From 027bd44578b207f88229fdf404d5b7f894b55978 Mon Sep 17 00:00:00 2001
From: Bastien Orivel <eijebong@bananium.fr>
Date: Wed, 14 Sep 2022 12:03:47 +0200
Subject: [PATCH] Fix dependency renaming in published crates

Turns out that when a crate uses a dependency with a `package` key, the
meaning of `name` and `rename` gets inverted. This is a bit confusing so
let's look at an example.

We have a package that depends on hyper through a `package` but that has
a local name that doesn't exist in the registry.

```
[package]
name = "test_dep_resolver"
...

[dependencies]
thisdoesntexist = { package = "hyper", version = "0.14" }
```

When published to crates.io, it will generate the following:
(visible here:
https://github.com/rust-lang/crates.io-index/blob/master/te/st/test_dep_resolver)

```
{
  "name": "test_dep_resolver",
  "vers": "0.1.1",
  "deps": [
    {
      "name": "thisdoesntexist",
      "req": "^0.14",
      "features": [],
      "optional": false,
      "default_features": true,
      "target": null,
      "kind": "normal",
      "package": "hyper"
    }
  ],
  "cksum": "1484b56f82049380557a5799807afd981e7d443d053710ff49494db34f151b5a",
  "features": {},
  "yanked": false,
  "links": null
}
```

As we can see, the hyper dependency has the name `thisdoesntexist` and
`package` hyper.

Now let's have a look at the `cargo metadata` output:

```
> cat local | jq '.packages[] | select(.name == "test_dep_resolver") | .dependencies[] | select (.name == "hyper")'
{
  "name": "hyper",
  "source": "registry+https://github.com/rust-lang/crates.io-index",
  "req": "^0.14",
  "kind": null,
  "rename": "thisdoesntexist",
  "optional": false,
  "uses_default_features": true,
  "features": [],
  "target": null,
  "registry": null
}
```

Here we can see `name` is `hyper` and `rename` is `thisdoesntexist`.

With the previous code, they were mapped 1-1 with `name` and `package`
but need to be inverted to match what cargo is expecting.
---
 src/metadata.rs | 34 +++++++++++++++++++++-------------
 1 file changed, 21 insertions(+), 13 deletions(-)

diff --git a/src/metadata.rs b/src/metadata.rs
index b6f39c7..aed0ce9 100644
--- a/src/metadata.rs
+++ b/src/metadata.rs
@@ -26,19 +26,27 @@ pub fn transform(
         deps: package
             .dependencies
             .into_iter()
-            .map(|v| CargoIndexCrateMetadataDependency {
-                name: v.name,
-                req: v.req,
-                features: v.features,
-                optional: v.optional,
-                default_features: v.uses_default_features,
-                target: v.target,
-                kind: v.kind,
-                registry: Some(v.registry.map_or(
-                    Cow::Borrowed("https://github.com/rust-lang/crates.io-index.git"),
-                    Cow::Owned,
-                )),
-                package: v.rename,
+            .map(|v| {
+                let (name, package) = if let Some(rename) = v.rename {
+                    (rename, Some(v.name))
+                } else {
+                    (v.name, None)
+                };
+
+                CargoIndexCrateMetadataDependency {
+                    name,
+                    req: v.req,
+                    features: v.features,
+                    optional: v.optional,
+                    default_features: v.uses_default_features,
+                    target: v.target,
+                    kind: v.kind,
+                    registry: Some(v.registry.map_or(
+                        Cow::Borrowed("https://github.com/rust-lang/crates.io-index.git"),
+                        Cow::Owned,
+                    )),
+                    package,
+                }
             })
             .collect(),
         cksum,
--
libgit2 1.7.2