Fix errors due to "unused code" when features are disabled

[palant]

Description

Unfortunately, my previous changes caused some compile errors when compiling with --no-default-features. That’s mostly due to unused code, one error is because of a variable being unnecessarily mutable.

Related Issue

#340, #342

How Has This Been Tested?

Tests pass.

[semanticdiff-com]

Review changes with SemanticDiff.

Analyzed 2 of 2 files.

Overall, the semantic diff is 10% smaller than the GitHub diff.

	Filename	Status
✔️	src/handler.rs	11.45% smaller
✔️	src/lib.rs	Analyzed

[palant]

Because for stable compiles just fine.

As I said, this isn’t about compiling but about clippy. Using latest stable (1.77.2) I get when running cargo clippy --no-default-features:

error: used `unwrap_or()` on `None` value
   --> src/handler.rs:296:32
    |
296 |                       let resp = resp.unwrap_or(
    |  ________________________________^
297 | |                         // Otherwise return an error response
298 | |                         error_page::error_response(
299 | |                             req.uri(),
...   |
304 | |                         )?,
305 | |                     );
    | |_____________________^
    |
help: remove the `None` and `unwrap_or()`
   --> src/handler.rs:283:32
    |
283 |                     let resp = None;
    |                                ^^^^
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_literal_unwrap
note: the lint level is defined here
   --> src/lib.rs:99:9
    |
99  | #![deny(warnings)]
    |         ^^^^^^^^
    = note: `#[deny(clippy::unnecessary_literal_unwrap)]` implied by `#[deny(warnings)]`

[palant]

Whatever, I’ve rearranged this code so that we don’t have any warnings here. The optimizer can figure it out.

[joseluisq]

Thanks!