Rewrite configuration parsing to remove special sysroot_path treatment

Author: phil-opp

src/config.rs

@@ -1,28 +1,31 @@
 use serde_json;
 use cargo_metadata;
+use std::path::PathBuf;
 
-#[derive(Debug, Deserialize, Hash)]
+#[derive(Debug, Hash)]
 pub struct Config {
     pub memcpy: bool,
-    pub sysroot_path: Option<String>,
+    pub sysroot_path: PathBuf,
 }
 
-impl Default for Config {
-    fn default() -> Self {
-        Config {
-            memcpy: true,
-            sysroot_path: None,
-        }
-    }
+#[derive(Debug, Deserialize, Default)]
+struct ParseConfig {
+    pub memcpy: Option<bool>,
+    pub sysroot_path: Option<String>,
 }
 
 impl Config {
     pub fn from_metadata(metadata: &cargo_metadata::Metadata) -> Result<Config, serde_json::Error> {
         let package_metadata = metadata.packages.first().map(|p| &p.metadata);
         let crate_metadata = package_metadata.as_ref().and_then(|m| m.get("cargo-xbuild"));
-        match crate_metadata {
-            Some(json) => serde_json::from_value(json.clone()),
-            None => Ok(Config::default())
-        }
+        let config = match crate_metadata {
+            Some(json) => serde_json::from_value(json.clone())?,
+            None => ParseConfig::default(),
+        };
+
+        Ok(Config {
+            memcpy: config.memcpy.unwrap_or(true),
+            sysroot_path: PathBuf::from(config.sysroot_path.unwrap_or("target/sysroot".into())),
+        })
     }
 }

src/main.rs

@@ -147,7 +147,6 @@ fn build(args: cli::Args) -> Result<(ExitStatus)> {
     let metadata =
         cargo_metadata::metadata(args.manifest_path()).expect("cargo metadata invocation failed");
     let root = Path::new(&metadata.workspace_root);
-    let target_directory = Path::new(&metadata.target_directory);
     let crate_config = config::Config::from_metadata(&metadata)
         .map_err(|_| "parsing package.metadata.cargo-xbuild section failed")?;
 
@@ -193,7 +192,7 @@ fn build(args: cli::Args) -> Result<(ExitStatus)> {
     };
 
     if let Some(cmode) = cmode {
-        let home = xargo::home(target_directory, &crate_config)?;
+        let home = xargo::home(root, &crate_config)?;
         let rustflags = cargo::rustflags(config.as_ref(), cmode.triple())?;
 
         sysroot::update(

src/xargo.rs

@@ -1,6 +1,6 @@
 use std::path::{Display, PathBuf};
 use std::process::{Command, ExitStatus};
-use std::{fs, mem};
+use std::mem;
 use std::io::{self, Write};
 use std::path::Path;
 
@@ -69,16 +69,9 @@ impl Home {
     }
 }
 
-pub fn home(target_directory: &Path, config: &Config) -> Result<Home> {
-    let path = if let Some(ref p) = config.sysroot_path {
-        let path = Path::new(p);
-        fs::create_dir_all(&path).map_err(|_| String::from("Could not create sysroot folder"))?;
-        path.canonicalize().map_err(|_| String::from("Invalid sysroot path"))?
-    } else {
-        let mut p = PathBuf::from(target_directory);
-        p.push("sysroot");
-        p
-    };
+pub fn home(root: &Path, config: &Config) -> Result<Home> {
+    let mut path = PathBuf::from(root);
+    path.push(&config.sysroot_path);
 
     Ok(Home {
         path: Filesystem::new(path),