fix: more context when failed to load workspace member

Author: weihanglo

src/cargo/core/workspace.rs

@@ -645,7 +645,13 @@ impl<'cfg> Workspace<'cfg> {
         };
 
         for path in &members_paths {
-            self.find_path_deps(&path.join("Cargo.toml"), &root_manifest_path, false)?;
+            self.find_path_deps(&path.join("Cargo.toml"), &root_manifest_path, false)
+                .with_context(|| {
+                    format!(
+                        "failed to load manifest for workspace member `{}`",
+                        path.display()
+                    )
+                })?;
         }
 
         if let Some(default) = default_members_paths {

tests/testsuite/workspaces.rs

@@ -408,7 +408,10 @@ fn invalid_members() {
         .with_status(101)
         .with_stderr(
             "\
-error: failed to read `[..]Cargo.toml`
+[ERROR] failed to load manifest for workspace member `[..]/foo`
+
+Caused by:
+  failed to read `[..]foo/foo/Cargo.toml`
 
 Caused by:
   [..]
@@ -1869,7 +1872,10 @@ fn glob_syntax_invalid_members() {
         .with_status(101)
         .with_stderr(
             "\
-error: failed to read `[..]Cargo.toml`
+[ERROR] failed to load manifest for workspace member `[..]/crates/bar`
+
+Caused by:
+  failed to read `[..]foo/crates/bar/Cargo.toml`
 
 Caused by:
   [..]