct Cli {
 }
 
 impl Cli {
+    /// Builds the command-line from passed arguments
+    /// Returns the Cli instance alongside a PathBuf of the basedir
+    pub fn build() -> (Self, PathBuf) {
+        // We create a dedicated context so we don't have to pass it as argument
+        let mut context = Context::new();
+
+        // We don't want to use structopt's error handler for unknown argument as we have our own
+        // error message for that case (unknown_arg). So we use from_iter_safe() not from_args()
+        match Cli::from_iter_safe(std::env::args()) {
+            Ok(cmd) => {
+                // Parsing was successful, but we'd like to ensure requested basedir exists
+                match cmd.basedir().canonicalize() {
+                    Ok(p) => {
+                        (cmd, p)
+                    },
+                    Err(_) => {
+                        // Missing basedir
+                        context.insert("$i18n_basedir".to_string(), cmd.basedir().to_str().unwrap().to_string());
+                        log::error("missing_basedir", &context);
+                        std::process::exit(1);
+                    }
+                }
+            },
+            Err(e) => {
+                match &e.kind {
+                    ClapError::UnknownArgument => {
+                        context.insert("$i18n_arg".to_string(), e.info.unwrap().first().unwrap().to_string());
+                        log::error("unknown_arg", &context);
+                        std::process::exit(1);
+                    },
+                    _ => e.exit()
+                }
+            }
+        }
+    }
+
     /// Returns a PathBuf to the basedir. If it's a relative link,
     /// it's not expanded here! Panics if no basedir is provided and $HOME isn't defined
     pub fn basedir(&self) -> PathBuf {

src/main.rs

@@ -1,7 +1,4 @@
 use std::env::{set_current_dir as cd, set_var};
-use structopt::StructOpt;
-use structopt::clap::ErrorKind as ClapError;
-// For UNIX extended metadata
 
 mod cli;
 mod db;
@@ -13,41 +10,8 @@ use log::Context;
 
 fn main() -> Result<(), std::io::Error> {
     let mut context = Context::new();
-
-    // TODO: use StructOpt::from_iter_safe so we can hook on Cli error
-    // to display additional unknown_arg error message.
-    //let cmd = cli::Cli::from_args();
-    let res = cli::Cli::from_iter_safe(std::env::args());
-    if res.is_err() {
-        let e = res.unwrap_err();
-        match &e.kind {
-            ClapError::UnknownArgument => {
-                context.insert("$i18n_arg".to_string(), e.info.unwrap().first().unwrap().to_string());
-                log::error("unknown_arg", &context);
-                std::process::exit(1);
-            },
-            /*ClapError::HelpDisplayed {
-                e.exit()
-            }*/
-            _ => e.exit()
-        }
-    }
-    let cmd = res.unwrap();
-
-    let basedir = cmd.basedir();
+    let (cmd, basedir) = cli::Cli::build();
     context.insert("$i18n_basedir".to_string(), basedir.to_str().unwrap().to_string());
-
-    let basedir = match basedir.canonicalize() {
-        Ok(p) => {
-            context.insert("$i18n_basedir".to_string(), p.to_str().unwrap().to_string());
-            p
-        },
-        Err(_) => {
-            log::error("missing_basedir", &context);
-            std::process::exit(1);
-        }
-    };
-
     let basedir_str = basedir.to_str().unwrap().to_string();
 
     set_var("GITBUILDDIR", &basedir);