将瞬态git依赖性修补到特定的rev

Question

我依靠板条箱a和b，其中我修补了b to Ref foo fooo ：

# Cargo.toml of my crate
[dependencies]
a = "1.0.0"
b = "1.0.0"

[patch.crates-io]
b = { git = "https://github.com/user/example", rev = "foo" }

a还取决于b作为git依赖性，但没有特定的ref：

# Cargo.toml of a
[dependencies]
b = { git = "https://github.com/user/example" }

我想强制a像我一样使用相同的ref b，我认为我可以这样做：

# The ideal Cargo.toml of my crate
[dependencies]
a = "1.0.0"
b = "1.0.0"

# patch local dependency
[patch.crates-io]
b = { git = "https://github.com/user/example", rev = "foo" }

# patch transient dependency
[patch.'https://github.com/user/example']
b = { git = "https://github.com/user/example", rev = "foo" }

这是不起作用的修补仍然指向同一源，只是在不同的rev中：

error: failed to resolve patches for `https://github.com/user/example`

Caused by:
  patch for `b` in `https://github.com/user/example` points to the same source, but patches must point to different sources
[Finished running. Exit status: 101]

---

到目前为止，我的解决方法是叉b和这样的

# Cargo.toml of my crate using a work around
[dependencies]
a = "1.0.0"
b = "1.0.0"

[patch.crates-io]
b = { git = "https://github.com/me/example", rev = "foo" } # Using my fork

[patch.'https://github.com/user/example']
b = { git = "https://github.com/me/example", rev = "foo" } # Using my fork

修补。有更好的方法吗？

---

我尝试了此hack 它只是忽略了Rev。整个GitHub问题使我的尝试似乎不受支持，但很难说，因为它不是完全相同的功能。

Answer 1

per 此github问题，当前不支持此功能专门通过URL，而不是修订。有些URL被视为相同，例如 .git结束总是被剥离，但货物仍只是在比较URL，而没有其他。
但是，我们可以使用此“功能”来提高我们的优势：在URL的末尾添加？ref = foo将使它看起来像是一个新来源：

# Fixed Cargo.toml
[dependencies]
a = "1.0.0"
b = "1.0.0"

# patch local dependency
[patch.crates-io]
b = { git = "https://github.com/user/example?rev=foo" }

# patch transient dependency
[patch.'https://github.com/user/example']
b = { git = "https://github.com/user/example?rev=foo" }

---

请小心使用两个补丁，否则您将创建一个损坏cargo.lock，其中有两个定义b：

# Corrupt Cargo.toml
[dependencies]
a = "1.0.0"
b = "1.0.0"

# patch local dependency
[patch.crates-io]
b = { git = "https://github.com/user/example", rev = "foo" } # mistake!

# patch transient dependency
[patch.'https://github.com/user/example']
b = { git = "https://github.com/user/example?rev=foo" }

---

虽然我没有测试，但此方法也应原则上通过附加/tree/＆​​lt; branch＆gt;将分支上的补丁处理。