Improve error message when attempting to change features when replacing a dependency (may apply to [patch] too)

[debris]

My project's Cargo.toml file

[package]
name = "sample"
version = "0.1.1"

[dependencies]
regex = "0.2.1"

[target.'cfg(target_os="android")'.dependencies]
jni = "0.3.1"

[replace]
"error-chain:0.5.0" = { default-features = false }

[lib]
name = "sample"
crate-type = ["staticlib", "cdylib"]

When I try to compile it, I get the following warnings:

warning: dependency (error-chain) specified without providing a local path, Git repository, or version to use. This will be considered an error in future versions

So, as suggested, I added version field to my replace.

[replace]
"error-chain:0.5.0" = { version = "0.5", default-features = false }

Now, I get an error

error: failed to parse manifest at `/Users/marek/projects/sample/cargo/Cargo.toml`

Caused by:
  replacements cannot specify a version requirement, but found one for `https://github.com/rust-lang/crates.io-index#error-chain:0.5.0`

---

So, either the first warning that I got was misleading, cause it suggested to use version property (via "or version to use"), or replacing version is broken

[alexcrichton]

Ah yes the intention of [replace] is to switch sources of a crate, not for overriding turning off default features. In that sense I believe what you're trying to do here is unsupported.

In any case though the error message definitely could be better!

[stale]

As there hasn't been any activity here in over 6 months I've marked this as stale and if no further activity happens for 7 days I will close it.

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[stale]

As I didn't see any updates in 30 days I'm going to close this. Please see the previous comment for more information!