Add impl Serialize and Deserialize for Option<Url>

[mhristache]

This commit is adding impl Serialize and Deserialize for Option
which is intended to be used with serde serliaze_with and
deserialize_with for derived ser/deser when an url field is optional.

This commit is also adding some tests for derived Serialize and
Deserialize via serde serialize_with and deserialize_with, as
custom_derive is stable since rust 1.15.

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This change is 

[SimonSapin]

Looks good! A couple changes…

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Reviewed 3 of 3 files at r1.
Review status: all files reviewed at latest revision, 3 unresolved discussions.

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.gitignore, line 4 at r1 (raw file):

Cargo.lock
/.cargo/config
.idea

What’s this? If it’s a file you have locally unrelated to anything in the repo, please use .git/info/exclude instead.

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url_serde/src/lib.rs, line 102 at r1 (raw file):

/// Serializes this Option<URL> into a `serde` stream.
impl<'a> Serialize for Ser<'a, Option<Url>> {

I think this can be made generic, please do so:

impl<'a, T> Serialize for Ser<'a, Option<T>> where Ser<'a, T>: Serialize

It can help if/when we add serde support for more url types, like Host.

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url_serde/src/lib.rs, line 154 at r1 (raw file):

/// Deserializes this Option<URL> from a `serde` stream.
impl Deserialize for De<Option<Url>> {

Same as above.

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Comments from Reviewable

[mhristache]

.gitignore, line 4 at r1 (raw file):

Previously, SimonSapin (Simon Sapin) wrote…

What’s this? If it’s a file you have locally unrelated to anything in the repo, please use .git/info/exclude instead.

When defining a project in Intellij Idea IDE it creates a .idea folder where it stores all the settings. I thought it's useful to ignore it as Idea IDE is becoming more and more popular for Rust development.

That said, I don't mind taking it away.

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Comments from Reviewable

[SimonSapin]

Review status: all files reviewed at latest revision, 3 unresolved discussions.

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.gitignore, line 4 at r1 (raw file):

Previously, maximih (Maximilian Hristache) wrote…

When defining a project in Intellij Idea IDE it creates a .idea folder where it stores all the settings. I thought it's useful to ignore it as Idea IDE is becoming more and more popular for Rust development.

That said, I don't mind taking it away.

There’s an unbounded number of IDEs in the world. I think Intellij users should rather use a global (to them) gitignore file:

https://help.github.com/articles/ignoring-files/#create-a-global-gitignore

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Comments from Reviewable

[mhristache]

url_serde/src/lib.rs, line 102 at r1 (raw file):

Previously, SimonSapin (Simon Sapin) wrote…

I think this can be made generic, please do so:

impl<'a, T> Serialize for Ser<'a, Option<T>> where Ser<'a, T>: Serialize

It can help if/when we add serde support for more url types, like Host.

I am hitting E0275 (error[E0275]: overflow evaluating the requirement _: std::marker::Sized
) when trying to use the signature above. Any ideas how to avoid it?

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Comments from Reviewable

[SimonSapin]

r+ with the .gitignore change removed.

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Review status: all files reviewed at latest revision, 2 unresolved discussions.

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url_serde/src/lib.rs, line 102 at r1 (raw file):

Previously, maximih (Maximilian Hristache) wrote…

I am hitting E0275 (error[E0275]: overflow evaluating the requirement _: std::marker::Sized
) when trying to use the signature above. Any ideas how to avoid it?

This might be a rustc bug. I’ve filed rust-lang/rust#39959. In the meantime, leave you impls as-is, we can make them generic later if it’s a bug an when the bug is fixed.

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Comments from Reviewable

[mhristache]

@SimonSapin .gitignore change was removed

[SimonSapin]

@bors-servo r+

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Reviewed 1 of 1 files at r2.
Review status: all files reviewed at latest revision, 2 unresolved discussions.

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Comments from Reviewable

[bors-servo]

📌 Commit 599b97d has been approved by SimonSapin

[mhristache]

@SimonSapin thanks for your time! Can you also push url_serde 0.1.2 to crates.io? Thanks

[SimonSapin]

Normally a bot should run CI and merge automatically. But that seems broken at the moment, and I don’t know why. https://travis-ci.org/servo/rust-url/builds/203163348 is green, I merged manually.

0.1.2 is now on crates.io