Add current_page? helper for pages.

[wout]

Purpose

Implementing #1073.

Description

This adds the current_page? helper with similar functionality like the one in Rails. Although, it does not cover all Rails' cases. What it does not do:

1. handle cases with double escaped params
2. handle cases with different encoding
3. test against a full uri, including protocol and port

I'm not quite sure if they are relevant or even possible. Looking at the available data in a request, I wonder if it is even feasible to implement point 3. There is no notion of the protocol, but even then, would we even need to test the protocol?

Checklist

• - An issue already exists detailing the issue/or feature request that this PR fixes
• - All specs are formatted with crystal tool format spec src
• - Inline documentation has been added and/or updated
• - Lucky builds on docker with ./script/setup
• - All builds and specs pass on docker with ./script/test

[jwoertink]

Hey, thanks for taking a look at this! I just left a comments.

[wout]

Just pushed an updated version where host with port are tested as well if the given value is a full uri. For example:

# Visiting https://example.com/action
view.current_page?("https://example.com/action")
# # => true
# Visiting https://example.io/action
view.current_page?("https://example.com/action")
# # => false

But:

# Visiting https://example.com/action
view.current_page?("http://example.com/action")
# # => true

Might be confusing.

UPDATE

As discussed in #1073, we'll leave out the schema since https is a requirement these days.

[paulcsmith]

Really wonderful stuff. Just a couple specs for the RouteHelper version. Overall looks fantastic. And thanks for adding docs

[wout]

I assumed this was good to go, but just thought of something. The query params probably need to be unescaped before testing against the given value.

[wout]

Ok, this is the last bit I think. Now uri encoded query params are properly decoded before testing.

[paulcsmith]

Looks perfect! Nice catches and great specs