[android] Replace URL tests that use hardcoded /tmp

[drodriguez]

In Android /tmp doesn't exist, and the temporary directory is normally
/data/local/tmp. It is not a symlink. The tests were mostly working, but
because resolvingSymlinksInPath returns a trailing slash if the
directory actually exists, in Android it was returning without the final
trailing slash in some of the cases.

The changes split the large test into smaller pieces that test one of
the behaviours of resolvingSymlinksInPath, and tries not to use the
temporarl directory by itself or suppose anything about it.

There are, however, a couple of tests that check behaviours that are
only applicable to Darwin, so those tests are only performed in Darwin
platforms.

[drodriguez]

Replaced the test implementation for smaller tests testing each of the parts of resolvingSymlinksInPath. I’m building macOS still, but the test pass in Linux and Android.

From my understanding, even in Windows, the URL path separator is still /, so I think the tests should work unchanged in Windows, but maybe the symlink test has to be disabled.

[drodriguez]

Small fix for macOS (a problem using temporary directory with unexisting paths not removing the /private part). Should be ready to review and tests.

[spevans]

@swift-ci test

[drodriguez]

I’m puzzled. From reading https://ci.swift.org/view/Pull%20Request/job/swift-corelibs-foundation-PR-Linux/2672/console (which seems to be the tests for this PR), it seems to have tested the previous version (c49f9fa) instead of the last version (f3b0874).

[spevans]

@swift-ci test

[drodriguez]

@swift-ci please test

[drodriguez]

Has anyone any more feedback about these changes? Otherwise it would be great to merge. Thanks.

[drodriguez]

Ready for review. Rebased with master and removed the conflicts with the recent changes for Windows.

@swift-ci please test

[drodriguez]

Rebased on top of a more current master and check it still works on Linux and Android.

@spevans, @millenomi, @compnerd: Does someone has something to say in favor or against this PR? I would love to get it merged to improve the Android support.

@swift-ci please test Linux platform

[drodriguez]

@swift-ci please test Linux platform

[drodriguez]

@swift-ci please test

[drodriguez]

Rebased and removed the couple of unwrapped that were in the diff. Ready for reviewing. This removes the last two failures in Android that are not caused by external libraries. Yay!

[finagolfin]

Can we finally get this in? I tried it when compiling master natively on Android and it gets all the tests working, along with this small tweak:

diff --git a/TestFoundation/TestURL.swift b/TestFoundation/TestURL.swift
index 21f9ca88..e6239bde 100644
--- a/TestFoundation/TestURL.swift
+++ b/TestFoundation/TestURL.swift
@@ -324,7 +324,7 @@ class TestURL : XCTestCase {
             }
         }
 
-        #if os(Android)
+        #if os(Linux)
         FileManager.default.changeCurrentDirectoryPath("/data/local/tmp")
         #endif
 

I know everyone is on winter break now, but would be good to finally get this in next month.

[finagolfin]

This pull needs to be rebased. It fixes the last remaining failing test when compiling and running TestFoundation natively on an Android host.

[drodriguez]

I was waiting for some reviewer accepting the changes (/cc @millenomi, @spevans, @compnerd). I might try to rebase during the weekend, but I cannot longer work as much as before. You are free to copy this changes, rebase them, and open another if you want to take over.

[finagolfin]

Did what you suggested, this is in now, can be closed.