Merge pull request #220 from deg4uss3r/cargo_home_fix

Removed the always matching blank string for the CARGO_HOME variable which fixes an error users were seeing when running `cargo-outdated` and not setting the `CARGO_HOME` environment variable (`rustup` shims always set it for you).
diff --git a/Cargo.lock b/Cargo.lock
index ad744f9..cc806e0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -140,7 +140,7 @@
 
 [[package]]
 name = "cargo-outdated"
-version = "0.9.9"
+version = "0.9.10"
 dependencies = [
  "anyhow",
  "cargo",
diff --git a/Cargo.toml b/Cargo.toml
index 85893f8..2a2d0dc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cargo-outdated"
-version = "0.9.9"
+version = "0.9.10"
 authors = [
     "Kevin K. <kbknapp@gmail.com>",
     "Frederick Z. <frederick888@tsundere.moe>",
diff --git a/src/cargo_ops/temp_project.rs b/src/cargo_ops/temp_project.rs
index 24ccf06..e147789 100644
--- a/src/cargo_ops/temp_project.rs
+++ b/src/cargo_ops/temp_project.rs
@@ -654,13 +654,17 @@
         visited.insert(pkg_id);
         let pkg = &elab.pkgs[&pkg_id];
         let pkg_path = pkg.root().to_string_lossy();
+
+        // Checking if there's a CARGO_HOME set and that it is not an empty string
         let cargo_home_path = match std::env::var_os("CARGO_HOME") {
-             Some(path) => path.into_string().expect("Error getting string from OsString"),
-             None => "".to_string(),
+             Some(path) if !path.is_empty() => Some(path.into_string().expect("Error getting string from OsString")),
+             _ => None,
          };
 
+         // If there is a CARGO_HOME make sure we do not crawl the registry for more Cargo.toml files
+         // Otherwise add all Cargo.toml files to the manifest paths 
          if pkg_path.starts_with(workspace_path) {
-             if !pkg_path.starts_with(&cargo_home_path){
+             if cargo_home_path.is_none() || !pkg_path.starts_with(&cargo_home_path.expect("Error extracting CARGO_HOME string")) {
                  manifest_paths.push(pkg.manifest_path().to_owned());
              }
          }