proxyplease does not appear to honor system bypass list

[vbisbest]

Testing on OSX. Sample:

	a, _ := url.Parse("http://localhost/")
	b, _ := url.Parse("https://www.google.com")

	dialContext2 := proxyplease.NewDialContext(proxyplease.Proxy{TargetURL: a})
	dialContext3 := proxyplease.NewDialContext(proxyplease.Proxy{TargetURL: b})

Output

2021/05/05 11:57:39 proxyplease.proxy> No proxy provided. Attempting to infer from system.
2021/05/05 11:57:39 proxyplease.proxy> Inferred proxy from system: http://127.0.0.1:8080
2021/05/05 11:57:40 proxyplease.proxy> No proxy provided. Attempting to infer from system.
2021/05/05 11:57:40 proxyplease.proxy> Inferred proxy from system: http://127.0.0.1:8080

Proxy settings:

Expected:
the dialContext for localhost should have been "direct"

[vbisbest]

It appears this was added to go-get-proxy in 2018:
rapid7/go-get-proxied#4

[webbrain-one]

Thanks for reporting this!

I've opened a pull request to fix the issue: #8

This update improves the proxy inference logic to properly honor the system's bypass list on macOS. With this change, requests to addresses in the bypass list (like localhost) should now be dialed directly as expected.

Thanks again for the detailed report!